Any Trends in Alloy Hardness and Group Sizes???

My .38 Special loads with my own cast SWCs are okay enough, 2.5-2.8 inches at 50 yards, but the .45 SWCs are not consistently that good. Usually barely 3 inches, often 3.5.

I have some loads that are SAECO 5/Brinell 8-ish, but most recent pours have been an alloy that's SAECO 8/Brinell 14. Since these are NON-Magnum loads, I'm tempted to save the harder alloy and load Bullseye loads with the softer stuff. But since we've had such good accuracy with BHN 14 loads over the years in .357 and 9mm (even in .30 Carbine!), I hesitate to leave some proven success behind with what I usually smelt the batches to be.

Any reason to avoid a softer alloy? None of them lead to any appreciable degree, with either RCBS lub (stinky!) or a more summer-tolerant lube called TAC#1.

I have found that BHN of 15 gives me the best group size and as long as the bullet fit is correct, no leading.
Remember "fit is king".

Dave C.

I have never found any effect of alloy/hardness if fit is correct and there is no leading. For .38 spl and .45 Auto, I find 7-12BHN is all I need. Used to be 19.5 lbs WW and 0.5lbs 50/50 solder.
Found the mold design was much more critical than the alloy. RCBS 452-201-SWC is the best mold I found for my .45s, with the H&G #68 being second. Found 231/HP38, AA2, and Bullseye to be the best powders (in that order). Found as-cast and pan- or tumble-lubed beat sized bullets every day. Found having the shoulder in contact with the lede/rifling was the best.