a3 front sight post

up next on my list...this A3.
I'll start by saying it shoots great...but zeroing requires maxing out left windage because the front sight is obviously pointing to 11 o'clock or so.
The blade is not bent.
The witness mark on the receiver is perfectly aligned to the one on the barrel.
When zeroed, a witness mark on the original rear sight housing (yolk holder? whatever) lines up with a corresponding witness mark on the receiver bridge.
My conclusion therefore is that this barrel was made this way - and it is annoying as a left handed shooter to have the rear sight assembly pushed off-center all the way over by 1/4 inch or more.
During manufacturing, was the timing mark on the barrel applied before or after it was put on the receiver? If I unscrew the barrel 1/12 of a turn (maybe a bit less) will this create excessive headspace? Right now headspace is tight, bold barely turns on my Forrester no-go.
Attachment 113869Attachment 113868Attachment 113867Attachment 113866
It was hard to get a good picture that shows what alignment the eye sees. Third pic falsely looks like the blade might be bent only cause the camera lens was off center a bit.

I would start simply by making sure the key for the front sight band is in place.
If for some reason the key was not installed or the wrong size, fell out or was lost, the band may have just become slightly rotated.

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Originally Posted by Doco overboard

the key was not installed

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That's what it looks like. Check out the front end first.

There certainly is a key in there, me thinks
Attachment 113887
The key or keyway could be damaged, or the key too small. I'll give it soak again. I tried to get the pin started - right to left (looking from behind the rifle) - with a regular punch and lots of small taps. I didn't want to beat on it and break/bend my punch. I think I need to support the blade with a block of wood, and give it a really big fing whack with a small nail set to get it started. The pin is tapered right? and right to left is the correct exit?
I saw chuck's method of cutting it off - but will try to save it first.

Yahtzee that was easy! Got the pin started moving right to left with a 1/32 nail set and a very big hammer. I supported the sight with wood door shims to protect it. When I switched to a regular punch, it wouldn't budge. Tried hundreds of small taps - tried to let the vibrations work some more kroil around it. punch started to bend.
Hmmm. I took a small hand torch and lightly touched around the the pin for a few seconds - just a bit of warmth - I could still touch it without burning my finger. punch snapped midway up the tip...but the shortened punch then started to move the pin right out!
Muzzle against a carpet on the concrete floor, and a piece of hardwood dowel behind it. The sight collar started to move after a few blows.

Now the diagnosis...nothing wrong with the key (key came out after scrubbing with kroil and pulling with needle nose). Either the keyway was cut wrong, or the witness mark on the barrel was off, or both - this barrel was over timed quite a bit. I used a hex wrench to make sure my level was on the flat of the milled part.
Attachment 113904Attachment 113902Attachment 113903

Just to convince myself I'm not going crazy, the marks do match up. Were the barrels marked when manufactured, or when assembled? I thought since all the replacement barrels I've seen already have witness marks on them they were pre-marked.
Attachment 113905

I'd unscrew it and recreate the crush factor and tighten up again. I've come across lots of witness marks that didn't match. Lots...

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Originally Posted by browningautorifle

I'd unscrew it and recreate the crush factor and tighten up again. I've come across lots of witness marks that didn't match. Lots...

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Yep. I was very surprised by how far off this one was. Glad I got the sight collar off so I can knock the light rust off and make it last for several centuries to come.
I'll pull the barrel off, likely this weekend, re-index, check headspace is still good, and post back.

Looking forward...

Well, Jim, you may have to wait a while. I shopped earlier in the week for a 1.175" aluminum bushing for my brownells barrel vise. Thought I had one coming but no-dice, backordered. I'm gambling that the no. 5 steel bushing will work - it's in stock. Brownells says it fits Mauser 98 military barrels, which best I can find on the interweb is 1.2", same as the 03a3. Am I wrong?
Now, I've never used a steel bushing before. Can I wrap aluminum tape on the barrel to prevent damage to the finish, same as I do on the action?
For anyone else that stumbles on this now, Chuck's thread is a must read, although his equipment is a bit more than my DIY shop. For convenience...https://www.milsurps.com/showthread.php?t=26677

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Originally Posted by ssgross

Can I wrap aluminum tape on the barrel

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Don't think so. We used a Brownells resin to hold things but I don't think they have it any more. Some have used Oak blocks. I personally make my own out of 1' by 2' aluminum bar cut into four inch lengths. Drill the hole to get started through both together and drill bolt holes the other way. Then you make your blocks. There's usually enough edges to get hold of and you can't scratch.

