(.308) vs. (7.62x51 NATO) Accuracy TEST in my AR-10

Shooting different brands and sizes of ammo through my AR-10 to check accuracy and reliability. I wanted to see if there was a difference in .308 Winchester ammo over the standard m80 ball (7.62x51 NATO). The results were about what I expected….

[@charlesludwig9173]

I shot the following in NRA long range competition through a Remington 700 which was fitted with a 24 inch 1/11 twist cut rifled bull barrel from HS Precision: M852, M118SB, M118LR, FGMM 168’s, and FGMM 175’s . The most accurate ammunition at the 600 yard line was 168 FGMM and M118LR but M118’s recoil wore me out. At the 1000 yard line M118LR was best and with all of this variety fired in the 600 and 1000 yard competitions I won the American High Power Rifleman Award in Long Range. Of course, the M852 and M118 rounds are 7.62 match cartridges for M14’s used in competition but they shot well from my bolt gun, thousands of them. So no problems from my experience, and most of this ammo except M118SB could get me into the half minute arena at 100 yards. Also, since all of the 175’s use an MOA wind constant of 10 at 1000 yards in head math was able to help me properly adjust for wind in short order, which was a major factor in my success with it all. BTW, when the .308 came out Western Cartridge produced factory loadings with bullet weights as I recall from 110 to 220 grains so not good for use in M1A’s that came on the scene in early 1970’s since these rifles like the M14 were tuned to shoot projectiles from 147 to 173/175 grains.

[@Philip_Corley]

good info

[@chrispike8879]

Less talking more shooting. Well informed on all the specs and fundamentals

[@Philip_Corley]

considering I just picked up a RCBS Rock Chucker and a bunch of reloading equipment, there will most likely be a ton of shooting content coming. thanks for watching

[@anthonybrown2426]

I have a POF Revolution DI 308 16.5” barrel. I’ve purchased many different manufacturers and grains of ammunition and found anything lighter than 150 grain is huge groups like 2-3 moa. Hornady Black 168 grain is 1/2-3/4 moa consistently. Federal Go;d medal match is also under moa five shot groups. The federal ammunition and Hornady is the majority of what I shoot. I’ve found Winchester ammunition in 308 and 556 is crap. Very inconsistent velocity which equates to large groups. Shorter barrel normally needs heavier grain to stabilize for good groups.

[@Philip_Corley]

Federal GMM ammo in both 168 and 175 grain shoot good in all my .308s. The Hornady Black 168 and 178 grain is really great ammo too. The heavy bullets shooting better in your gun could also have something to do with the throat of your chamber and the twist rate of your rifling.

[@jeffgenchi5863]

All modern manufacturers have confirmed we can run 308 in a 7.62 NATO. I have a new SIG 716i tread and several 308 builds. The brass has expanded the same. From my research the best argument for no 308 in 7.62 guns really affects older guns with lots of use. Full auto mill surp guns may have too loose of head spacing therefore causing a dangerous condition. I use a 308 go/no-go gauge and it is the same in either of my barrels. In reality if your gun is head spaced right you can shoot them all. I have reloaded 308 for years. No issues in either AR10. I agree find what works best in your gun. I build my own ammo so I can control the quality. Great video. Thanks for posting. Just thought I would share my experience in case it helps anyone. Because the manufacturers will tell you you can but not why. SIG was not helpful. Lol

[@Philip_Corley]

Really good comment, thanks for adding some good info. I appreciate you watching.

[@jeffgenchi5863]

@@Philip_Corley I really love them AR10 platform. Thanks for continuing to the platform.

[@bradwilliams1869]

What ammo runs good in your 716i? I can get m80 ball to close in under 3.5" inches. I'm wondering if I have a defective barrel

[@johnpoole8321]

Agreed, go the few extra bucks for the power shock for all around plinking and hunting.

[@Philip_Corley]

Hornady 150 grain american whitetail shoots just as good in my gun but I didn't have it handy for this test.

[@MikeSmith-pq4wz]

You get what you pay for as the old saying goes. My Armalite AR-10B, which costs 2K+ but will shoot 1inch groups or better at 100 yards using AAC match ammo. Maybe, you should try AAC ammo or upgrade the barrel to a match grade barrel. May I suggest a Ballistic Advantage 20" Heavy Profile barrel and have it fluted to reduce weight. You will be getting 1 MOA groups after a little upgrade! You can't beat that for only $250.00

[@Philip_Corley]

good quality match ammo and a good scope makes a big difference. still I wouldn't say i'm dissatisfied with the accuracy. the gun has produced several sub moa groups. not bad for a $700 AR I guess I could do a match grade ammo comparison video?

