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dealdan
04-23-2021, 12:44 PM
Hello folks, I am looking to start a new project. My dad had an old martini cadet action and I want to work towards putting together a complete rifle. I have settled on using 32-20 for the caliber. However I am having some troubles finding a barrel. Green mountain barrels has a barrel they say is suitable for 32-40 but I think that caliber might be too long for the action. the issue lies in the twist rate. The 32-40 barrel is a 1:14 twist. (the 32-40 barrel isn't chambered, its just the caliber they recommend)

My question is, will 1:14 work for 32-20?

If not, does anyone know a source for a barrel that would work? I would prefer an octagon barrel, but I'm not completely set on that. I just think that would look better on an old single shot

Outpost75
04-23-2021, 03:14 PM
The .32-20 uses a a barrel of nominal .310-.311" groove diameter whereas the .32-40 is .320", so you don't want a .32-40 barrel unless you wanted to restore the rifle to its original .310 Greener chambering, using fireformed .32-20 brass, lengthening the chamber from the .310 with a .32-40 neck and throater to use an inside-lubricated bullet. That cartridge is the 8x32R and was fairly popular to rework the Cadet rifles to use common brass.

A .32-20 will work just fine with a 14-inch or 12-inch twist using a common .308 groove diameter barrel and will let you load up to 150-grain bullets with good accuracy. I used a 10-inch twist M1 Garand pull-off to do a rifle in .32 S&W Long and been pleased with the results.

281810

I would worry much less about the twist rate of the barrel, than having a barrel of good quality and having the work executed skillfully.

ulav8r
04-23-2021, 09:32 PM
https://www.gmriflebarrel.com/ak-blank-20-x-1-7-62x39mm-gunsmith-edition-raw-blank-4140/ is the blank I intend to use for 32/20. It is a 9.5 twist but the groove diameter should be perfect. Currently out of stock but I have two in the garage, one definitely reserved for a HandiRifle, the other may become a couple of pistol barrels.

P.S. https://www.gmriflebarrel.com/ak-blank-h-7-62x39mm-24-x-1-375-heavy-gunsmith-edition-raw-blank/ also out of stock but 4 inches longer.

P.P.S. Finally acquired a 32/20 reamer yesterday. Had a great day flea marketing.

Outpost75
04-23-2021, 11:06 PM
It sounds like your plan is coming together. This is the heavy bullet which I use in the .32 S&W Long rook rifle which is also stable in the .32 Colt New Police revolver with 14-inch twist at about 700 fps using 6 grains of #2400 or 7 grains of IMR4227 powder.

Penetration is simply astounding with no evidence of tipping.

281820

dealdan
04-24-2021, 10:41 AM
Okay so it sounds like a 1:14 twist will work okay but the 30-40 barrel might be the wrong diameter. I'm confused how w 7.62 barrel could work considering that 7.62 is basically 30cal.

I realize this project will be a fair amount of work and take a fair amount of time so the last thing I want to do is get it all done and find it doesn't shoot well.

Outpost75
04-24-2021, 12:32 PM
Okay so it sounds like a 1:14 twist will work okay but the 30-40 barrel might be the wrong diameter. I'm confused how w 7.62 barrel could work considering that 7.62 is basically 30cal.

I realize this project will be a fair amount of work and take a fair amount of time so the last thing I want to do is get it all done and find it doesn't shoot well.

Barrel groove diameter and twist really don't matter much within reason. A 7.62x39 blank will work, as would one for a .30 M1 carbine. Just select a bullet suited for the barrel dimensions and twist rate. Quality of the barrel, skilled execution of the work, and chamber dimensions having adequate release clearance for the chosen bullet and fitting the bullet to the ball seat and origin of rifling are most important.

ulav8r
04-24-2021, 01:33 PM
The 7.62x39 blanks I listed are supposedly .311 groove diameter.

John Taylor
04-27-2021, 09:14 PM
I have used the 7.62X39 barrels for 32-20 and 32 S&W. Also a 303 brit will work.

indian joe
04-27-2021, 11:28 PM
There's been more than a few rotted out 32/20's rebarrelled downunder using 310 cadet tubes - they were a dime a dozen in the 1960's - $7 for a complete rifle take yr pick out of the bin when I was a kid.