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I am looking to convert a std 1944 M1 Garand barrel to mount a M1D scope base. I live in the Dallas area and Im looking for info of any known milling service to cut a std barrel to M1D barrel specs?
I have had the scope base for years and have a M84 scope and a 1944 SA receiver. All I need is a std barrel cut to allow fitting the scope base.
Any suggestions?
Turned on a lathe, not cut on a mill... The rear of the barrel will need to be turned off at the shoulder just enough to fit the scope mount block/barrel to the receiver. The gunsmith will need the barrel, receiver and scope mounting block. Well, the whole thing...to be sure it's right. Then he needs to allow for the crush factor of the barrel torque to achieve TDC with the sights and all this requires an experienced gunsmith that has done this sort of thing before. Gunsmith not milling service, sounds like you're looking for a machine shop. They aren't the right guys to do it.Quote:
Originally Posted by 1903Collector
I don't believe most of the commercial M1D barrel blocks are well regarded. You might be money ahead buying a Criterion M1D barrel rather than getting a block and paying someone competent enough to install it properly. Especially if the stock GI barrel is decent enough to sell to offset some of your cost.
Agreed. Unfortunately, the .30-06 version is out of stock with a waiting list.
https://criterionbarrels.com/product...v=0b3b97fa6688
Hi again Jim, well most issues above were just a matter of semantics, but I get your point to the difference between a machine shop and a gunsmith. I just used overly generic terms, and mistakenly used "milling" instead of "turning". I am well aware the type of machining operation required is by lathe and I am assuming the base is press fit to the barrel. I was in fact asking for suggestions of who had the skills and knowledge to do the work...I understand your point of referring to them as a gunsmith, but that was my intent. It was late (for me these days) and I was getting lazy and sloppy in my typing and thinking...seems to be a trend for me lately.
So, yes, I am looking for a gunsmith experienced in turning a std M1 barrel into a M1D barrel. I was hoping someone on this site can steer me in the right direction.
For the record, I am a retired mech-design engineer and know enough of my way around a lathe to be dangerous.
A quick thought...do we know whether the scope base is pressed on the barrel before or after the barrel is fitted to the receiver?
Note: Ive never barreled a M1 Garand, but from what I recall of reading up on the method necessary to align the barrel and receiver correctly, it is a pain in the *** as there are no alignment scribe marks as far as I know. I begin to wonder if I really want to do this!
---------- Post added at 10:30 PM ---------- Previous post was at 10:24 PM ----------
Many thanks, I thought I had seen something like this some time ago in Firearms News. If I had $500 and if they had the .30-06 chambered version Id be tempted, but I already have a barrel to turn and a base...mount...whatever it is actually called. Also, I wanted to use a 1944 SA barrel for this project.
I noted they qualified the add with "mount modified by Criterion to securely tighten to the base mount and not loosen during fire. May still require leveling/truing by a qualified gunsmith." This last part means I may still need to find a gunsmith who knows how to do this!
---------- Post added at 10:35 PM ---------- Previous post was at 10:30 PM ----------
Good point. Ive had the mount for years and it came from a huge warehouse of surplus USGI parts located in Europe...Denmark if I recall correctly. It may still be a commercial mount, but Im hoping it is authentic USGI. Is there any way to tell?
I also wanted a 1944 SA barrel for this project. Im not partial to non-USGI barrels, but then again I do not intend to compete with it. The more replies I read, the more I think I may just drop this project...too many potential issues.
Here's a discussion in the CMP forum. https://forums.thecmp.org/forum/cmp-...lock-and-setupQuote:
Originally Posted by 1903Collector
The base is installed onto the barrel prior to installation on the receiver.
Barreling/rebarreling a Garand really isn't that hard, even without index marks.
Post pics of your mount, we might be able to tell you what you have.
will try, but Ive never been able to post pics...I am sure I am just not posting them correctly.
Thanks Jim, it was a good read. That thread and MAC702's reply helped clarify things in my mind.
After my last message to you I think I figured out the methods required. The mount HAS to be pressed to the barrel prior to installing it onto a receiver. I wish I could see a drawing for the base internal diameter and M1D barrel diameter after turning. If needed, I could probably select the interference fit that is pretty close to USGI spec. It will be a mid range press fit at a minimum. I am sure an alignment jig/fixture will be necessary to assure desired base and barrel radial alignment when pressed, but that is pretty straight forward (Ive designed many fixtures and tooling jigs in my career). I have a 3 ton press, so I am sure I could do it...I just dont have a lathe and am not sure Id trust myself with one anyway!
I could be wrong, but after reading the entire thread, it appeared a few were confusing the base with the mount. I have seen some repro mounts and I was not impressed. IF I have a repro base I am less concerned dimensionally, but proper hardness may be an issue. For clarity, I refer to the base as the machined block that is pressed to the barrel, and the mount as the stamped and formed item that holds the scope and screws/affixes onto the base. So I still need someone who can turn down the barrel, but Im not sure I need a gunsmith per se, with the possible exception as to whether any facing or trimming is needed to the base (as Criterion seems to indicate is a possibility in their add).
