"The special lube process used by Cast Performance produces a clear, dry lube, which is barely noticeable on the bullets.", and they aren't kidding. I can't see any lube to speak of in the grooves at all, the bullets just have a faintly slippery feel to them, unlike raw lead.
Going to try some as they come at .378" in this High Wall's .3751" bore, they should be fine, but I might also try to squeeze a few down to .377 and at the same time fill the grooves with some LBT Blue. It ain't cast shooting unless there's smoke..
Standard Lee, RCBS or Lyman molds for the .38-55 tend to throw bullets in the .378-.380" range. Those will certainly work in a .375" bore but IME about .001" over groove diameter is where you want to be in a rifle. With a good fit to the bore and #2 alloy I'm thinking 1600-1700 fps or more is doable with plain base bullets without leading. However, trying to size down 15 BHN bullets .002 or more from as cast diameter gets to be detrimental.
Guess I'll bite the bullet (no pun intended) and order some straight from the source sized to .376". Have to get a minimum of 250 for custom sizing, though.
Once I get an idea of how fast a plain base can go I can order an Accurate mold in a suitable design to throw bullets right at .376 or .377 with my #2 alloy, then start cranking out some good steel ringing loads.
Hawk is steering you in the right direction.
If my bore was .375, I would want to run a bullet diameter around .378 at least for good results and larger might be better. I don't agree with the .001 over bore crowd, especially with larger bores.
Sizing a bullet down .002 is absolutely no problem in the Lee push through kit, but I would recommend to try just loading and shooting those as is. The lube they use is a clear coating and should be fine. It should be tough enough that the lead will never actually touch the rifling if the batch is cured properly.
Trying to run them too small is where you will run into problems with leading.
