Is this normal ?

[Sneakfoot]

Well I poured my first boolits the other day and after I got started I didn't want to stop. I learned its a matter of heat and timing. I think I made some good boolits,some may be a little frosted but I'm still gonna shoot them. I bought a Lyman mold, 50 cal. 395 gr. Great plains. The boolits are supposed to have a dia. of .508 but they are turning out closer to .506. Is that normal?

[geargnasher]

Frosty boolits in a muzzle loader? Frost usually means antimony and sufficient mould heat are both present. You know you're supposed to use pure lead for that, right? You might have a devil of a time getting that two-diameter boolit into the muzzle with a short-starter, and it probably won't swell much when fired. What alloy are you using here?

Unfortunately, Lyman has been consistently churning out moulds that cast a few thousandths undersized for the last several years. I think they have two moulds that are currently accurate and maybe even a little on the large side, one is a recent manufacture 429421 DC and I can't remember the other one, but I've been watching the reports roll in over and over and Lyman has not only been making them undersized, but often out of round. The concentricity issue is related to the cavities not lining up, like the blocks slid away from each other due to the torque of the cherry against the boring vise, so when mated they overlap by .002-5". I have quite a few examples myself of both of these recent-production phenomena.

Another issue with the undersized moulds is that with pure lead, boolits are even smaller than with alloyed lead, with Linotype and similar high-tin, high-antimony alloys casting the largest boolits. Hopefully this won't really matter with your front-stuffer, since the boolit relies on "bumping up" from the quick BP pressure rise when fired to seal the bore anyway.

For smokeless loads and antimonial alloys, don't worry about the "frost" at all unless the surface starts to look like broken cast iron or like it's been sandblasted. If you can wipe the frost off of a cooled boolit with a twist of a dry rag and the boolit is smooth and shiny underneath, then you're running the mould temperature right where I like it to be. Others prefer a cooler mould that drops shiny boolits, but it's more difficult for me to maintain the temp just right for shiny, so I go past the "frosted edges" point to a nice, even, satin frost and keep the mould temperature there. You may choose a different road.

Another thing with wheel-weight alloy, and I'm assuming you're using something like it or you wouldn't be experiencing frost, is that the frostier your boolits, the smaller they will be, up to about two thousandths with typical clip-on wheel weight alloy and .45 Caliber. I don't cast .50 so it might be a shade more compared to boolits run in a cooler mould (shiny finish).

Gear

[Sneakfoot]

I received the lead from a friend who was a plumber. He used it for weights on his duck decoys. Unfortunately he is gone now, but being a plumber I made the assumption (don't say it) it was pure lead. I can make a shiny boolit with a cooler mold, but they come out with small voids in them. Maybe I haven't found just the right temp. I was told that if I could scratch the lead with my fingernail it was pure.

[mooman76]

You can scratch even hard lead with a fingernail. Not really hard lead but like WWs. He may have mixed some WWs or other lead with pure just because ha had it so it may still be soft but enough other metals to frost abit. A small amount of other lead doesn't neccissarily hurt and may help with fillout.

[Sneakfoot]

Last night after reading Gear's post I found an old Hornady Great Plains Boolit and scratched it with my finger nail then scratched one that I made. There is a very big difference between the two. The Horandy boolit was much softer. So now I'll either have too trade what I have or buy pure lead.