I've already got the barrel vise, and rosin - just need the correct bushing. The brownell's vise has a 1+3/4" opening. Fleabay bushings all seem to be 1+1/2 od. Only the steel bushing no 5 was in stock - it should fit? Am I right the Mauser 98 shoulder is 1.2"? - the a3 seems 1.195, which is why I asked about a few wraps of aluminum tape, then the steel no. 5 bushing in the vise.
If it's not the right size, it will be a long wait I suppose - or make my own with wood blocks as you suggest. I'm in no hurry, and I already left my disappointment at not getting it done this weekend in an empty beer can...which I suppose I could make an aluminum shim out of for the steel bushing if it's a bit too big?

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Originally Posted by ssgross

I suppose I could make an aluminum shim

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Don't know about the shims. I don't know if they'll slip. I used solid blocks.

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Originally Posted by ssgross

Just to convince myself I'm not going crazy, the marks do match up. Were the barrels marked when manufactured, or when assembled? I thought since all the replacement barrels I've seen already have witness marks on them they were pre-marked.
Attachment 113905

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Just a thought, when you peer into the breech, does the barrel extractor cut seem to be off as much off as the front site is rotated?
I'm just going off the pictures supplied earlier in the thread, the front site band appeared to have a pretty good lean to it.

One time I had a replacement barrel either for a M17 or P14 that had the index mark off just a touch more than the index mark was wide. Luckily the manufacturer had cut the extractor slot generous enough that I could remedy the problem with a slight turn to he barrel.

The index mark on the barrel was just proud of the mark on the receiver but not past it much more than the width of the barrel mark so the movement was a couple thou at best.

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Originally Posted by Doco overboard

does the barrel extractor cut seem to be off as much off as the front site is rotated

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Just took a look down the action. If I line my eye up to look right down the raceway for the right lugs down to the extractor groove...it looks to be off slightly in the same direction? could be bias too as well now that I confirmed the sight was off.
I also think now that I have the front sight off that my pics, not being perfectly aligned and level, exaggerated the misalignment. I think/hope it will end up being off by about the width of the index marks. You bring up a good point with the alignment of the extractor groove that I hadn't considered yet. Guess we'll have to wait to find that out too!

SS, I think you and Doco are on the right track. I was thinking the same thing about the extractor slot. (maybe I'm stating the obvious here) but With the 03A3 you could just set the front sight to vertical and more or less ignore the index marks. There is a little wiggle room in the extractor slot and it shouldn't be a problem. Actually it will probably center up the extractor in the slot as it seems the error is in the index marks. It wouldn,t be this easy with a 1903 because you have the pinned rear sight to deal with. Salt Flat

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Originally Posted by Doco overboard

the width of the barrel mark

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That would be all the barrel would need to move so maybe not even take it off completely.

OK, here's a thought: Why not file a little off the upper side of the sight key and then shim the other side until the sight lines up? Seems a lot less hassle and risk than trying to twist the barrel tighter (if you even can!). There's a good chance the barrel or receiver will get marred up, where as if you file the sight key.....what's the worst that can happen?

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Originally Posted by ArtPahl

trying to twist the barrel tighte

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It's the other way...barrel is over turned and needs to come back a bit.

OK then. Never mind. Do it your way.

I ordered a 1.225 aluminum bushing, and the lead shims brownells sells for their vise for this purpose - they are .045 thick. This with some rosin should get me nice and snug. My barrel is 1.2 exact - another forum reports a3 barrels are 1.195 - I suppose the extra .005 could be the park finish. Brownells has a 1.2" steel bushing, but being my first time using this vise, I didn't want to chance it slipping with no room for a shim. Others have advised and succeed using an undersized (1.15 or 1.175) aluminum bushing for its malleability.

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Originally Posted by ssgross

This with some rosin should get me nice and snug

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You HAVE rosin? I thought the stuff Brownell used to peddle was unavailable now? What do you have? I need some...

https://www.amazon.com/TOURNA-ROZ-3-.../dp/B009ZALIAC
works for bowling balls. should work for this too. Couple of the other forums I saw mention it being acceptable. Although I doubt I'll need it with a lead shim over clean rough seemingly newly parkerized barrel.
EDIT: quick search found this https://www.midwayusa.com/product/1006358655

Don't know about the bowling ball resin but the stuff from midway would be worth a look.

let me know if they won't ship to Canada. I'll be your resin mule. (Isn't resin one of the hot commodities, along with dirt and paper in the movie "Water World"?)

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Originally Posted by ssgross

"Water World"

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Was one of my favorite movies back then.

