[serf 'rett]

..nope, one of the powders I use is W-231, which is a fast burning powder like Titegroup. A fellow gave me about three pounds of W231 which was likely over 25 years old. When I tested the old W231 powder, I used R-P brass, Wolf SP primers and the Berry’s 124 grain HBFP bullet. The range I tested was 3.2 to 4.2 grains, in 0.2 grain steps. My most accurate load was at 3.6 grains. I also used the same bullet for another test with new W231 powder, R-P brass and CCI500 primers. The best group for that test was at 4.0 grains W231. Same brass, same bullet, same COAL, same 3.2 to 4.2 grain charge range, but new powder and different primer, yet different charge weights produced the best groups.

The point is simple. If you are into making custom rounds for your firearm, you may need to do more testing and tinkering to find the brass, primer, powder, length, etc., etc. which is the most accurate in your pistol(s). Shoot the targets at a set distance using a bench and supports as needed to provide a stable platform, and then compare the results. I found it very interesting to watch groups open and close with small changes in charges or components.