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View Full Version : which barrel to keep


vincentvangerven
July 7, 2008, 05:33 AM
First; A friendly hello to all from Europe :)

Guys, i got a question here, you might be able to give some advice about the following: i bought 2 green mountain 25 inch barrel blanks in .22 caliber.

One is a 1:14 twist wmr barrel, this one;
http://www.gmriflebarrel.com/product...aspx?id=324059

the other one a 1:9 5.56 ar15 type barrel, this one;
http://www.gmriflebarrel.com/product...aspx?id=324057

I'm planning to only shoot SUBSONIC .22lr rounds, with bullets in the 40/50 grain range at 100 yards.

So here comes my question:

Which barrel to would probably perform best at long range. Did a little bit of testing and at 40 yards & they both group well with 42 grain roundnose bullets, but didn't have the time nor space to take a few long range shots.

I'm trying to predict which barrel has the best chance of performing well with subsonic rounds at distances up to about 100 yards.

Will the 1:9 twist spin the bullet to fast at longer ranges, loosing accuracy, or will the 1:14 be too slow to stabilize the bullet at longer ranges?

Looking forward to your input, with kind regards, Vincent

Scorch
July 7, 2008, 02:15 PM
Well, truly and honestly, neither of those barrels are intended for 22LR, and neither will shoot to their full potential with 22LR ammo. 22WMR uses a .224" diameter bullet, 5.56X45 uses a .224" bullet, but 22LR uses a .222"-.223" bullet, so the bullet will not fit the bore properly and could cause some shot dispersion. In addition, the 1:14" twist is a little fast, and the 1:9" twist is way too fast for a 40 gr 22 LR bullet. My recommendation would be to get a barrel actually intended for 22LR and use that. Since you are looking at Green Mountain Barrels, get one of their barrels made specifically for 22LR.

vincentvangerven
July 7, 2008, 05:56 PM
ok, thank you for your reply. Kinda got confused on the bullet diameter , on this page it says .22 lr bullets are .223 above, but then lower it says .224 diameter....

http://en.wikipedia.org/wiki/.22_Long_Rifle

scroll down for a tech drawing wghere they quote .224

That's why i thought a .224 groove barrel should work. (and at least out to 35yards it does, one ragged hole)

Ah well, just gotta shoot some more at longer distances, then we'll find out.

Cowart
July 9, 2008, 03:42 PM
FWIW, normal twist for a 22lr is 1:16