I have a very old [made in 1897] (new to me) 38-55.  I slugged the barrel with some dential compound they use in the gage lab here at work and found the diameter to be 0.380, using their "vision system".  Should I order 0.377, 0.379 or 0.380 diameter cast bulelts?  I want to test some before I order a Brooks or Jones mold.  This my first "old" gun, the rest of mine are "new" old style guns!  Thanks for help. Tim K

Timk,

  I'll second what 40_Rod says. IMO, and what I do is to always size bullets .001" - .002" over groove diam. My original barrel is also .380" and I use a .381" sized bullet.

  But...... With that large a bullet you might not be able to chamber a loaded round. If at all possible try and find a bullet of the correct size and see if you can chamber it.

  If it doesn't chamber then you will have to either have the chamber opened up, or just shoot bullets sized to a diam. that will work. With BP an undersized bullet will bump up, but even at that use the biggest bullet you can chamber up to a diam. of .381" - .382". The other alternative, of course, is to breech seat. In that way there's no problem. This last is what I do with my gun since I only use it for Schuetzen shooting.

  You haven't told us what you plan on using this gun for so hopefully the above covers any contingency.

PETE

ah-ha timk,

a lever action is a horse of another color.. now we are talking fixed ammo that  must slide rite into the chamber with no resistance at all.

now if you want it for hunting plinking and lever action matches. for hunting and the tube magizine, you will need a flat nose bullet at around 200grs. for plinking, the 200gr bullet is a little heavybut, it's a good compromise. for lever action target and shilouette matches, 200gr is about rite.

so, i would think, no custom mold is necessary. lyman or rcbs should be able to fill your needs nicly.