Bullet weight for my AR-15

[MICHAEL T]

I have a 1 in 9 twist and would like to know best weight bullet for that rifle.

I will keep my shooting max 200 yds where I live

 

[badkarmamib]

1:9 is best designed for around 55 grains. Can go up to 62, or down to about 50, but accuracy won't typically be as good. But, as always, rifles don't always follow the rules, so you can experiment.

 

[otrman]

Some 1/9 will shoot 75 gr well and some won't. Only way to know is go shooting and find what it likes.

 

[Reloadron]

It's not just about twist verse weight as bullet shape is important also. As to a 1:9 twist? The 1:9 is a good general purpose twist. Bullets like the Sierra 69 grain Match King fare well with the 1:9 twist as well as a wide range of other bullets.



You can try heavier bullets and see how they shoot in your rifle.

Ron

 

[Hardtarget]

My gun is a 20", 1:9 twist also. I've tried several bullet/powder/primer combo's

I got some good coaching here to smooth over my rough spots.

My gun does seem to like the 55 gr offerings and I've even gotten some decent 100 yd groups with Hornady 55 gr fmj.

Recently I tried a bullet from Hornady that my gun shoots good. Its a 62gr BTHP. I tried several loads and found one that gave me a three shot"mini group" of .7" and one of .8" shot from bags @ 100 yds with a 4.5 power scope. I've loaded several rounds to shoot at 200 yds just to see how they (and I) can do.

Hopefully you reload so you can try and test different loads. Its fun to look around and play with it. More range trips! Always a plus.

Mark

 

[Snowdog]

I've wondered about this myself. I currently have a Palmetto State Armory carbine with 1:7 twist 16" barrel and a M&P Sport II with 1:9 and both seem to like M193 (55gr).

However, both also like Prvi's .223 75gr BTHP and Silver State Armory's 5.56 77gr (Sierra) OTM. Groups are as tight as I can shoot with iron sights. All holes are perfectly circular.

I suppose with some decent optics I might notice a difference at greater ranges, but I'm quite please with the results I'm getting with both the 1:7 and 1:9 with 55gr to 77gr projectiles.

 

[jmr40]

A 7, 8 or 9 twist will usually do OK with the most commonly seen bullet weights. Most anything from 50-65 gr should do OK in any of them. The 7 twists will be a bit better with weights heavier than 65 gr, the 9 twist should do better with bullets lighter than 50 gr.

 

[HKGuns]

It depends on the distance the rifle and the bullet.

69gr should be a safe bet in that rifle at most effective range of the round.

 

[benEzra]

The 1:9 was intended to shoot anything between 40 and 69 grains, AFAIK; 69gr boattail match loads will probably be the best for long-distance shooting, but it will depend on the individual rifle. 1:7 is advised for anything heavier than 69gr.

 

[nastynatesfish]

 

[RecoilRob]

If you're only shooting out to 200 yds, then there's no benefit from the heavies unless your particular rifle shoots them the best. My 1:9 Varminter loves the flat-base 53 gr Sierra Matchkings which would easily go 200 with minimal drop. Going to the real heavy bullets will only slow them down and make the trajectory a bit loopier...though they'll still be pretty flat shooting as that's not long distance at all.

Maybe experiment with several different bullets and choose what shoots the best regardless of weight? For some reason the flat-bases seem to shoot very accurately when compared to boat-tails though they're a bit less easy to load it's no big deal.

 

[redneck2]

My 9 twist does well with 68 grain Hornady HPBT's. Best load is 50 grain Nosler BT's over Varget.

 

[Grumulkin]

I have several 223s and one has a 1:10 twist barrel. The best load I have for it is 77 gr. Nosler BTHP bullets over RL-15. The load has also worked well in 1:9 and 1:7 twist barrels.

Another "heavy" bullet I use is the Speer 70 gr. Semi Spitzer. I've used it on deer with a 222 and a 22-250 with 1:12 twist barrels.

 

[RainDodger]

I have a Wylde-chambered 1:9 and it is absolutely addicted to 60 grain Sierra "Varminter" (#1375) bullets. No kidding, I went from baseball-sized groups with other loads, to sub-MOA groups when I tried these. I've had great luck with both 24.1 grains of H335 which chrono out to 2820 FPS and 25.0 grains of H335 which my chrono (MagnetoSpeed) shows at 3006 FPS.

 

[FL-NC]

Most of my AR's have 16" 1/9 barrels. I have had no issues with stabilizing 75 grain Hornady BTHPM and MK 262 (77 grain black hills OTM) from any of them. What I have had is excellent groups with these match grade rounds. Also did the same with a 1:9 in 20", and 1:7 in 10" and 14.5" when I was in the mil. My preferred round for "non-precision" shooting (plinking) inside of 300 yards is 55 grain PMC- and guess what- never had issues with these rounds either! The groups were bigger (cheaper 55 grain ammo- go figure) but not out of control big groups or anything. The only guns I ever saw key holing with were older M16A1/ AR15 SP-1's and AR180 rifles firing heavier bullets like green tip.

 

[kwg020]

Most of my AR's have 16" 1/9 barrels. I have had no issues with stabilizing 75 grain Hornady BTHPM and MK 262 (77 grain black hills OTM) from any of them. What I have had is excellent groups with these match grade rounds. Also did the same with a 1:9 in 20", and 1:7 in 10" and 14.5" when I was in the mil. My preferred round for "non-precision" shooting (plinking) inside of 300 yards is 55 grain PMC- and guess what- never had issues with these rounds either! The groups were bigger (cheaper 55 grain ammo- go figure) but not out of control big groups or anything. The only guns I ever saw key holing with were older M16A1/ AR15 SP-1's and AR180 rifles firing heavier bullets like green tip.

Are you reloading the 75 grain Hornadys? If so what powder are you using?
kwg