Ar-15 Loading Question

[cmb3366]

I recently purchased a DPMS LoPro Ar-15 and am starting to load for it. I've reloaded for bolt rifles for years, but this is my first gas gun. Do I need to crimp my loads? I bought a box of 60grFBHP Sierras (no-cannelure), not thinking that I might need to crimp. Another question, What are some good 60gr loads?, I'm trying Varget, H335, H4895; any others I am overlooking that usually yield good results?. Thanks in advance.

 

[Bullet]

I don’t crimp for my AR unless there is a cannelure on the bullet.
What twist is your barrel?
There are much better bullets for accuracy – Sierra Matchkings.

 

[dakotasin]

i never crimp any rifle, and that includes my ar's.

good 60 grain load: h-322, aa2230; varget works, though you'll probably be pretty heavily compressed.

 

[rbernie]

I crimp almost everything that I load using a Lee factory crimp die. If there's a cannelure, I use a pretty solid crimp; if there's no cannelure, then I use a lighter crimp.

For example, I'm currently working up a 223 load for a 20" 1:8" AR-15 using Hornady 75gr OTM bullets over Reloader 15. For this combination, if I skip the light crimping step, I'm rewarded with moderate amounts of vertical stringing. Applying the crimp brings everything back to normal.....

 

[YellowLab]

ONLY TAPER CRIMP DIES NEED A BULLET RING.

The Lee Factory Crimp Die uses a collet to squeeze the neck around the bullet.

Taper crimps take a lot of work.. trim brass, correct bullet.

Lee FCD work with varying length brass and any bullet.

For $8 its a deal... plus for magazine fed rounds you risk a setback bullet if neck tension if not correct.

If your press has a station for it, your ammo can only get better with a Lee FCD.

 

[stiles]

ONLY TAPER CRIMP DIES NEED A BULLET RING.

That should read roll crimp requires a cannelure, a tapper crimp does not.

Two companies make tapper crimp dies for 223, Dillon and Redding.

 

[YellowLab]

I stand corrected! Thanks!

 

[Cherokee]

I lightly taper crimp with Dillon die only to make sure there is no flare on the mouth of the case.

 

[redneck2]

50 or 55 grain bullet (I use Nosler BT's) WW cases, Fed match primer, 26.0 Varget, max mag length

We just shot 2 consecutive 3 shot 3/4" groups at 268 yards this week end with this load. Bushmaster Varminter 24" fluted with 6.5x20 Leupold

For whatever reason, Varget seems to consistently give exceptional results

 

[Grump]

Lake City and other USGI brass all trimmed, WSR Primers, cheap and ugly Winchester bulk 55-gr FMJBTs, Lee FCD, all from a 1:7-twist Colt "Match":

27.0 Varget, real nice, compressed not that bad, shoots 3 MOA, sometimes 2 MOA, all on 5-round, not 3-round cheater groups.

28.3 WCC 844, still airspace in the case, shoots 3 MOA, might do 2 MOA but I'm not bothering to check.

4064: was not yet up to max charge, and there was only 1mm of airspace at the TOP of the neck. Velocities were only about 3050 fps, IIRC. Accuracy was maybe half an inch better than Varget. Pain to load, powder wants to spill all over.

Change to Speer 52-gr HP flatbase varmint bullets and the 27.0 Varget load: 1.5 MOA all day long, no crimp, the AR feeds them just fine and does not set them back a bit. It's all in the feed ramp/magazine interface. A proper rifle will do fine. Remember, the M1 Garand will feed an empty case. The AR won't, but it's still okay b/c its feed ramp is more of a tip UP than a smash-back on the bullet.

IOW, I crimp only to fill in the cannelure, if the bullet has one.

BTW, no crimp on 69-gr SMKs, and they shoot no better than the varmint bullets...with a scope...off sandbags..

 

[ocabj]

CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.

I just settled on a MK262 Mod 1 duplication recipe in my 18" SPR upper.

25.3gr Hodgdon Varget
77gr Sierra MatchKing BTHP (.224)
Lake City brass (tested with 02, 03, and 04 headstamps)
Winchester SR primers

5-shot average = 2787.8 fps
15-shot average = 2796.6 fps

This load is definitely over all known published commercial data for the 77gr SMK and Hodgdon Varget in .223 Remington. This load is, in all likelihood, over SAAMI pressure for .223 Remington.

Only recommended for use in 5.56 NATO (or .223 Wylde) chambered AR-15 variants.