[@davefowler7146]

I appreciate the video but sometimes the quality of the barrel, bcg, can affect accuracy. Some rifles like my howa bolt are tack driven no matter what ammo she’s fed

[@Philip_Corley]

I've been impressed with this gun overall. It was not an expensive AR-10 and meant to be a truck gun but it's turned into a tack driver. I've bought parts from del-ton before because they make a lot of mil-spec stuff but this is my first complete gun built from all del-ton components.

[@Philip_Corley]

Thanks for watching! Hit the THUMBS UP👍 and make sure to SUBSCRIBE. As always, I appreciate your comments and feedback.

[@thesanfordmethod1905]

what's the barrel length on that beast?

[@Philip_Corley]

16 inch barrel but it's a heavy taper. The weight keeps recoil down a good amount

[@thesanfordmethod1905]

@@Philip_Corley Awesome, thanks.

[@dash8465]

All those hogs.. the bolt gun and a 5 pounder binary/Tannerite covered in corn would take out a whole bunch at once. Even the ones further away, internal bleeding would get more than you’d think.

[@Philip_Corley]

I have never tried tannerite but the thought has crossed my mind when they start eating all the corn before deer can get any. We will usually set a steel pen with a trap door to get more then one at a time.

[@michaelbarfield528]

I will be buying more Federal Fusion and Power Shok at Wally World.....😊

[@Philip_Corley]

I hope we don't live in the same town. LOL I keep an eye out for it too.

[@michaelbarfield528]

@@Philip_Corley I have four Wally World superstores within 50 miles of my home!!!!!! And their ammunition counter is well stocked for now.....😊

[@donaldatkinson7937]

Don't underestimate the killing power of fmj bullets, millions of people have been killed with them. Thousands of deer are killed each year with Sierra match king's. Few years ago I shot two deer within minutes of one another with a 357mag revolver with cast lead bullets that I cast, neither went a foot. In a shtf event, you'll be fine with fmj

[@Philip_Corley]

I agree. The matchking bullet is a thin jacket hollow point and very devistating on game animals. It expands and pieces of the copper jacket go everywhere inside the body cavity. Full metal jacket give more of a passthrough wound with deep penetration and good blood trails. I have shot a ton of stuff with the 175 grain .308 matchkings

[@mj2801]

Do not fire .308 Ammo on a rifle that is stamped 7.62x51. The Chamber pressures of this rifle you are using is designed for 7.62x51 not .308. The .308 Ammo will exert an additional 12,000 PSI on that chamber which could result in the warping of the chamber, and in some cases a catastrophic failure of the chamber wall casing injury to the user. On the other hand, a chamber stamped as .308 can fire both .308 ammo and 7.62x51 since it can handle to lower pressures of the 7.62x51. Don't let anyone try to sell you .308 Ammo on a Rifle that is chambered 7.62x51. There is no excuse for not being smart about this. This type of information can get people hurt thinking its ok to fire .308 on a rifle stamped as 7.62x51.

[@Philip_Corley]

Thank you for bringing up a good point. If you watched the entire video I made mention several times that I was aware of the differences and that I was firing these different ammos at my own risk. If you had taken your research a little further you would have also found beyond SAAMI specs that NATO measures pressure differently. When you convert chamber pressures and look at the velocity of some 7.62 ammo you'll find less than 200psi in commercial .308 vs Military 7.62 ammunition. I'm glad you're watching the video and giving your safety opinion but I encourage you to read more articles and do more research. I take the same approach when trying new ammo as I do when handloading ammunition by staying observant of any signs of pressure or stress to the ejected brass. The video purpose is to show what I do in my own personal rifle and not to tell anyone what to do with his or her own personal rifle.

[@mj2801]

@@Philip_Corley firing this ammo at your own risk does not make it better and may encourage other to do the same and may not as lucky, hurt themselves and others present. Not a good role model.

[@Philip_Corley]

I hope that everyone who watches this video will use their own judgement and stay safe.@@mj2801

[@Mike80528]

.308 Winchester and NATO use different standard for measuring pressures. You cannot directly compare the two. Look at the muzzle velocity of either with the same weight bullet. I am seeing rated velocities within manufacturing tolerances of each other telling me the functional pressure is equivalent because...physics.

[@dx-xb]

@@Mike80528 2000psi difference, if your rifle cannot handle that ( which normally are designed to handle 150% or more) than it will blow up either way

[@Youdoneedmyname]

Those groups are absolutely horrible.

[@Philip_Corley]

Well.... There's always room for improvement I guess. LOL