Why are you reinventing the wheel?

"Anemic"? I've seen four rifles chambered in 6.5 Grendel ping every piece of steel on my range. All with 130 gr bullets.

Never have I seen a 5.56mm in an AR platform do it. Even though we tried. Anemic applies to the 5.56mm, look at how many hog hunters left it for the 6.5 Grendel or the 6.8 SPC.

Yes, I understand we are the only ones following the "rules".

Well, since Uncle Sam won’t listen to me, it doesn’t matter if I at least suggest a rethink of the military round. Still, there has to be a better one that could be developed. The 6.5CM got developed, to fill a niche. The 6.5 Grendel is an acceptable round, but where does it rank compared to the 6.5 Carcano round. I don’t have my loading books with me, but I expect the Carcano round is better. So is that progress? The Grendel just fits the on-hand hardware (AR15), and is apparently an improvement over the 223 in that rifle design.

What I don’t know is whether or not the 6.5-30 RemAR can be used in the AR15 platform.

Just thinking out load (sorta).

1. It has to fit in the M-16

2. What your new cartridge do that the 6.5 Grendel cannot?

Neck up a 224 Valkyrie to 6mm and give it a 1:7 twist and call it the 6mm NATO. Shoot 95-105 high BC OTMs.

The 30 Rem AR will push a 130 gr bullet to 2800, which is 400 or more FPS faster than the Grendel and the Soviet era case the Grendel is based on. Neck that 30 AR to 6.5, and you’d have a serious cartridge right there with the 260 or 6.5CM, with the same steel banging capabilities.

I don’t know if it would be workable in the AR15 platform. the case head is not small.

Case length, plus bullet length, is the big question.

The R15 is a proprietary rifle with the 30AR cartridge, it is not mill spec so it would be full replacement not say BCG, Barrel and Mag like the Grendel would be for he existing M4 or M16 arms.

Interesting about the 30AR which is a neat cartridge for sure but the overall case length and bullet ogive lengths do not really play into being able to use high BC bullets for the range 400 to 600 yards to extend the useful range of the infantryman. With teh Grendel you have a very comparable trajectory out to 400 yards then a little better with more energy from 400 to 600 or more yards than with the 30AR. The one

30AR link

In Remington fashion the velocities given are from a 24 inch barrel even though the R15 has a 22 inch barrel. BC of the 125gr bullets is given as .267 and a 123gr Hornady 6.5 bullet has a realistic BC of .490.

No doubt the 30AR is a fine hunting round at ranges most of us should be shooting but if carrying one or the other in the Military I will take the Grendel. More rounds in a mag, better ballistics at distance where the 223 is said to be ineffective (though I do not want to be hit with a bullet from one at any distance).

Dig into bill Alexanders information about the Grendel it presented several challenges bullet length for the round to have a somewhat high BC but still fit in the magazine. The Grendel I think has more in common with the PPC line of cartridges than the 7.62X39. It is basically the 6mmPPC with the shoulder pushed forward a little for more case capacity and necked up to 6.5mm. Interesting that lapua had some voice in that choice and made the first brass for teh 6.5 Grendel. Easy for them to do since they also make 220 russian brass which many shooters used to get their PPC brass.

For the record, I was suggesting necking the 30AR to 6.5, therefore the same bullet in competing calibers.

Also note that case length of Grendel and 30AR are the same (0.01 diff) and COAL are the same. 30AR case head is bigger.

As for having to change or modify the M16 platform itself, that will happen eventually anyway. Why wait? It isn’t like the M16/M4 is perfect. It’s just what we have at present.

Maybe it’s just me, but I can’t see what’s special about a round that pushes a 130 gr bullet to 2400 FPS. Surely there’s a better option, and I’m just using the idea of a necked down 30AR as one option.

I thought the military solved this already with their new M855A1 bullet. Supposed to be lethal to 600 yards.


https://usarmorment.com/pdf/M855A1.pdf

I wouldn't say "solved", more like a stop gap measure.

I read all I could find on the M855A1 some time back. Supposedly it is pretty rough on the M4s and reduces reliability somewhat. At that time I tried to find out what pressure it's loaded to, and one data sheet or article listed it as CLASSIFIED.

I'd bet on it being dropped at some point.

I can't see how it's not going to be harsh. Longer bullet seated deeper and going faster than previous green tip ammo.

They should have just adopted the MK318 Mod 0 that the Marines originally adopted which was a simple design that solved all the problems.

I'm not ready to buy into the figure given in this article until I see a US military document, but it could be correct. If so, then things have changed dramatically. The article gives insight to dealing with pressure and gas problems.

http://www.gunsandammo.com/rifles/surefire-optimized-bolt-carrier-assembly/

River rider, that was interesting reading. When I started this discussion, which is about the same as plenty of previous discussions, my main interest was in what you knowledgeable fellows thought would be a good replacement round for the AR. It seems obvious that even Uncle Sam thinks the 223 round isn’t ‘enough gun’. Combine that with the likelihood that caseless ammo isn’t something for this lifetime, what will be the next move. Rather than totally replacing the rifle platform, changing the cartridge seems more likely. And that’s why I suggested the 30AR necked to 6.5mm. But the real answer is probably going to be a cartridge that doesn’t presently exist. Something designed from scratch to fit the platform and the magazines, with a bullet weight of 100 to 120 grains and a mv of about 2800 FPS. Probably 24 or 25 caliber.

I agree...it seems obvious that the military is not satisfied with the 5.56 round. On the other hand, I think the 6.5 Grendel has a lot to offer. I'm not really sure though, because we shooters don't usually mess with FMJs in the Grendel. I know there are objections to sporting bullets in military application, but I still think something like a 110-grain LRAB would be formidable.

123 SMK, G-1 .510 in a 6.5 Grendel. The military has been launching SMKs down range for decades. This is just another one.

https://www.sierrabullets.com/store/product.cfm/sn/1727/264-dia-65mm-123-gr-HPBT

This was one of the more interesting threads. I like when you guys nerd out on a topics similar to this.

It's all for fun, the military will not change from the 5.56 or 7.62x51. All the money is going to the Space Force.

The Space Force will shoot .45-70s. BC won't matter where they're gonna be.

Very true. It will take long range shooting to a whole new level.

Well, I hear you guys on the Grendel, but I still don’t consider it the answer for 223 replacement. The biggest thing going for it is that it fits in the existing platform. But, 2400 FPS mv isn’t good enough.

Maybe it would be best to just issue the newer lighter AR10’s, or revamp the AR15 platform to handle a serious cartridge smaller than the 6.5 CM and larger than the 223. And that’s what got me to thinking about something like the 30AR necked down to 24 or 25 caliber and a 100 gr bullet. Now that sounds reasonable to me. MV should be 2800+.

The 30AR case is the same size as the Grendel case. If you like the Grendel, why can’t we like the necked down 30AR?

Actually, the military has already started to make the change from 7.62 as mentioned earlier in this thread. Moving to 6.5CM