True, but there has to be a demand. Besides, I have a lathe, I might practice myself on Aluminium to improve my skills. Then attempt it on a barrel blank.
I might practice myself on Aluminium to improve my skills.
It would be more to the point to use a piece of steel round stock and do outside diameter and then thread. When it fits correctly you're ready. The hardest might be to grind your chisel for the lathe to the correct width and making the width and depth of the thread correct.
There are folks around who have done it successfully. I don't believe there are a lot of lathes around that are capable of cutting a 3 TPI thread without modification. The left hand thread is likely a blessing. One could cut from the shoulder to the breech end without the need to flip the lathe tool. It should also eliminate that racing-heart feeling as the cutter approaches the shoulder.
It is one thing for an enthusiast to machine a Mk. II barrel shank on a manual lathe, quite another to manufacture barrels. It would no doubt be possible to set up a modern machining center to do the job - but there would have to be the demand.
There are folks around who have done it successfully. I don't believe there are a lot of lathes around that are capable of cutting a 3 TPI thread without modification. The left hand thread is likely a blessing. One could cut from the shoulder to the breech end without the need to flip the lathe tool. It should also eliminate that racing-heart feeling as the cutter approaches the shoulder.
I know that feeling well! The left-hand thread is indeed a blessing, and possibly why it was chosen (that, or simply another example of Sir Charles being contrary again just to spite the world.) My trade test as a graduating apprentice was a left-hand thread: double-start, square thread, with a matching nut. They cut open the nut to make sure you didn't lap it in after the fact. I don't remember the pitch exactly, but it must have been close to 3 TPI.
It is one thing for an enthusiast to machine a Mk. II barrel shank on a manual lathe, quite another to manufacture barrels. It would no doubt be possible to set up a modern machining center to do the job - but there would have to be the demand.
Tiriaq's correct when he says it's quite doable on a manual lathe, given the right gearing. You'd need a rifled blank big enough to accommodate the Ross profile, but they can be had. If you want to duplicate the original Ross barrel exactly, the profile could be reproduced using a tracer attachment. For a skilled machinist with the right equipment, producing replacement barrels for the Ross from rifled blanks would be no more difficult than any other precision machine part. BUT, could it be done profitably? The demand for Ross barrels, compared to modern AR's, or even Mausers, is not large enough to support continuous production. It would be occasional small runs only. CNC can accommodate batch runs quickly, but that's once the programming and tooling have been finalized, and it's the programming and tooling that take the time. Time is money; no commercial operator wants to spend that on something with such a limited demand.
I did meet one guy at a show some years ago who sold engine adapter kits. He had them CNC'd in batches at a commercial shop, using the program and tool design that had been done for him, as a class project, by a senior student in the AMT program of his local community college. The student made the program, ran off one sample for his course, then turned over a couple of copies with the tool specs. All the time-consuming work was done, so all the CNC shop had to do was load the programming, install the tools, and keep feeding the machine with material. The batches worked out very economically. Unfortunately, this will NOT work for gun barrels. You won't find a trade class anywhere in this country that doesn't have a zero-tolerance ban on working on firearms components.
True, but there has to be a demand. Besides, I have a lathe, I might practice myself on Aluminium to improve my skills. Then attempt it on a barrel blank.
I'm afraid machining aluminum, even stronger alloys like 7075, won't really prepare you for the problems you will face machining chrome-moly. You need to go straight to steel, even if it's only low-carbon mild steel. You'll still find that far simpler than the real thing, but it's a start. I don't know specifically what thread form is used on Ross barrels. If it's something standard, say Acme, then don't try grinding your own threading tool. Get yourself a good, rigid, insert tool holder that will take carbide inserts of that profile. Trying to grind your own out of HSS without the use of a comparator (or modern whiz-bang equivalent), and get the profile right, will drive you to switch to stamp collecting. Even if you do get the profile right, it won't have a great edge life on chrome-moly.
Been watching this chap who has a machine shop his grandfather started the shop, then his father and finally the son so 3rd generation machinist he does some pretty good stuff maybe getting in touch with him think its called Booth Machining goes under the nik on you tube Abom79 has done nearly a 1000 vids on different stuff with machining no CNC just lathes and shapers. Here is one of his vids just as a point of contact hope he can help seems a pretty genuine chap.
The reason I said practice on aluminum is it is much easier to cut and I have lots of leftover stock. I do understand there is a difference between chrome moly and aluminum.
PM
Originally Posted by Sharpshooter1944