Ill have to re-read the barrel to receiver alignment process for the M1 Garand. I wasnt thrilled with the prospect when I first read it. What boggles my mind is why did Garand not include scribed alignment lines on both the barrel and receiver. It works fine for the 1903, M1917, and M1 Carbine...why not the Garand and probably the M14/M1A? What am I missing here?
Check your PM for email address, I'll post them for you.Quote:
Originally Posted by 1903Collector
---------- Post added at 06:05 PM ---------- Previous post was at 05:56 PM ----------
I would practically guarantee it. The block has to be like this so the sights come TDC and your crush factor is present...and it's all pinned together.Quote:
Originally Posted by 1903Collector
Too, you could have the flats out of whack and have an optic pointing off at an angle. Things to be aware of...then you're shooting "Over there" and can't get it correct.Quote:
Originally Posted by 1903Collector
I disagree that they worked fine, I've fitted enough barrels to find they were out by a smidge. Standards were lax enough to allow them to shoot passably but TDC is correct when it's correct. The M1 rifle sights aren't so hard to do once you've done a couple and then you get them perfect. Lines aren't needed. They would only lead you astray thinking you were correct when you weren't.Quote:
Originally Posted by 1903Collector
Agreed. I'm no gunsmith, just an armorer level knowledge, but I've done lots of Garand barrels, including at the CMP's Garand building class. A couple of alignment rods for the rear sight flat and front sight flat (temp fit the gas cylinder) make it an easy task. Have the correct barrel or action vise, and correct action or barrel wrench.Quote:
Originally Posted by browningautorifle
I had to make a barrel vise and an action vise that I could come on to and I use an angle meter on the front sight flat and rear sight flat. That works for both M1 and M14. This scope mounting block will have been put on with a jig for locating and then machine drilled and pinned. Not done by eye or guess.Quote:
Originally Posted by MAC702
Is the fit between the base and barrel perhaps more of a slip fit, or a very light interference fit then? Drilling and pinning and using a fixture as I think you mean would indicate that the base would be rotated slightly, as needed, after sliding or pressing it on the barrel to achieve perfect alignment before pinning (I am assuming the pin hole is then match drilled after final orientation is set.)\
I was unaware that these bases are pinned. I need to do more homework, but also get my hands on the drawings.
From an design engineer and manufacturing point of view, no, the scribed lines should be absolutely correct, being scribed within a calibrated jig (or so would have been my spec if I had been the design engineer). I have also barreled nearly 100 M1 Carbines, over 200 '03s and 1 (one) M1917 and the results were always dead on.
HOWEVER, to my surprise I am currently working on an M1 Carbine and the scribe lines DO NOT line up! This is a first for me. The early WIN barrel is NOS from James River and the receiver is WIN is an early SN, but in not so good condition. I suspect the barrel, but there is something else going on with this barreled receiver. It may be an optical illusion, but the centerline of the barrel does not seem to align perfectly with the center of the receiver when looking down the length from the back of the receiver. It is as if the center of the threads of the barrel is not concentric with the bore, or the thread of the receiver is not aligned with the center of the receiver. Ive never seen such a thing before. Yet, when fully assembled, the carbine seems to function properly with rounds feeding and ejecting from the barrel without any problem. Even though the receiver is in poor cosmetic condition, I begin to suspect that the barrel is the problem...and I paid A LOT for that barrel!
Very tight and drilled to pin. Then the whole thing is done with machinery set up for the job. I'm sure you'll eventually curry out a picture of an original barrel in the loose.Quote:
Originally Posted by 1903Collector
Asking about the indexing line for carbines, ask Charlie over on the carbine forum. Those guys have had lots of spares go past them and can tell you more perhaps. I just know I disregard the lines as a guarantee.
This is my understanding as well. Barrel and action vises I got. I recall the instructions I read a while back about the angle meter (this version instructed the use of a level on the sight flat after the receiver was verified level). I like the idea of an angle meter much better, BUT I dont have one...unless there I can use an ap on my cell phone????
I don't bother making anything level. I put a straight rod through the rear sight holes, and a straight rod on the gas cylinder flat. Torque until they are dead parallel.
An angle meter is a cheap addition to your tools, can be found anywhere like a "Princess Auto" type store. I've never used the levels, an angle meter can tell you how many degrees you're out of TDC and you can match front and back that way.Quote:
Originally Posted by 1903Collector
Yep, I realized that once I saw your comment. That eliminates the need to 'level' the receiver and is surely far more accurate!
