.223/5.56 load development

[Paul]

I'm starting load development for my AR-15 and trying to find an accurate .223 recipe. I tested a few different powder charges last weekend with 55-grain bullets and got mixed results, some groups were decent, others were all over the place...what powders and bullet weights has anyone found most consistent in .223/5.56? I am looking for something reliable for both target shooting and occasional varmint hunting

 

[rfd]

For starters, what's the gun's rifling twist, bbl length, powder used, chambering, and what groups are you getting at what distances?

If you're running the gun as semi-auto, that will limit how the cartridge OAL can be set (jump from the freebore to the rifling lands) unless you single feed.

 

[Barry D. Thomas Sr.]

24.6 Vithi Vouri N140 under a Sierra 69 gr I use 1:7 Twist

 

[rfd]

I also use N140 as well as Varget, Hornady 68 and Berger 70 in my 1:7 AR15 builds (16" and 20"). The Bergers require single feed and are more accurate out to 500 yards than the shorter build Hornady 68s for semi-auto feed. For single feed I use a Kali Key BCG, and for semi-auto I use a brass catcher.

As with any load development do test out powder weights and cartridge OAL. The more precise we are the better the consistent results.

16" semi-auto ...

 

[mauser888]

Varget for me. 25 grains for the 55 grain FMJ.

 

[rfd]

...I tested a few different powder charges last weekend with 55-grain bullets and got mixed results, some groups were decent, others were all over the place...what powders and bullet weights has anyone found most consistent in .223/5.56? I am looking for something reliable for both target shooting and occasional varmint hunting

The 1:7 twist is best for bullets heavier than 55 grains, try 68 grains.

 

[Elixir]

Try H335 or Ramshot TAC for 55-grain bullets, they meter great in an AR. If your barrel is a faster twist, switch to 69-77 grain bullets with Varget or RL-15 for better accuracy

 

[Sky_walker]

You can also try 55 or 62 grain, log everything, and celebrate when the groups stop mocking you

 

[rfd]

For a 1:7 bbl twist I'd go no lower in bullet weight than 62 and thoroughly test for load development. For my 1:7 ARs, the 68 Hornady was the magic weight that still allowed a cartridge OAL that auto loaded well. The 70 Berger I'm also loading requires single feeding in an AR with a dedicated Kali Key BCG. I've tested Bergers to 80.5 grains and they're all good, but sticking with the 70 grain.