I just love these bullets.
I used the Lyman 51’st Edition / Sierra 124 JHP for my starting loads. In that I am using Winchester 244 somewhat complicated the process because it is such a new powder not much is published. I am using W244 simply because it is available in my area and nothing else like W231 or Unique is.
Bottom line -> I used my Chronograph (Competition Electronics) to zero in on a velocity of approximately 1150 fps. I am using Sterling brass (once to three times reloaded), RCBS carbide dies, CCI small pistol primers and 4.8 grains of W244 with an COAL of 1.08 in. I do not impart any significant crimp on the finished bullet – just a very light taper crimp as provided by the die.
Shooting these out of my M&P with a 4.25 in barrel, 1:10 twist I achieve a very consistent mean velocity of 1128 fps with a standard deviations
ranging from 7 to 10 fps.
Again – this is using STERLING brass. I feel that this brass is a lot stronger than say Blazer or other similar “soft brass” cartridges. If I switch brass I will have to adjust my powder drop. Softer brass with require more powder due to loss of crimp strength.
One thing that I have noted is that as I push the bullets to higher and higher velocities, the standard deviation in velocity goes to hell. For myself and my firearms (M&P / Dagger) – the above velocity is my sweet spot.