Before I spend monies not in my pathetic senior citizen budget, I still hope I can just load an angle meter ap to my phone. HOWEVER, my shop is FULL of tools acquired over the years for reasons such as this and I would not mind adding yet another one! :-) A MAN CAN NEVER HAVE ENOUGH TOOLS, FIREARMS, GUITARS, AND AIRPLANES (OK, so I cant afford vintage military airplanes, but a man can dream, even at my age!)
---------- Post added at 10:45 AM ---------- Previous post was at 10:43 AM ----------
You have a far better eye than I have, but I understand the logic and validity of that method. Cleaver! It would more than do in a pinch if other tools are not available!
I couldn't say about that one, the angle meter was about $15CDN... I've used it many, many times.Quote:
Originally Posted by 1903Collector
I did the exercise in another thread, but since the topic is at hand, I'll do it again. The spec for alignment is +/- 20 minutes. With the front sight height spec .728-.005 and sight radius is 29.5, this translates to a max +/- 0.0042 of the front sight - which even the best eyeball can't see, but which gives not more than .522 MOA downrange. This means that, with a set of 24 inch alignment rods, your eyeball needs to detect a ~.070 difference at the rod tips to be within spec. or double that for 48 inch rods. It is challenging to get a longer front rod to sit flat on the front sight base, so there is likely a source of considerable slop there depending on how patient you are. I used to use the rod method with 2ft rods until I was gifted a badger jig set. It took some time to get that front rod balanced perfectly, the jig takes hardly any setup time at all. So I went back and checked my work on half a dozen re-barreling jobs I had done, as well as ~half dozen rifles with original barrels, with the jig and a machinist level with 90 second graduations. I found that with rods I averaged about 12MOA with eyeballs - best was 8 worst was 18. Of the originals, the best was 5 and worst was 11 MOA. The originals were almost always over target (past true) and I was always under target.Quote:
Originally Posted by MAC702
With the jig and a good level, it is pretty easy to get <1MOA every time. While it will make some sleep better at night, given my first sentence if your eyeball can detect .070, you will be within half a click of true, or 1 click if you have the NM knob installed.
EDIT: When using rods - I found it helps immensely to put a sheet of plain white poster board behind your setup.
Well...OK, I think I can afford that! :-) Hope I dont have to order from Canada...Trump will be ****ed at me! :-P
What can he do, cut your hair and make you join the Army? Let us know how this goes...worst case I can box my angle meter up and mail it. Gift...doubt I'll do any more of them any way. One old guy to another...Quote:
Originally Posted by 1903Collector
Hey, Id go USAF as long as they let me fly again...and I just got my hair cut yesterday...military high and tight (like Harrison Ford in Enders Game...I even look a little like him...Im in better physical shape but absolutely no talent nor camera presence). My Dad di, could have been a movie star! My Dad and Grandfather were both USAF pilot war vets and retired as Lt. Col Ret., but I didnt make a career of it like them.
Seriously though, I VERY much appreciate your offer, but I will buy one here in Texas. :-)
I was army, Infantry and am glad not to be on cold miserable days...snowy or freezing. I couldn't take it any more, wouldn't be able to stand it. Too broke down from doing it when I could...Quote:
Originally Posted by 1903Collector
The unofficial motto for the Engineer's school at Chilliwack was "if it ain't rainin', we ain't trainin'!" Fortunately our training was never curtailed due to lack of rain.Quote:
Originally Posted by browningautorifle
No lack in the Lindsay Valley...or OPSEE training area. Or the heat of summer.Quote:
Originally Posted by Sapper740
I know someone with a spare 3006 criterion m1d barrel. Pm sent
I am going with Jim's recommendation of a digital angle meter. I had already done the math and rejected the rod alignment process as having too many variables to control and then its still depends upon a human eyeball judgement, and human error is a factor of Murphy's Law that seems to always seek me out.
The specs and "rod" process variables you provided are greatly appreciated. Being a retired mech design engineer I live an breath math and specs! :-)
Ive still got more than a few 1903 projects to complete and then still need to fit the M1D block to my selected barrel before i am faced with barreling my receiver with that barrel, but Ive got two other M1 Garand receivers with "matching" barrels and I think Ill practice barreling M1 receivers with them first with an angle meter.
I still cant fathom why Garand chose not to employ alignment scribe lines. Ive discussed this briefly with Jim in the past and I have math and mechanical design and manufacturing process reasons why I completely disagree with Jim's position on the inaccuracy of alignment scribe lines on the '03 and M1 Carbine barrels and receivers. I think many people misunderstand the actual mechanics the so-called "crush" factor when barrel torque specs are met when properly aligned to a receiver. I also know that if the rear sight mount body is not perfectly installed and aligned with the barrel scribe mark then it may seem that aligning the '03 barrel using the RSMB seem line to align to the receiver scribe line is not always correct.
