.223R Bolt-gun Loads

[AR Shooter]

Sent many a round down-range with 223R gas-guns of various ilk, both SR & long-barreled F-class. Have recently started on a single-shot bolt-gun for F-T/R and am wondering how much additional powder (RE15 - my gas-gun load was 24.5gr) one can put behind an 80gr bullet (Berger VLD, A-Max or SMK) without getting into pressure problems? Have a hundred of each to develop a load with. Was planning to load a ladder-test with each, starting at 24.5gr going up 0.5gr at a time. 24" long 8" twist barrel. Any suggestions?
Thx.

 

[XTR]

What freebore?

Mine rifle uses Dave Kiff's ISSF 90VLD reamer with a 0.169FB. It works very well with the 80Amax. Can't speak to the other two bullets you mention.

I shoot the 80Amax jammed 10 over about 24.5 grains of H4895 out of a 28" barrel. I get about 2875FPS or so out of that load. The rifles performance in Oak Ridge last week not withstanding, it has been a very accurate load. Obviously, If you have a shorter freebore you will likely find your load below that number.


Note: I was quite disappointed in my 223 last weekend. It has shot laser tight in every mid range match I've ever take it to, but for a reason yet to be diagnosed both my 80 Amax and my 90 VLD loads were shooting tall at 600.

 

[jlow]

I think this would depend on your freebore. The longer the freebore, the longer you can seat the bullet, the more case volume you will end up, the more powder you can put in, and the more MV you can get without getting pressure signs. Unless you are jamming and that changes things.

 

[ab_bentley]

I think this would depend on your freebore. The longer the freebore, the longer you can seat the bullet, the more case volume you will end up, the more powder you can put in, and the more MV you can get without getting pressure signs. Unless you are jamming and that changes things.

With .165" FB and 75gr Amax I'm at 25.5gr of Varget@ 2995 fps.

Adam

 

[watercam]

With .165" FB and 75gr Amax I'm at 25.5gr of Varget@ 2995 fps.

Adam

My data mirrors Adam's above...

 

[AR Shooter]

Thanks to everyone for the info. Looks like my gas-gun loads are pretty close so won't take a huge amount of work to figure out. Do have a relatively short FB at 0.140".

 

[USMCDOC]

Well i have used 80's, but all those that i have shot were in gas guns, my experience with a bolt gun has been limited to the 75Amax and the Berger 90VLD, with the Amax, my working load was 24.0 grains of H-4895; with the 90 gr VLD, in the past, working loads have been 27.2 grs of 2KMR, 25 grs RL15 and currently, i am using 24.0 grs of H-4895. Depending on your freebore, your jam or jump, i would figure that a working load might be safely for you between 24.0 - 25.0 grs of powder.. with exception with 2KMR powder, to which your threshold may be a tad higher.

 

[Berger.Fan222]

OAL of 2.510" puts the 80 SMK about 0.010" into the lands in the 30" barrel. 23.0 grains of Varget gives 2850 fps. Went to 24.0 grains without pressure signs, but 23.0 grains was the sweet spot for accuracy.