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View Full Version : Newbie Here: What barrel twist for boolits from .22 rimfire cases for AR-15?



tkarl
02-12-2015, 06:18 AM
I have read there are limitations to bullets made from .22 rimfire cases, but cannot find them in this forum. What barrel twist rate do I need if I intend to use BTSniper's tools to make bullets from bulk-ammo .22 rimfire cases for an AR-15 rifle? Let's say I have a 16", chrome-lined, cold hammer forged barrel. Powder loads? Dunno yet. What velocities should I stay within with the rifle barrel described? I think most twist rates of rifles I'm looking at are 1:7. At some velocity limit, as I understand it, the (I made them myself!) boolits will not stay together. Please assist, I'm configuring an AR-15 right now. Thanks.

Nobade
02-15-2015, 12:25 AM
How long are those bullets going to be? That will tell you what twist to use. If they are 55gr. or less, usually a 1:14 will work best. 1:12 might give you a little leeway if you like.

-Nobade

Houndog
02-20-2015, 09:20 PM
If I were building an AR for 22rf jacketed bullets I'd go with a 1/12 twist barrel. While 22rf jackets work just fine, they are thinner than commercial jackets and you will be limited to 50-55 grain bullets unless you have an extremely oversized lead tip.

DCM
02-22-2015, 09:51 PM
A good twist rate calculator here http://www.bergerbullets.com/products/all-bullets/

DCM
02-22-2015, 09:57 PM
Or to really mess with your head there is this old thread http://castboolits.gunloads.com/archive/index.php/t-107867.html