ELD 88 grain in 223/5.56 semi
- Thread starter caporal
- Start date
You are going to be pushing your luck.
Your chamber is so short that your seating depth will remove too much of your powder capacity to get enough speed to stabilize in the 1:7.
I run that bullet in my long throat bolt gun with an OAL of 2.640" but you will be under 2.3" I'll bet.
I get 2900 FPS easy and that provides the stability at 1:7. Even so, some F Class guys prefer just a bit faster spin rate.
I also have a 26" barrel, so that helps get the speed up.
You can try it if you want, but I would not expect much.
From a mag length 20" AR I would not go heavier than 77 grain SMKs or TMKs.
Back in the 80s when that rifle was released I had the Colt AR15 A2 Delta HBAR, so I have some experience with the rifle, although that long ago. I ran 69 grain SMKs with win 748 Ball Powder almost exclusively and they were amazing on deer and ground hogs with that fast twist. Back then when the world was still sane, I could actually hunt with it and use 30 round mags. I wish I could go back to that.
Your chamber is so short that your seating depth will remove too much of your powder capacity to get enough speed to stabilize in the 1:7.
I run that bullet in my long throat bolt gun with an OAL of 2.640" but you will be under 2.3" I'll bet.
I get 2900 FPS easy and that provides the stability at 1:7. Even so, some F Class guys prefer just a bit faster spin rate.
I also have a 26" barrel, so that helps get the speed up.
You can try it if you want, but I would not expect much.
From a mag length 20" AR I would not go heavier than 77 grain SMKs or TMKs.
Back in the 80s when that rifle was released I had the Colt AR15 A2 Delta HBAR, so I have some experience with the rifle, although that long ago. I ran 69 grain SMKs with win 748 Ball Powder almost exclusively and they were amazing on deer and ground hogs with that fast twist. Back then when the world was still sane, I could actually hunt with it and use 30 round mags. I wish I could go back to that.
Last edited:
Munkey1973
CGN frequent flyer
- Location
- Regina, SK
^^^ Some very sound advice right there ^^^
Based on your intended application, from the Hornady line, the heaviest bullet I would go with would be their 75 HPBT (the 75 A-max is a bit longer -longer than mag length I believe).
Interesting thread... I am just about to process a batch of 1,000 once fired brass (fire formed to my MS with a very good 20" 1:7 barrel from ATRS).
I got a smoking deal on some 77 matchkings some time ago ... with about 1,350 projectiles.
I think 77 MKs might be a bit "iffy" but hoping to develop an accurate load for it.
Going to 3 different powders over 350 projectiles.... if there is no immediate sign of potentially decent groups, then I can at least sell 2 unopen boxes -at today's prices -and try going with a bullet in the 60 grain range.
I have heard tale that the "Camp Perry" competition shooters in the States, I forget what the game is called, that use AR15s at long distances for precise shots, single load their AR15s. This allows them to run longer bullets and COAL.
I've heard similar.
I don't have any firsthand experience with the particular bullet or platform, but wouldn't there be some risk of jamming the bullet further back into the case than seated depth as the bolt closes, even while feeding singles? I've read for example that with the Bergers, they group better when they're not jumping the lands but rather seated to just touch the rifling, so on top of potential pressure issues from having the bullet driven deeper in the case mouth, you might lose out on best groups as well.
Indeed in a normal chambering you might hit the leade and set back the bullet. Tough to say, most 223 chambers in my experience are pretty generous in the leade to keep pressure low. For instance my Ruger Precision Rifle in 556 and Savage Elite Precision 110 in 223Rem both didn't jam a 80gr ELDM until about 2.390" COAL, so quite a lot longer than AR mag length and 223 specification CBTO. But to really properly run the 80gr and 88gr ELDM and other 80-100gr tipped bullets, using depth of bullet in case neck to ideal location, you'd want like a 2.600-2.700" COAL as mentioned above by Maple.
So I guess what I'm saying is, if you seat the bullet like a 6.5CM or a 6mmBR, with base of bullet at about the shoulder-neck junction, you'll end up very long COAL, and probably too long for your chamber. So do the Eric Cortina method (or other) to determine your jam CBTO and COAL, and load a bit shorter than that, and single feed to your heart's content. Bonus points if you have a gunsmith run a throat reamer in your barrel so you can run them at 2.650" COAL and really maximize the ballistics out of that 223 barrel and semiauto receiver.