HOWEVER, my entire experience is limited to Military long arms and I have none with modern commercial rifles, especially those with barrels that are completely symmetrical and have no front sight features that require alignment to the receiver. In fact, I am assuming that there are even rifles with such barrels...such is my limited experience! Vintage surplus military rifles, well over 500 have gone thru my shop of nearly all kinds in the past 29 years...but modern commercial rifles, NONE! Im thinking there may be a difference there.
---------- Post added at 11:29 PM ---------- Previous post was at 11:25 PM ----------
Thanks, but Im USGI parts only! I value authenticity more than accuracy and remaining barrel life. Putting these old soldiers back in uniform is my thing even if I am building an M1D with a receiver that may never have been an M1D previously. Having said that, I am no certain I can pull this project off, but its always fun trying! :-)
I might suggest you pay close attention to the tolerence of whatever tool you have or plan to get. Most of the cheap digital levels you find don't even advertise their tolerance, and when they do, it is likely the range of the sensor, NOT the whole system. Most of the budget tools (like Klein, for example) advertise +/- 0.1 degree within a degree of 0 or 90, and 0.2 in between. 20 minutes is .33 degrees. I saw a cheap one on amazon claiming 0.029 deg, so you might think you are ok? Not so fast, the bodies are all plastic, with a groove down the length for pipes. I doubt there is any uniformity along their small length even close to the reported tolerance of the sensor. Great for hanging pictures, setting a line laying bricks, etc., but I wouldn't set a barrel with one. I didn't look too hard, but I failed to find a budget friendly tool (< $100) that looked adequate in overall build. A Mitotoyu digital protractor in the tolerance range we are talking about will set you back $275 minimum - over double the cost of a good machinists' spirit level with similar tolerence. Refurbished ones can be had even cheaper on eBay.Quote:
Originally Posted by 1903Collector
Another thought, how do you plan on taking the reading? Across the top of the ears are not a very good reference point, so you will need a square block, or the badger ord. jig, to sit between the ears. I think the jig is ~$90 if you can find it. You can likely get by with a 1-2-3 block. All this in mind, I think the logical conclusion is the only acceptable "budget" method of properly timing an M1 barrel is to get a set of drill rods (assuming you don't have any tools yet).
Just saying.
I suppose I'll chime in on this one too. I have no preference for or against the design of witness marks, or lack thereof. But as to why they were not used on the Garand...I think perhaps it had to do with the controlling of stacking tolerances between the concerned reference points and the impacts on production effeciency. As evidence, I reference a scathing review of Springfield Armory practices during 1903 production in Fred Colvin's autobiography "60 Years of Men and Machines". Colvin was asked by the secretary of war ~1916 to review manufacturing processes at Springfield Armory. His negative report, basically calling out the whole operation as bass backwards and antiquated, caused quite a scandal. Colvin thought his review was for the Secretary's eyes only, but some biased Generals got their hands on it first.Quote:
Originally Posted by 1903Collector
So, I think the real reason for no witness marks on the garand can be as simple as the elimination of an unnecessary production step. We often overlook the fact that there were far more considerations in design and practice than just the rifle itself.
That's right.Quote:
Originally Posted by ssgross
SSGross is correct that there are additional process steps, and even a special fixture for cutting the "draw line" on the receiver and barrel on the 1903 Springfield. The "draw lines', as named in the process route follower, are created in a separate manufacturing process step and has its own precision fixture. As a result, the locations of these lines are, for lack of a better term, dead nuts accurate with the possible exception of the human factor of securing the work piece in the respective fixture. This and the following can be verified relevant sections in the works provided by Brophy and by Herbert (both are ponderous to read, but include both engineering drawings and sketches of jigs and fixtures as well as the original process route follower work instructions.
Upon review, I was amazed at how many individual process steps were required and at the large number of custom precision jigs and fixtures were necessary. Of course, this was long before the days of CNC machining and 5 axis machines. I can understand why Fred Colvin's review of the manufacturing processes at Springfield Armory resulted in a negative report, but I challenge that he actually stated that the whole operation was "bass backwards and antiquated". However, it is indeed complicated and the process routing is quite astounding.
This may indeed explain the decision not to utilize alignment "draw lines" on the M1 Garand, but I have trouble accepting that. In any case, it would have been possible to include "draw lines" and they would have been very effective. I can only conclude tht either it was an unintentional omission, or related to reduce and simplify process steps, operations and fixtures, or that there was some other reason yet to be learned.
Actually, part design, manufacturing processes, jigs and fixtures and inspection fixtures and methodology is my professional expertise (2 years in the oil industry BOP and tools and fixture design, 2 years EVA equipment design for NASA STS 11 & 13 missions at JSC, 13 years bio-medical automatic blood blood analyzer design, 4 years cell phone, and finally 4 years aerospace). After careful review and many cups of coffee I can point out that Brophy and Herbert have some part, jig and fixture dwgs as well as a process route follower for every step in the manufacture if the '03 receiver and barrel that helps to address, at least in part, this topic. However, I was disappointed that there were still a few details not provided. I spent the last week pouring over these to capture the design intent, manufacturing process and the implications of assembly methodology. The possible, if not potential errors inherit in the manufacture and process steps as well as the possible resulting variation due to these possible human factor errors.