I am wondering what is going to happen to the headspace when you twist that barrel. Your OP said the sight was at 11:00. That's 1/12th of a turn (30 degrees). At 10 t.p.i., that's backing off .0083 and, of course, headspace tolerance is .006. The out-of-plum condition is probably not that bad but even at only 10 degrees (which would be hard to notice), that's adding .0027 to the headspace, which is a pretty good chunk of the .006 tolerance.

Is the barrel going to be loose? Will the torque from firing in the RH twist tighten it up again?

I still say move the sight and leave the barrel alone to avoid more problems.

BTW: What about the rear sight? Is that centered with the front sight cock-a-skewed? Are you going to have to relocate that, too?














































btw;

Theirs that much crush at the barrel shoulder and receiver face when the barrel is re-tightened.
I wouldn’t worry too much about it especially if the shoulder is peened or rolled meeting the marks dead on or just proud of them one way or the other.
He’s going to have to do that anyway or it will be way past them I bet.

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Originally Posted by ArtPahl

Your OP said the sight was at 11:00

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That was rough estimate. The point was to stress that it is obviously off. After looking at the extractor groove, I don't think it is nearly that far off. It looks better or worse depending on what angle you look at it or take the picture from.

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Originally Posted by ArtPahl

that's adding .0027 to the headspace

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Thanks for the specs.

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Originally Posted by ArtPahl

What about the rear sight? Is that centered with the front sight cock-a-skewed? Are you going to have to relocate that, too?

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At zero with the skewed front sight, you can see the rear sight location skewed left of center to compensate. Rear sight is easy to adjust/drift on this rifle and I'm not worried about it.
Actually, with some simple trig we can figure out the exact degree of rotation required, using the rear sight offset (easy to measure) and the height of the "A" blade above the bore. Let me measure. That will at least give better than an eyeball ballpark.
Angle = arcsin(D/H), where D is the distance the rear sight is drifted to zero, and H is the sight height.

Its ~6.25 degrees off. Which is indeed enough to notice when looking through the rear sight (drifted .127 left).
For anyone else that finds this, the height of the "A" blade at 1.167 above the bore center.
6.25 degrees is still a ballpark - this assumes the rifle was perfectly level when zeroing and not "canted". But we can figure out that case too.
If it was canted, the rear sight base would have been on an angle. This means the "level" drift of the rear sight would have a lowerbound of cos(6.25)*0.127 = 0.1262ish. Using the previous calculation, a minimum for the amount of cant is ~6.21 degrees.
If you skipped all that, my barrel is between 6.21 and 6.25 degrees over-timed.
My grad. school advisor gave sound advice for presenting mathematics..."never ever do computations in public".
Attachment 114211
so no more than 0.0017361ish increase in headspace.

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Originally Posted by ssgross

the rear sight location skewed left of center

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I'm looking at the rear sight in this pic and see a stake mark/zeroing line on the right side. That must be for alignment of the rear sight at assembly so it doesn't end up too far left? Unless you cranked it over for the pic, it's at zero.

yes. after disassembly and cleaning, I put the rear sight at mechanical center and went to the range and zeroed the rifle. The windage was all the way over to the left when done. I went home and measured the distance the windage had been moved to zero, and drifted the base over that much in order to have the rifle zero with the windage centered. Not surprisingly when I was done, the rear sight then matched up with the original witness marks that you see in that pic. I assumed those witness marks were struck when the rifle was first zeroed. At the factory? It's canted enough to be an annoyance with the 1.whatever inch front sight, and worth trying to fix.

I had an M1 rifle like that years back. Turned out the barrel was bent in the thickest part and had been since the factory. It was a Danish return and near new because no one could figure out why it wouldn't zero and shoot at different ranges. I straightened it and then changed it for a 7.62 barrel. I wonder if this one was the same, it wouldn't zero and so it was shuffled aside. I just can't imagine a factory not catching this or allowing it passed quality control.

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Originally Posted by browningautorifle

I wonder if this one was the same

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I wondered myself if the barrel could have been twisted. I stopped worrying after I shot it and got solid consistent groups.

---------- Post added at 04:30 PM ---------- Previous post was at 04:27 PM ----------

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Originally Posted by browningautorifle

allowing it passed quality control.

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I wonder what the tolerance was. Any variation in timing would be compensated for at the rear sight when zeroing. How much is too much? Perhaps war-time standard was that if the rear sight base could be secured, it was good enough. The cant is mostly noticeable because of how far over the rear sight must be to zero.

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Originally Posted by ssgross

I wonder what the tolerance was.

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Originally Posted by ssgross

How much is too much

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Good questions...

---------- Post added at 01:34 PM ---------- Previous post was at 01:32 PM ----------

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Originally Posted by ssgross

I wonder if this one was the same

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Meaning I wondered if this one was noticed but never sorted out. They had others and just shuffled it to the back rack.

