Re: 53gr V-max in 223
Hi 112Savage, i am using the 53 grn V-Max in my .223 AI and am loading an Australian powder called (Benchmark 1). It is roughly(if I can believe my comparison chart) equivalent to H322, faster than IMR 3031 and slower than IMR4198. I load 27 27.5 and 28 grains respectively over Rem 7.5 primers. My COAL is 2.400, accuracy is V good at better than .5 for all loads. Speeds over a F1 chrony were (approx) 3630fps, 3690 and 3740. I know these are getting to be pretty warm loads as I have some primer cratering but NOT flattened primers. The cratering could be caused by too large a firing pin hole in the bolt. I have measured my head diam just forward of the extractor groove and have no expansion there.
I am not familiar with IMR 8208 xbr so don't know how fast/ slow that powder is. It would seem that if your primers are not flattened or you have no cratered primers or split necks that you are within tolerances for your gun. I must add that these indicators are by no means concrete evidence of acceptable pressure but are usually pretty good in that regard. I forgot to add, my rifle is a Ruger VT with 26 inch barrel.
Good luck with your loads.
PS my original load was 30.0 grins of BM1 under a 40 Vmax for over 4025 fps and never had any pressure problems.