What I write below is not absolute, and it desperately needs peer review to identify corrections or improve the clarity of the text. The following statements accepts as being read that the cutting tools are not worn, the cuts are all made to spec, and the precision jigs and fixtures are verified to the dimensional and assemble specs for them. This is not an unreasonable starting point since the tools are under strict maintenance control and the jigs and fixtures are crafted and rigorously inspected to meet all specs with no deviation at all from the dimensions (i.e., jigs and fixtures are made exactly to nominal with no tolerance allowed from the dimensional and geometric spec). This is as true today as it was then in the manufacturing industry, in fact, it is essential. Variations in manufactured part dimensions and geometry is nearly always due to:
1) improper fixturing or movement of the work piece (related to errors in seating and affixing the work piece to the jog or fixture) at the particular process step;
2) machine operator error, and
3) flaws in the work stock
However, the issue of barrel and receiver alignment is not tolerance stack up in the sense suggested. The specific dimensioning of the interfacing parts offer the absolute minimum in tolerance stack up, and after reviewing the tolerances of the mating features of the receiver and barrel the worst case is extremely tight (this worst case scenario is statistically unlikely, since actual max stack up in a typical population of parts is distributed within +/- 3 sigma) and within seconds of an angle in the position of the start of thread of both the receiver and barrel. The biggest variation (within spec) is due to the dimensional clearances and tolerances of the internal and external threads, but this variation only results in differences in the torque necessary to align the "draw lines" of the barrel and receiver. Due to the precise orientation and location of the start of the first threads of both parts, the final alignment and torque is solely dependent upon alignment to the "draw lines" when the shoulders of the barrel and receiver are in contact. Headspace adjustment or results are related to solely to these features.
Note: when the shoulders of the barrel and receiver are in initial contact the draw lines do not align. When they are aligned by applying torque the shoulders do not "crush" or deform. The mechanics in action is the increased binding of the mating sheer surfaces of the threads (which have small dimensional variation thread to thread and what is happening is the taking up the small slack due to nominal internal and external thread clearance as well as closing the equally small tolerance stack up of the location of the mating sheer areas of the threads. Wear of the mating thread sheer surfaces can at times allow over rotation of the barrel to achieve the required torque. The addition of shims serves to take up the additional slack and does not result in any change to the headspace as long as the draw lines are aligned. Note: alignment of the draw lines not only sets the headspace, but also sets the alignment of the position of the barrel features relative to the bolt lugs. (We all know that a barrel that is rotated too little or too much often prevents the bolt from seating and the bolt wont come even close to closing.)
Help me understand what I'm missing, please. I can see how a modern digital (assuming the resolution was accurate and calibrated) angle meter might be the best way, but how would lining up two marks at a barrel/receiver interface (less than an inch from the axis) be more accurate for the eye than making two 24" rods parallel?
I mean, I've used the marks on M1903 Springfields and M1 Carbines, but when I did a Garand with the rods, I thought it was easier to be more confident that I got it right. Without a vernier scale, it's not so easy to see when two marks are perfect, and the shorter the radius from the bore axis, the less the resolution/accuracy.
But, again, I'm no gunsmith. Just armorer level stuff that's included my share of barrels, but all have been new barrels that needed to be finish reamed after installation. Maybe that makes a difference?
LOL. That was my summary of the point after reading quotes from Gen. Crozier's response after intercepting the report. There is a referenced account of all this in Canfield's new model 1917 book. I haven't gone digging for the General's full paper trail yet. Canfield should have them in his bibliography. One can read Colvin's full account. He published it to counter the smearing of his name.Quote:
Originally Posted by 1903Collector
https://archive.org/details/cu31924012809897
And covers the topic again in his autobiography
https://archive.org/details/60yearsw...ge/n5/mode/2up
I do have a Remington 1903a3 with its original barrel and inaccurate drawing marks - or inaccurate front sight milling. How to tell which is at fault? The receiver mark? the barrel mark, front sight milling, receiver reference point, or perhaps all of these? It doesn't matter how dead nuts accurate one of the marks are if there was a problem in any of the other 3 surfaces. No drawing marks by design eliminates 2 degrees of freedom during the manufacture. I think this had to be intentional in the final design and manufacturing set up.
I think I posted a picture of this rifle and its problem before our great forum blackout event. I think the marks were off by (under) 2 or 3 widths. At first I thought the front sight blade, or the base holding it, was bent. Swapped for a NOS set off a barrel still in the wrap and discovered it wasn't the sight or base. I fixed the issue by lightly peening the barrel shoulder and ignoring the drawing marks when re-installing. Rifle shoots great.