I couldn't resist
https://www.askdifference.com/rosin-vs-resin/
I'm not going back and checking if we got it right/wrong either, tomato tomato.

It's off!!!.
Well, lead shim with aluminum bushing does not work. The lead held the barrel tight, but slipped on the aluminum even with rosin. Vise was clamped on the straight part of the barrel with as much pressure as a 3ft cheater pipe could create.
PlanB worked. The No. 5 bushing (steel) that came with my vise is 1 inch ID. It sits up maybe 3 inches from the receiver. The taper there is less than 0.1. So, I used the lead sheet for the whole length of the bushing, with my bowling ball rosin in between barrel, lead, and bushing. I tightened down with my cheater bar and gave a good sharp yank. Nothing budged. On the second, sharper/harder yank it moved, with a loud squeak sound as it came loose. As I unscrewed it, I could feel a bit of grit from either the park that got in there, or from surface rust.
The wheeler action wrench worked fine. It came with sharp edges all around the upper part that that I smoothed over with a file. I used several wraps of aluminum tape to protect the receiver, but I'll use some of the lead sheet next time, as the aluminum tape left a sticky mess after it was compressed.
Browning, the bowling ball resin looked just like picture of the loose bag on midway's site, and it seemed to work just fine. Maybe this is why brownells gave up stocking it.

I got worried cleaning up the couple the few small marks from where the lead shim squeezed under pressure. It was almost like a glaze on finish. Tried brass brush with oil, no go. Put a fine brass wheel on my dremmel on low speed, painted the surface with kroil. Nylon brush then took off the shiny brass, along with whatever lead marks there were. Threads look good. Phone needs to charge while I clean the sticky off the receiver. Then I'll take pics before reinstalling.
Should I put anything on the threads when re-assembling? I read elsewhere that some people use nickel anti-sieze when rebarreling.
Chuck's how-to thread says no lube, oil creates hydrostatic pressure when tightening, making it hard to get aligned. So I was thinking of assembling dry, then a good soak in some kroil to get down in there, similar to the oil soak it got after the barreled action was parkerized.

We used to use a steel outer shell and poured lead jaws custom to what we were unscrewing. The barrel was grabbed in lead also with rosin and tightened down with a two ton jack in a steel box. The wrench was two bolts with a handle and a set of square outer jaws. I just eliminated the middle man and used straight aluminum so it could deform if need be and was cheaper to make. Usually there's been something to grab, a shape. The long handles help to avoid jerking the receiver. I'd reassemble the way Chuck suggests...dry will be good.

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Originally Posted by browningautorifle

I'd reassemble the way Chuck suggests...dry will be good.

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That's what I done. The final alignment took a little less undoing than I had calculated, I assume because I was generous in my measurement of how far left the rear sight was at zero.
What is more important is the bolt closed, so no extractor groove problems. I then too the extractor off, slid in a no-go gauge, and whatdayaknow, it no go! Threads all looked good inside and out, no peening at the shoulder. Taps on the wrench handle with heavy rubber mallet and it slid right in to position.
Attachment 114383front sight all lined up. Used a hex wrench underneath to make sure I got a good flat reading.
Attachment 114385This was where it was at hand tight.
Attachment 114386Attachment 114387 Final alignment.
Attachment 114388Final headspace on the no-go gauge.
Time to put it back together and go shooting!

EDIT: Not so fast silly goose...you have to slip on the handgaurd ring, rear band, front band, bayonet band BEFORE you put the front sight back on!

One line beside the other, didn't expect you'd have any headspace problem. Certainly not enough to count.

2 thumbs up for my brownells vise. The no. 5 bushing and lead sheet work great, and as a plus over using a larger bushing up on the shoulder I could still view the witness marks. The cheap bowling ball rosin seemed to work fine too.

I bought this rifle several years ago at Cabela's gun library. Whoever priced it thankfully realized what it was. It seemed to be an arsenal rebuild or CMP refurb since all the furniture was a nice, clean, light grey zink parkerized. The straight stock was an unmarked, likely NOS, replacement. It shot OK, but the stock fit was atrocious. Barrel was free floated - no contact at forend, minimal contact behind the lug, and not much wood left to work with. The magazine was contacting the receiver all around.
Thankfully, I had an m1903 parts rifle, 12/42, that came in a replacement A3 scant stock. I've posted about that rifle here - it got a new Minelli stock and so this A3 is trying on the hand-me-down scant. It has more to work with. Shooting and playing with the bedding, if necessary, is next.

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Originally Posted by ssgross

Shooting and playing with the bedding, if necessary, is next.

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So out to give it a wring out? Let's have a look then. Should be fine.