AR Question

[robertboyd]

I'm new to AR's and heard someone say that 55 grain 223 ammo won't give the best accuracy in 7:1 twist barrels. What do y'all think?

[BigMouth]

Depends, better would be 8:1 and best or standard would be 9:1 for a 55 gr round. My 7:1 shoots some 55 gr pretty good and others not well at all it lves the 75 & 77 gr pills from Sierra and Nosler. . Anytime you buy a gun you should take a good selection of ammo out and shoot groups to determine which one your firearm shoots best. Good luck!

[NoCAL]

If you are looking for minute of angle, 55 grain might not be the BEST choice but it will still work fine. It's basically all I shoot, I have 7, 8 , and 9 twist barrels. 55 grains seems to be the one weight that will shoot pretty good in all of them. Have never tried larger than 62 and have no use for 40.

NoCAL

[WVBullet]

My match grade barrel is 1:7 and I use 55gr. Its a tack driver.

[berudd]

It will probably shoot just fine but in general faster twist rifling is to give better accuracy with heavier bullets. 1:7 is, I think, the fastest twist rate for an AR so it will be best for the heaviest bullets like 77 - 80 grains. 1:9 is more ideal of 55 gr bullets. I think you can end up with over stabilization with 55 gr bullets in the 1:7 barrel but I'm not real sure what the effect of that would be. It would likely only become a problem at longer ranges. Also, when talking about accuracy its good to consider how much accuracy you really need anyway. If you're shooting gongs at 300 yards you might want more accuracy than shooting paper targets at 25. A lot of people well get all crazy about having the utmost in accuracy when all they are doing is occasionally shooting paper targets a short ranges.

[BigMouth]

Should have asked what you're using it for, plinking, home defense, varmits or something else like precision shooting?

[robertboyd]

I will probably be using it for plinking and varmits - anywhere from 50 to 200 yards max. I have another centerfire for 200+ yards.

[dtibbals]

I will probably be using it for plinking and varmits - anywhere from 50 to 200 yards max. I have another centerfire for 200+ yards.

I would run a 9 twist if that is what you want to do with it. Will shoot the 55g and if some varmint loads will be 40 something grain bullets and you can throw those as well, if strictly varmint I would go 12 twist. Most all barrels short of high end match barrels are going to be 7 or 8. 7 is what the military uses so everyone thinks that is best but they use 3 very specific bullets for the most part. Budget will dictate what you buy but I wouldn't go faster than an 8.

[BigMouth]

You'll probably want a 18"-20" or longer barrel and 9:1 or 8:1 twist ratio, I'd lean 8:1. That will let you reach out with bullets between 35 an 77+ grains. Barnes makes a bullet called the Varmit Grenade" that is absolutely devastating on small critters. Its a fragmentation bullet that in almost all cases will not ricochet.



https://m.youtube.com/watch?ipadtype...ient=mv-google

[dtibbals]

Also I have a varmint rig for shooting prairie dogs and it is a 20" match grade barrel. I built the rifle for this one purpose, it is a 7 twist but I shoot 77-80 grain bullets but I stretch it out further than you could using the 40g varmint bullets. I can make 400-600 yard shots all day long with the heavier bullets. Past 600 and I get out a 6.5MM bolt gun and run that out to 1k and more. Inside of 100 yards and I shoot a 22LR...all 3 of these rifles are suppressed.

[BigMouth]

Also I have a varmint rig for shooting prairie dogs and it is a 20" match grade barrel. I built the rifle for this one purpose, it is a 7 twist but I shoot 77-80 grain bullets but I stretch it out further than you could using the 40g varmint bullets. I can make 400-600 yard shots all day long with the heavier bullets. Past 600 and I get out a 6.5MM bolt gun and run that out to 1k and more. Inside of 100 yards and I shoot a 22LR...all 3 of these rifles are suppressed.

I'm jelly.

[StratDude]

2 of my Colts have 16" 1 in 8" twists and the other has a 16" 1 in 9". I use 55gr Noslers in the 9" twist and the accuracy is incredible. I use a suppressor on the others. I load a subsonic round for them with 77gr Sierra Match bullets and I'm impressed with the groups they've been producing.

[PSM207]

Regardless of twist rate, if you do not have a quality barrel and shoot quality ammo this topic is pointless. I personally have a 1:7, for it's ability to stabilize longer bullets.