I gave a calculation on max tolerance at the tips of the rods above. Here is the other half with drawing marks for comparison.Quote:
Originally Posted by MAC702
The drawing marks on a 1903 are ~10-20 thou in width (seem to be less pronounced on a 1903 and more pronounced on an 03a3), so you might say the assumed accuracy lining them up with a really good eyeball is a fourth of that? The barrel shoulder I think the receiver ring is about 1.300 on a 1903, and pretty even with the rear sight sleeve's edge (the paper weight receiver I'm measuring as I type was highly polished, so I might be off a few thous). So, if you can get the marks to line up within 1/4 of the drawing mark, you are within 13.2 minutes. So what if the same mark was on the shoulder of a garand barrel which is only ~1.100 diameter? ~15.6 minutes. This is why I use a good magnifying headset whenever timing anything with drawing marks.
For these reasons, I think it is MUCH easier to get in the spec of <20 minutes with rods vs. drawing marks, manufacturing efficiencies aside.
Your point is taken regarding the precision of alignment of a feature to a line on a surface just over 1" in diameter is far less precise as alignment to features much further from the center. However, I prefer the "draw lines" (not "drawing lines") of the '03 and M1 Carbine and find aligning them to form one colinear line to be straightforward, but your are right, is my eye good enough to see angular deviation in minutes, let alone seconds...no! However, of the 300 plus total of '03 barrels Ive aligned to a receiver and 100 plus M1 Carbines over the past 20 plus years, I have yet to observe an alignment issue using the draw lines. That doesnt say it doesnt or cant happen, but a sample size of 400 plus barrels seems good sized representation of the general population that seems to indicate a compelling statistic. I should confess that the bulk of my experience is on pre-WWII '03s and not so many A3s.
As to which is is correct, the alignment of the "key" notch of the barrel (I am not sure of the correct nomenclature) with respect to the receiver into which the bolt lug must pass is the most important. According to the process route follower the front sight key slot operation was performed towards the end of the manufacture of the barrel and after the draw line has been marked. So yes, front sight alignment may have the greatest chance of error during the manufacturing process, but Ive never seen one. I have seen different front sight features across many '03 and A3 barrels, especially early '03 barrels and...I think Sedgley does it differently as well. Ive have seen where the rear sight mount body was mounted out of angular alignment to the barrel. That part hides the original draw line and uses the center "seam" of the rear sight mount body as the line to align to the receiver raw line. Ergo, if the rear sight mount body is not aligned to the barrel itself, then when barreled to the receiver using the seam line the front sight will appear to angularly misaligned. Move the barrel to align the front sight and the rear sight is off! But I am sure this is known by all involved in this thread.
All this is academic though as we are discussing the question as to why Garand did not specify draw lines. I doubt we will ever know, but it seems strange to me that he would do that to simplify the receiver and barrel manufacturing process while at the same time requiring far more elaborate jig and or fixturing to assure alignment when barreling the receiver. As to methodology, I will follow Jim's recommendation and use a digital angle meter. It seems to me that this is far more precise, or at least offers fewer variables then the rod method, but to each his own. Still, I would rather Garand had specified draw lines! :-)
---------- Post added at 09:37 PM ---------- Previous post was at 09:28 PM ----------
Yes, all new barrels are "short chambered" The '03 short chamber distance is specified in a drawing in either Brophy or Herbert (I can find the page again but Im too tired tonight and cant seem to rise up out of my easy chair).
Barrel alignment does three things, it sets the nominal headspace as designed, it aligns at least the front sight (also rear on the '03), and aligns the barrel bolt lug key to the receiver, and indirectly, the bolt so that it can close and extract.
I am surprised to hear complaints of draw line misalignments, and my mind initially leaps to the thought, "something else is amiss", but bever say never. With these rifles I sometimes feel that the more I learn, the less I know for certain!?!?
---------- Post added at 09:40 PM ---------- Previous post was at 09:37 PM ----------
Just to restate my previous comment, I found the vast number of operation steps and custom fixtures required just to make an '03 receiver and barrel to be daunting! I am glad I was not a machinist at SA in those days!
I found myself thumbing through Colvin's thorough review book last night after our discussion (not the same as his intercepted summary report to the Secretary. I still need to find that). The draw line on the barrel is indexed after threading with a simple screw on device that makes the mark as it gets tightened onto the barrel shank (operation 34 page 18). It appears the front sight spline (operation 23, but described after 34) is cut after and indexed off the barrel draw line. Looks like this is another source of possible eyeball error.Quote:
Originally Posted by 1903Collector
The draw line on the receiver is indexed off the side of the lug (operation 17 page 51). The receiver threads are then indexed from draw line later.
