I have struggled with what Cartridges I can safely use in my Ar-10. I have reviewed a lot of sites and it talks about the 358, 308, 300 wsm, and about 15 others. I have stayed with NATO round due to my ignorance. Can you please give a list of off the shelf shells I can use?
If your AR-10 says 7.62 or 7.62x51 it is .308, it should say on the barrel and or the action.
Yup, what he said. Thanks.
In general the barrel of your rifle is stamped with not only the chambering but the twist rate of the tube. Of course as I typed this I looked at the original 1980 something Armalite AR-10 tube I pulled off the rifle and it says nothing?!?!? I think if it was a firearm built as a unit it will state what it is on the receiver and possibly the barrel but if it is a parts gun it should have the barrel stamped. As noted some times there is nothing. If the rounds that you have loaded and fired come out looking like the rounds you loaded and you are accurate on the target chances are you have found the right chambering. 7.62x51 or 308 Winchester is by far the most common round in the AR-10 platform but there are many as you have seen that it CAN be chambered for. You CAN shoot a 308 in a 30-06 but it will blow out the brass to which you can trim it down to make any one of various 45 cal cartridges. You can shoot a 270 in a 30-06 but you cant chamber a 30-06 in the 270 because the bolt wont close. Manufacturers are very particular to ensure you cannot chamber an over size boolit in an undersized bore. That is why there was a delay in the 7mm WSM release as it was determined you could chamber a 300 WSM in a 7mm WSM chamber, things had to move around to prevent stuffing a 30 cal boolit down a 7mm tube.
If you don’t know what your rifle is chambered in you should really have a gunsmith “cast” the chamber and tell you for certain, the medium is called "Cerro Safe and once poured into your chamber will provide you all manner of details as to your chamber, land, leade, shoulder angle and depth which will allow you to make custom performance ammo for it. I do this for my high performance custom guns that only eat precision ammo that I make as I find it cuts my load development time down by half as I already have all the critical dimensional numbers prior to starting the load research.
7.62x51 is a .308 win, or at least are close enough to be interchangeable for this application.
@Brian176 Sorry about the typo on the first post, got my Russian and NATO .mm mixed up. And I have shot both.
So with the other posts did that answer your question? Any .308 Hunting or Defensive round will fire in your AR10. Do you hunt? Or are you looking for defensive rounds?
I am not a rifle shooter, but I do read about them, and I recalled reading something on .308 v. 7.62 recently. I found the article, it is short, but references the pressure, case thickness, and headspace issues with rifles chambered for those different rounds.
@Dave17 has an article with the difference between the 7.62x51 and the .308, but the two we are talking about are closer than the .223/5.56 nato debate. Long story short is if you are marked nato on the barrel you are safe to shoot the .308 win in it as the nato round is a bit hotter. If your barrel was marked .308 and you were curious about the nato cartridge, depending on what you are shooting we might be having a different conversation, but since you are marked with the nato, go buy a box of .308 if you like and use in good health. Just be aware that as with any time you change ammo, don’t expect your sights to be zero’d.
Thanks to all. This helps a lot. I’m accustomed to having a 30/30 or 45 where they use one cartridge type not just about anything you can shove in it. I will have a Gun Smith take a look. This should answer several questions. Thanks again for the advise
Your welcome, we are all here to help each other.