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m1943
10-21-2012, 03:34 AM
Hi all. Haven't been on this forum for years now. Here is my question:
If I am going to make a barrel insert on a lathe, what sort of steel should be acceptable, do I look at Rockwell hardness only, or are there other factors??
I am looking at three calibers: 9x17mm (.380), .32 ACP and .22 LR. Nothing particularly demanding, but still I want to do it right. I don't want to put any extra stress on the existing bore, or I want to minimize it, so the insert should be able to contain the pressure of the cartridge in its own right. Bore diameter is about 0.45 in.
What Rockwell hardness is required for a a barrel/barrel insert, or a cartridge adapter?
Thanks

Diesel
10-21-2012, 05:50 AM
Years ago you could buy these inserts cheaper than you could make them...10/40 should work just fine...but I've never made aninsert to sub caliber a round. Good Luck, welcome back.

Diesel 88888888

:coffee:

deth502
10-21-2012, 11:34 AM
if you do not plan on doing your own rifling, and plan on staying legal, you will be limited as to what materials that you can buy barrel blanks in.

m1943
10-21-2012, 01:40 PM
if you do not plan on doing your own rifling, and plan on staying legal, you will be limited as to what materials that you can buy barrel blanks in.
Well, I was going to inquire about rifling next, but since you've mentioned it, what's the connection between stying legal and doing/not doing my own rifling?
I was not intending to use a bore blank, I have a lathe and would like to turn my own barrel insert. I am thinking of going the .32 acp route, or might try .380. This used to be a 7.63 Mauser-chambered weapon, but currently has a shot-out .45 in bore. Don't ask.

deth502
10-22-2012, 05:56 AM
Well, I was going to inquire about rifling next, but since you've mentioned it, what's the connection between stying legal and doing/not doing my own rifling?
I was not intending to use a bore blank, I have a lathe and would like to turn my own barrel insert. I am thinking of going the .32 acp route, or might try .380. This used to be a 7.63 Mauser-chambered weapon, but currently has a shot-out .45 in bore. Don't ask.

unless your making a shotgun, and have the gun apply to all shotgun regs, and not have any other firearm that the inserts can fit into that do not fit into shootgun regs, then they will have to be rifled. any pistol or rifle barrel must have rifling.

you need it to keep the projectile accurate, but if you really dont care, there are no regs as to how deep or how many lands/grooves there needs to be, so a few deep scratches/gouges should be ebough to keep you legal.

Helen Keller
10-22-2012, 10:44 AM
look at all the more rifling these .410/45 revolvers have in them.

m1943
10-23-2012, 12:36 AM
unless your making a shotgun, and have the gun apply to all shotgun regs, and not have any other firearm that the inserts can fit into that do not fit into shootgun regs, then they will have to be rifled. any pistol or rifle barrel must have rifling.

you need it to keep the projectile accurate, but if you really dont care, there are no regs as to how deep or how many lands/grooves there needs to be, so a few deep scratches/gouges should be enough to keep you legal.
Wasn't aware of this part of the law, but I WAS going to look into rifling next. In the mean time, I need Rockwell hardness/steel type that would be acceptable for my purposes. With the outer diameter of the insert being roughly 0.45 in, I need to choose between a .380 and .32. The latter is safer, the former - more effective and available.

nikko
01-01-2013, 05:50 PM
read LAST OF THE MOUNTAIN MEN, on a way to make a mandel and rod for hand cutting rifling. also reach THE SUBMACHINEGUN, Vol I, by Bill Holmes, for his way of doing it. best to just turn down the OD of a rifled hunk of barrel, man, then epoxy it into the bored out barrel. Google for Brownell's Supply, call them, get PAST the know nothing ordertakers and talk to the REAL SMITHS who work there. also, google for GunParts Corporation, they have a forum, and for HomeGunsmithng Forums.

Schuetzenman
01-03-2013, 01:26 AM
4140 or 4150 chromemoly steel with a RC of 32 to 35 is what is used in most smokeless powder barrels. For once I agree with something nikko has said. You would be better off getting a barrel blank that has rifling in it and just turn it down to fit in your bored out barrel. Brownell's sells drill bits for boring out worn out barrels as well as reamers to smooth up the bored out hole. I think they might have rifled insert barrels, seems years ago I remember seeing them in the catalogue for smaller calibers down to .22 lr.