I'm sold that the decision - maybe not by Garand himself - was deliberate. Besides, the front sight isn't really in final alignment from the barrel timing, but from the splines on the gas cylinder - so what would be the point. Sure they are all dependent - but any misalignment barrel and gas cylinder splines can be corrected by timing the barrel, so why would you want to set the barrel timing before all this? I need to grab my Kuhnhausen manual. I'm pretty sure there is a spec and range for the gas cylinder splines. Now I think it's even more common sense. Just thinking out loud again.
I was just cleaning my m1917 last night to take to the range today and try out my new Parker hale sight I installed. While I was at it, I decided to do a full disassembly and catalog my parts to see just how much of a mutt she is. Winchester receiver with its original winchester barrel. The draw marks are misaligned by about half the width of the line. Front sight is still in its original staked position, dead center. With the original sight, she was dead zero at 100yds.Quote:
Originally Posted by 1903Collector
This is a good point. We were taught to lightly tap on the gas cylinder that will be the final one to use with that assembly, when doing the barrel job, using another gas cylinder only when you had no choice.Quote:
Originally Posted by ssgross
Colvin, not Herbert!!!! Arghhh
Many thanks for referencing the page, operation and figure numbers. It makes it so much easier to discuss these issues more fact based.
But look again at the figure (59A) and text (operation 34) on pg 18. It is a spring loaded chisel requiring the fixture to first be aligned and fastened. The barrel is not marked AS the fixture gets tightened onto the barrel shank, it is fully secured and THEN the the chisel is struck to mark the barrel (I would have thought it would be in an arbor press in the same manner as the receiver draw line is made, hmmm, maybe that is what the instruction meant???).
Having designed many tools, jigs and fixtures in the corporate world over many years I cant help but have faith that the manufacturing engineer's fixture design eliminated any play in the fixture orientation and the chisel X & Y position. A limited slip fit with L over D ratio of the chisel guide cylinder and fixture bore of more than 3 would allow nearly zero deviation. Of course, I am biased, but without the detailed fixture drawings I have to rely upon my industry experience and hopefully not misplaced faith in the manufacturing engineer. Note that the "draw line becomes the working point for future operations".
The front sight spline operation (operation 23, pg 18) starts with fixturing the barrel in place and aligning the barrel to the fixture with a knife-edge stop. This is not an eyeball operation and one assumes (there I go again) that the knife-edge stop edge profile is identical to the draw line chisel edge thus eliminating play in location stop (at least that is how I would have done it).
The receiver thread is also indexed to the draw line via a precision fixture.
So we have two precision fixtured operations on the barrel that offer little or no deviation from spec of the angular relationship of the draw line to the thread start and barrel center, and with the receiver draw line precision fixtured operation that also offers little or no deviation from spec (ASSUMING human error in seating the workpiece in the fixture is NOT introduced). Ive seen that happen. One can create a design that is idiot resistant, but there is no such thing as fool proof!
Thus endeth my rationale for challenging claims that draw line locations have inherit error...not if the barrel and receivers are made to spec and not unless the draw line was somehow obscured, eroded away, or worn off and an attempt was made to manually re-scribe one of the lines.
The same can be said about the installation and alignment of the "fixed base", also performed as a precision fixtured operation. The operation instructions does not specifically reference the knife-edge stop registration of the barrel when fixturing the barrel (fig. 226 pg. 39) nor that the same knife-edge stop is used to orient the fixed base, and it is not clear in the figure (226) but prior references and the reference of the 'side line of the fixed base replacing the barrel draw line' for all subsequent quality measurements and registration (note that one of the gage fixtures verifies the orientation of the side line of the fixed base to the extractor cut of the barrel ("extractor cut" so THAT is what it is called!!! Ah ha!). The factory barreling of the receiver is also done via a precision fixture. This leaves but one potential eyeball orientation error, and that is manual barreling of a receiver using the eye to align the side line of the fixed base or draw line of an A3 barrel to the receiver draw line. Although I feel very confident in being able to align two lines to be colinear by eye with little or no error, I concede that this is THE source of potential error in proper alignment of the barrel to the receiver!
HOWEVER, and this may be somewhat unrelated (and a new topic), as much as I work to defend the individual steps of a VERY complicated and long fabrication process of the '03 barrel and receiver, I have a problem with the process of pinning the fixed base to the barrel. The rear base spline spline hole is a match drill operation after the fixed base is installed onto the barrel! Despite the fact that Fig 237 pg. 40 shows that the hole location and drilling is done via fixture, I have observed scores of such holes located at varying angles from TDC and even on the opposite side of the sight flat! That sure makes replacing a damaged fixed base on a good barrel VERY iffy with respect to proper alignment. I can only guess that the fixed base/barrel assemble is intended to be a matched piece with the two discarded if either barrel or fixed base were damaged, or a similar fixture was used if and when a fixed base was replace on a barrel at an arsenal for rework.
