Hang Fire
06-21-2010, 01:53 AM
Common knowledge that military (and some civilian) rifle bore diameters can vary greatly for given calibers and getting the correct boolit mold and sizing for such bores requires more than just guess work. Know this has been addressed in various ways, but this what I came with up for making lead rounds when slugging bores.
I took a length of 3/4" x 1 1/4" aluminum bar and when I want to slug a bore, I just drill a hole through 3/4 side with the nearest fractional drill bit for desired caliber.
I then put some soft lead in a ladle, melt it with a propane torch and pour melt into drilled hole. (which is plugged on backside with paper or cloth) Knock lead round out, cut off sprue, with a soft hammer tap it flush with muzzle, then a few inches further down muzzle with correct size brass or aluminum drift and upset it as normal for bolt actions. With drift flush to muzzle, on a solid surface, I place muzzle down on a folded towel, insert an appropriate diameter brass or aluminum rod from receiver end. Judiciously using a hammer on rod, upset the lead round, insuring it conforms to fill the bore, remove the drift and then tap now sized round out muzzle.
If just want to check muzzle wear etc, tap the lead round flush with muzzle and upset as per above.
Recently acquired a M-38 6.5x55 Swedish Mauser and finally got around to slugging the bore. Drilled a 17/64" hole in aluminum bar for lead round, when slugged bore, was surprised to find the groove diameter is .2695". I have been complaining about a 6.5 Lee Cruise Missile mold throwing WW cast boolits at .271" and the difficulty of sizing down to .266". But now find it is near perfect size for this particular rifle, so feel rather stupid and to paraphrase the carpenter's adage, measure twice and cast once.
I took a length of 3/4" x 1 1/4" aluminum bar and when I want to slug a bore, I just drill a hole through 3/4 side with the nearest fractional drill bit for desired caliber.
I then put some soft lead in a ladle, melt it with a propane torch and pour melt into drilled hole. (which is plugged on backside with paper or cloth) Knock lead round out, cut off sprue, with a soft hammer tap it flush with muzzle, then a few inches further down muzzle with correct size brass or aluminum drift and upset it as normal for bolt actions. With drift flush to muzzle, on a solid surface, I place muzzle down on a folded towel, insert an appropriate diameter brass or aluminum rod from receiver end. Judiciously using a hammer on rod, upset the lead round, insuring it conforms to fill the bore, remove the drift and then tap now sized round out muzzle.
If just want to check muzzle wear etc, tap the lead round flush with muzzle and upset as per above.
Recently acquired a M-38 6.5x55 Swedish Mauser and finally got around to slugging the bore. Drilled a 17/64" hole in aluminum bar for lead round, when slugged bore, was surprised to find the groove diameter is .2695". I have been complaining about a 6.5 Lee Cruise Missile mold throwing WW cast boolits at .271" and the difficulty of sizing down to .266". But now find it is near perfect size for this particular rifle, so feel rather stupid and to paraphrase the carpenter's adage, measure twice and cast once.