1:8 twist 22" bull barrel AR

[SSN Vet]

I completed my budget Varmint AR build earlier this year and couldn't resist the smoking deal I got on a Wilson 1:8 twist 22" bull barrel.

So far my best groups are 0.74" @ 100 yds with 55 gr. Hornady Z-max (A-max with green tip and cannelure) and H322, which isn't too shabby for a $600 project rifle, imo.

I'd like to try some heavier projectiles to see how far out there I can "reach out and touch" targets.

Any thoughts on whether this barrel will stabilize 75 ro 80 gr. projectiles?

 

[Ifishsum]

It sure should...69 SMK, 75 HBTHP and 77 SMK all should shoot well loaded to magazine length. Most of the 80+ bullets need to be loaded long and single loaded for best accuracy. Ballistically, the 80 SMKs have a small advantage with wind drift at long ranges (500+) but otherwise the 77s shoot just as well for me. Usually driven by Varget or RL15

 

[JimKirk]

Just looking at the Hornady web site ... appears they no longer list the Z Max at a 55 gr in .22 caliber ... looks like 50 gr is it now ....

I shoot lots of the V-max(50, 55 & 60 gr) and have shot a few Z-Max 50gr out my 16" bull barrel .... they shoot really good ... I need a better trigger to get down to your group size ... about a solid one inch is the best I can squeeze out of my rough trigger ...

 

[Actionjrs]

It will probably stabilize 77 no problem but try it and see.

 

[Blue68f100]

The heaviest that would fit the mag would be 77gr. Give the 69gr Sierra Matchking a try.

 

[MtnCreek]

77 smk or cheaper hornady 75 hpbt with h4895 or IMR8208 should give good accuracy. 1:8 will stabilize either just fine, even in shorter barrels than yours.

 

[farmerboy78]

It will definitely shoot the heavier bullets, I have a 1-8" twist and it eats up 77gr nosler cc over 23.6gr ramshot tac

 

[Rangemaster]

77 smk or cheaper hornady 75 hpbt with h4895 or IMR8208 should give good accuracy. 1:8 will stabilize either just fine, even in shorter barrels than yours.

75gr with 4895 I tried this myself and they where really compressing the loads and the seater die would ring the bullets.

 

[SSN Vet]

thanks for the replies...

I already load the 69 gr. SMK and my 1 in 9 twist 16" HB middy shoots them very well.

I'll give the 77 smk a try in the new 1 in 8 22" bull barrel build.

 

[Bart B.]

Sierra's 80-gr MK should also shoot well from 1:8 twist barrels. So says their website.

A 22 inch barrel with a 1:8 twist may well shoot Sierra's 90-gr. MK bullet. But only with single round loading as it'll need to be seated out too far for most magazines to feel well. Slower powders need to be used, too. Sierra states a 1:6.5 twist for this bullet but that's from a short AR typical barrel at 16 inches. Muzzle velocity increases about 25 fps per inch for the .223 in these barrels.