I didnt fullly follow your point about the Garand, but that isnt a surprise since my questions demonstrate that I have far less familiarity with the M1 Garand. However, to address one point, the M1 barrel alignment to the receiver establishes the alignment of what I will call the extractor cut, or cuts on the chamber sleeve of the barrel. The need for that feature to be aligned is key, just as the extractor cut of the '03 barrel must be properly aligned with the receiver in order for the bolt to chamber and extract let alone even fully close. Surely its the same with the M1 Garand. I am unaware of barrel alignment to the receiver of the M1 Garand to be related to barrel timing. Perhaps I am confusing two different things, but I am familiar only with referring to the "timing" of the M1 Garand and that it had more to do with the operating slide and movement and not with the barrel alignment to the receiver at the specified torque.
I cant comment on the M1917 as I have not studied the manufacturing process. Its a Brit design, so there may be operation differences. Ive a Win, a RA and an Eddystone and all three have perfect alignment of the draw lines. You have offered another observation of misaligned draw lines, so the mystery continues. I am just too much of a mech design and manufacturing engineer to accept that this is possible when all of the design and manufacturing engineer specs are met and followed. But we all know what pride comes before!
There is usually plenty of forgiveness here - at least there should be - much more than the <20 minutes of the front sight. More off topic, but I say "should be" because I can report from experience that on brand new criterion krag barrels the extractor relief cut is quite exact - no tolerance at all. I scratched my head first one I did wondering by the bolt was sticking. Took the new barrel off and compared against originals I had and...yep. the originals are all ~10 thous. wider than the new one. Haven't had similar issues on any other make of rifle and criterion barrels.Quote:
Originally Posted by 1903Collector
correct. I should have said "AFTER".Quote:
Originally Posted by 1903Collector
There was an historic video posted and discussed some time ago of m1917 manufacturing that showed a workman installing barrels onto receivers. If I remember correctly, the receiver was held stationary while the barrel was turned by a machine. It looked like the operator manually stopped turning when the marks were in alignment. Maybe someone with better googlefu can find it.Quote:
Originally Posted by 1903Collector
Don't forget to first peen the edges of the barrel splineways, as needed! Both sides of the top one, and the lower edges of the other two.Quote:
Originally Posted by MAC702
I suppose I will finish by saying, with a smile, that we have expended exponentially more words on all the many steps needed or accomplished to ensure draw lines are accurate enough than we have on the rather simple process making sure an m1 barrel gets timed to spec. without draw lines. This should also be evidence that the garand production crew had a good handle on the topic.
two words - government employees. They come in many different varieties of enthusiasm, effort, character, ethics, etc. I'm sure this was just as true back then as it is now. Canfield's book references labor turnover reports as well. I think at the start of M1917 production Winchester was at 269% attrition per month for a workforce in the thousands, giving an average time on the job of ~10 days. Competition for skilled labor was fierce, and most didn't last for lack of skill but because of substandard or no housing, access to food, etc. Communities around the factories couldn't just switch on access to necessities for 13,000+ new employees and their families.Quote:
Originally Posted by 1903Collector
Here is my m1917 drawing marks.
Attachment 138751
The darker area of finish is a perfect "shadow" of the lower band. There is another even more perfect shadow of the upper band, complete with screw hole, just in front. Must have been during the last arsenal refurb when it was parked. My guess is bands and front sight were left on and the sandblaster operator neglected to move the bands to get underneath. The blued areas of course didn't take the park. Original finish under the front sight too. I corrected the timing of my 03a3 since it was very noticeable by eyeball and effected the zero. I have no reason to touch this m1917.
FOUND IT.
https://www.youtube.com/watch?v=39wM-lzDWE4
1:50 spline milling. given the man doesn't seem too careful in inserting the barrel to the fixture, I'd guess the threads and draw line are indexed off the spline he cuts.
Ok, I was wrong about attaching receivers. I must have been thinking of a different video of a different rifle's assembly
5:33 barrel attached to receiver, looks like it's all eyeballs.
EDIT: Just to stay on topic...m1 rifles attached to receivers and aligned starting at 1:38
https://www.youtube.com/watch?v=44GtT7yxJEw
I can't see anything...Quote:
Originally Posted by ssgross
This video?
Manufacturing the M1917 Bolt-Action Rifle - ORIGINAL FOOTAGE - YouTube
Well now, I see the video in my post and yours.Quote:
Originally Posted by browningautorifle
"https://youtu.be/39wM-lzDWE4" is the 1917 video (which you also found)
"https://youtu.be/44GtT7yxJEw" is the second video I posted showing garand production in case you can't see it either.
I still can't see it in yours though...that's happened before too. Here's the second one too...Quote:
Originally Posted by ssgross
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