Bought a Zastava M70 (Tokarev platform) 9mm that I was putting cast boolits through (Lee 124 grain round nose tumble lube).
They were keyholing something severe 9/10 times. Figured something was off with the mold so I put it aside and just shot cheap factory ammo through it until I got around to fixing it.
Fast forward to last week. I had several dozen boolits left that I didn't shoot up. I decided to try and experiment. I loaded up some sized and and left some as cast .5cc of Unique and CCI primers (same recipe as before I believe.)
My dad has a nice little Walther P1 and we took both out and ran both kinds of boolits through them.
Results: no keyholing out of either pistol with either variation.
Literally nothing changed. Same batch of bullets, same recipe, same barrel, just some fresh lube (Lee Alox) for good measure.
FWIW, as cast they were coming out about .360, sized .356-7 straight WW alloy.
Thoughts?