What caliber would you like to see become mainstream in the AR-15?

I think 6.8 of the options you've listed for deer etc is the best overall for the platform but for those wanting to squeeze out really long range shots (and if you have a long enough barrel) the 6.5 would be ideal.

Great 6.8 FAQ here: http://demigodllc.com/~zak/firearms/6.8SPC/faq.php

Also the .243 / 6mm wildcats would be something to experiment with.

In the end though the military will most likely just return to using 7.62x51mm long before they'll adapt any of the above...IMO.

6.8 seems to fall far short of its expectations.

I'd have to say something along the lines of a WSSM, between 6mm and 7mm, capable of getting good velocity with a 100-120 grain hunting bullet from a standard-sized AR-15 that doesn't weigh too much.

The AR-10 is just too much gun to lug around, for calibers that fall on the low end of lightweight bolt action rounds, but the regular AR-15 platform can be the right size and weight for field use.

Otherwise, I don't really care. If it's going to be a toy, a serious paper-punching or gong-clanging gun, or in general a gun too heavy to grab for a hike up a mountain, .223/5.56 is a great caliber, or .308 in the AR-10. The only reason I'd want something else is for hunting.

6.8 would be an improvement I would like to see, JMO though.

I'd have to say something along the lines of a WSSM, between 6mm and 7mm, capable of getting good velocity with a 100-120 grain hunting bullet from a standard-sized AR-15 that doesn't weigh too much.

Click to expand...

I agree

All the other calibers listed are mainstream enough to only be a midwayusa order and credit card bill away. The WSSM's are still very elusive and are only available from a couple sources

7.62X25. I know some uppers have been made in this caliber. I would like to see more of them on the market so perhaps the prices can come down. For a small pistol cartridge, its a heck of a round.....and cheap.

for me the perfect caliber for the ar15 would be 308 as the mainstream caliber for the rifle..........

If the WSSM is rare because it doesn't work all that well, then something with similar case volume, but maybe some different tapers that are designed to feed and eject well in the AR, would be great.

If the WSSM is rare because it doesn't work all that well, then something with similar case volume, but maybe some different tapers that are designed to feed and eject well in the AR, would be great.

Click to expand...

That's not what I'm getting from the reports I read.

I'm taking away that the WSSM's feed better in the AR than any of the bolt guns they were originally intended for due to the straight shot into the chamber from being single stacked in the mag with no taper to jack with feeding.

Just look at what the cases designed for the AR have in common in little to no taper (Grendel , SPC, 450 .223 ect) But look at the 7.62x39 which actually doesn't work in the AR too well, lots of taper there.

No the reason there aren't more WSSM's is they require a completely non spec upper, bolt, bbl extension and nut. They are in simplistic terms an AR10 upper shorted to fit on an AR15 lower

44 mag.

I agree wow6599. So would I. Even on a limited basis.

The Grendel personally. I always had a soft spot for it and feel it's very under-utilized.

So long as you do your homework and get one with 1:11 or 1:12 twist with good rifling design and the correct chamber spec... 6.8 SPC II (or 6.8 x 43) the 6.8 perfoms quite nicely. SAAMI spec'd with the faster twist rates and rifling used with the .270 is where the 6.8 isn't able to shine.

Another vote for 7.62x25.

Surprised 7.62x51mm wasn't on the list, that's what I'd vote for.

Dionysusigma said:

Another vote for 7.62x25.

Click to expand...

lol

The caliber it should have been chambered for in the first place...6x45

I'd like to see the big bore thumpers become more mainstream. The .458 SOCOM, .450 Bushmaster and .50 Beowulf have the most big game utility out of all the calibers that fit the AR15 platform.

I hope 6.8 will become mainstream, my next upper build is going to be 6.8 and I would love to be able to go to any Wal-Mart and pick up a box of 6.8 for 10 bucks.

7mm-08 would get me to consider one.

William

7mm WSSM

10mm.

6.5 Grendel.

The performance is excellent. I'd love to shoot paper with it at 1,000 yards.

It may not be the do everything caliber, but it sure is versatile.

.351 Winchester?