What bullets for 1-9 twist AR?

[Grassman]

So this also ties into the reloading supply issues we are having now. What would be the heaviest bullet I could shoot in my 1-9 twist 18" barrel AR? Finding bullets has been tough, but some heavier end bullets can be found. What powders would also accommodate the heavier grain bullet?

 

[ironworkerwill]

Light bullets will shoot best from 1/9 55gr and such. heavy bullets 65 gr and up need more twist to stabilize the bullet.

 

[ironworkerwill]

well really you can shoot them all. I have seen slow twist bbls shoot heaver bullets fine but not drivin tacks. how far do you plan to shoot?

 

[rcmodel]

1/9 should handle any bullet weight up to 75-77 grain match bullets.

rc

 

[Grassman]

1/9 should handle any bullet weight up to 75-77 grain match bullets.

rc

So a 75 to 77 grain bullet would be max?

 

[Ramone]

I keep going back and forth between Benchmark and Varget for .223- While Varget *might* have an edge with heavier bullets, I haven't seen a clear advantage.

In my 1:9 barrels, I have had best results with 68 & 69 gr SMKs, and 50 gr Varmint Grenades (be aware that the LENGTH of the projectile is the variable you are concerned with, so a 50 gr all copper bullet at almost the same length as a 69 Lead/Copper SMK works just fine in a 1:9 )

 

[ApacheCoTodd]

1:9 is an excellent compromise twist for a shoot all as the military rifles have spanned from 1:12 to 1:7 and only those extremes display displeasures with offset extremes in projectile weights.

1:9 - it's the "small block Chevy" of AR twists.

 

[armoredman]

My 1-9 twist likes 55 grain just fine, but seems to really like 60-62 grain.

 

[gotigers]

My 1-9 shoots 68 just fine. I've not shot heavier with it. mid 40's to high 60's. It does like 55 the best. Especially, hornady steel match.

 

[Nanook]

I have a box of 69 grain Sierra Match Kings on my bench. Right on the box it says "For 7 to 10 twist barrels only".

1 in 9 twist does very well with 69 grain bullets from my Savage bolt gun.

 

[Lerk]

Mine rather likes 62gr but will handle the 68gr as well just fine, but anything about that an consistency starts going down for some reason.

 

[ricebasher302]

I have achieved my two tightest groups with 40 grain and 68 grain pills. Not out of an AR, but a 1:9 CZ .223.

 

[stolivar]

My 1-9

does not like 45 grainers



steve

 

[nipprdog]

heavy bullets 65 gr and up need more twist to stabilize the bullet.

Not true. Many of us have excellent results with 68 and 68 grain. Some with 75 gr.

 

[ngnrd]

While I've heard that some 75gr bullets will work in some 1:9 barrels, I know that the 75gr Swift Scirocco's will keyhole when fired out of my Remington R-15 VTR.

So... there's that.

 

[Grassman]

While I've heard that some 75gr bullets will work in some 1:9 barrels, I know that the 75gr Swift Scirocco's will keyhole when fired out of my Remington R-15 VTR.

So... there's that.

That's the gun I have.

 

[Ramone]

GUYS!

lets bear in mind that velocity plays a role, as much as Projectile Length, and rifling rate.

 

[ngnrd]

Well, I wasn't shooting over the chrony, so I don't know what velocities I was getting. But I was starting to get flattened primers when I got near the listed max load. So, I know that I wouldn't be able to push those long, pointy 75gr Scirocco's much faster anyway.

 

[boommer]

69 tops in a 1-9 for any longer ranges as far as powders go H4895 then BLC-2 varget.

 

[ohwell]

55's work well out of mine but it really likes the 60 grain bullets

 

[amprecon]

In my personal experience with my DPMS Lite, I bought 50gr., 55gr., 60gr., 62gr., 69gr. and 72gr. Hot and cold, it definitely shot the 55gr. the best.

 

[Skylerbone]

I shoot an RRA with a 16", 1:9 twist and it likes 55 and 60 gr best at near max loads using Varget or BL-C(2). Tried Nosler, Hornady V Max and Sierra and all do very well.

I didn't buy it as a precision rifle but groups are typically .75" at 100 with a 3-9X Leupold, good enough to not be overly particular about bullet selection. Not calling anyone out but many shooters who believe they're witnessing a keyhole are actually seeing a tear from an unsupported target (no or shot out backing). This, more often than not in my experience.

 

[ngnrd]

I know what keyholes are... and these were definitely keyholes. The targets were stapled onto 1/2-inch plywood, and none of the 4 other loads I shot that day had any signs of keyholing - just the 75gr Scirocco's. These are the longest bullets I've shot out of that 1:9 twist barrel, and even at about 50-cents each, I was really hoping these high BC bullets would stabilize so I could start working up accuracy loads. But sadly, they don't. Now, I'm trying to get my hands on some 62gr Scirocco's to test. But the way the buying frenzy is going, it may be June before that happens...



EDIT: For the record... Before I paid $50 for a box of 100 of these bullets, I found conflicting information regarding whether or not 1:9 would actually stabilize them. I even talked directly to Swift, who basically said that this combination was right on the ragged edge, and that they've heard that some rifles would shoot 'em, and some wouldn't. So, I knew I was taking a chance. Other people may have different experiences. This is my experience.

 

[45lcshooter]

50gr-69gr. Any thing bigger than that, the bullet wont stablize through the air, and it will wobble and egg the hole on paper target.

 

[ironworkerwill]

^^ Since we all seem to be divided. 1/9 is the catch all of .223 rates. It will shoot most bullets well. It may not shoot long or heavy bullets well over long distances. Thats why I asked how long the intended range range will be. Just because it stacks 70 grainer in one hole at 100 yds don't mean it wont wobble and keyhole at 400. www.chuckhawks.com/rifling_twist_rate.htm

twist rate= 3.5*velocity0.5*diameter2/length