View Full Version : NOOB - AR question - 55gr vs. 64gr.

03-20-2012, 12:18 PM
Total Newbie to the AR world. I haven't even gotten my Stag Model 3 out of jail yet.

I am looking to buy some ammo and was wondering, is there a performance difference between a 55gr bullet and a 64 gr bullet? I can get a deal on the 64 grain bullet but don't know if there is any type of issue with shooting the 64 gr bullet through this rifle. I shoot different bullet weights through my 30-06 without issue, is it okay to do this out of an AR?

Any advice is greatly appreciated!!

gun toting monkeyboy
03-20-2012, 12:43 PM
It is fine. If your rifle has at least a 1-9 barrel, you can shoot them with no problem at all.

03-20-2012, 12:44 PM
What he said^^

03-20-2012, 1:06 PM
Thanks guys!!

Calgunners ROCK!!

03-20-2012, 1:49 PM
Theres some chart out there but basically its like below.

1-7 twist, heavier bullets 70gr+
1-8 twist, mid range 50-70gr
1-9 twist, liter bullets 55gr and below

03-20-2012, 1:57 PM
I think the 1-7 twist is okay for down to 62 grains and not bad for 55 grains?

03-20-2012, 2:26 PM
1-7 is a bit fast for the lighter bullets. 1-9 is a bit slow to stabilize the 75 grain and above, but some have had sucess with them

03-20-2012, 2:38 PM
I kind of use this as a guide line.... just to give you an example, my 24" long stainless barrel AR with a 1:8 twist rate does so well with 55gr rounds it almost contradicts this chart a little... End if you day, you just have to try it out and see what works best for you.


gun toting monkeyboy
03-20-2012, 2:46 PM
1-7 will stabilize 55 grain bullets just fine. You can use them in that twist barrels with no fear of them flying apart or anything like that. I wouldn't go below that with jacketed bullts though. There have been cases where that 1-7 twist overspins lightweight varmint bullets to the point that they literally fly apart after they exit the barrel. Not good for accuracy, to say the least. It doesn't happen all the time, nor with every kind of bullet. But it seems to have happened to enough people that I would try to avoid it. If you want to go lighter than 55 grains in a 1-7 twist barrel, I would stick to the solid copper bullets like the Barnes TSXs and such. They are longer than similar weight bullets made of copper and lead, which helps prevent them from becoming "over-stabilized". And they are a solid chunk of copper, which makes it that much harder to spin apart.


03-20-2012, 5:55 PM
54, 55 pretty much same. Don't worry, just shoot it

03-20-2012, 6:44 PM
Your stag is a good rifle
You will be just fine

03-20-2012, 6:55 PM
I have been shooting 55 grain out of my 1/7 and its been okay. I am looking forward to using some different grains to see the difference in the shots.

03-20-2012, 7:32 PM
54, 55 pretty much same. Don't worry, just shoot it

It was a typo on my part...I meant to say 64 gr, not 54.