I have been casting and shooting cast boolits for a little over a year now and am still trying to figure them out. I've been reloading for the same amount of time. Been shooting for over 35 years and only recently gotten into competitive shooting where reloading makes sense.
My latest pistol is a Glock G35 in .40 S&W that I use for GSSF indoor matches. Prior to it, I started out with my 10mm G29 with the stock barrel, and then a Lone Wolf conversion barrel in .40 S&W. Tried cast in the LW barrel with poor results in accuracy.
I'm in the process of fine tuning my loads and discovered that the G35 prefers lighter bullets. Finally got under 2" at 25yds with a 155gr Speer plated and 4.9gr of Win 231.
I bought a Lee mold for the 145gr LSWC and cast up around 100 last night. They came out at an actual 142gr. Loaded up a few of those with 4.5gr of Unique and for the heck of it, did some with the Lee 175gr with the same charge.
Also loaded up some 155gr Berry's FN and 155gr Hornady XTPs using 4.9gr of 231.
Went to the range and it was 32 degrees, foggy, no wind, and miserable.
Shot the cast boolit loads first. Could not believe the results. The 175gr Lee load was a disaster; keyholing, not even hitting the target, and I think one ended up on another target! The 145gr load was much better and had acceptable groups, though I did have one FTE.
When shooting plated and jacketed bullets, I get occasional poor groups, but never the mysterious and disastrous results I frequently encounter with cast boolits.
No idea even where to begin trying to figure out the results with the 175gr loads...
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Lighter load didn't do too bad at all; even with one of the rounds from the 175gr load ending up on it...
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