ingenious DIY 12 gauge slug mold

[sthwestvictoria]

I was given this mold in a box with some other commercial molds, mostly Lee from another local shooter. The provenance is unknown.
57990
As you can see from the pictures it is quite ingenious in the way it obtains the hollow base with pin. It is quite fiddly to use as you can imagine as you need to pre-heat the whole contraption, pour in the lead, knock off the spure, turn it over and pop off the metal strap holding the hollow base pin and the pull out the base pin.
I admire the construction, the use of a pair of donor pliers to provide the hinge and the way the person has solved how to centre the base pin with out the hinge attachment such as Lee use.
57991
57992

It weighs in at 35grams (1 1/5onces or 540grains).
diameter is .734 inch. I was not able to get the projectile into a case with the shot wad in place but only when there was no wad. The dummy round did then chamber and eject. I am not set up for 12gauge reloading - I imagine this would be a stout load!

[Willbird]

Looking at that my first thought is he knew what he wanted to do, and he made a way to do it. Second thought was spurred by seeing the slot in the plate that aligns the hollow base post pin (hard to think of a better name) wondering of the larger dia of the plug/pin is the same dia as the inside of the mold, allowing you to place it between the two blocks in the reverse direction and use it to align the bottom plate so it centers the pin ? This mold may have been for a black powder shotgun ??

[sthwestvictoria]

Black powder use sounds very likely. There is also this mold:
58050

Throwing a nose-pour 293grain hollow base .452 boolit, in the vernacular style of the 12 gauge one.

[runfiverun]

he most likely used a gas seal and felt/cork/cardboard wads to adjust the column height within the case.
a roll crimp onto the shoulder of the boolit would contain everything.

[longbow]

Way easier to make a cylindrical pushout mould. Much quicker to use as well. I have made some that produce a slug very similar to that one.

Yes, you cut the petals off a shotcup or build a wad column from gas seal and card or fiber wads.

Also, 0.734" is a little large for 12 ga. Typical bore diameters run 0.729" to 0.730" with some rifled barrels being 0.727"... in my experience anyway. I have read of both tighter and looser bores but have not seen one over 0.730". In any case, squeezing a full bore slug down from 0.734" to 0.729" makes me cringe some. That is a lot of lead to displace!

Longbow

[Willbird]

Way easier to make a cylindrical pushout mould. Much quicker to use as well. I have made some that produce a slug very similar to that one.

Yes, you cut the petals off a shotcup or build a wad column from gas seal and card or fiber wads.

Also, 0.734" is a little large for 12 ga. Typical bore diameters run 0.729" to 0.730" with some rifled barrels being 0.727"... in my experience anyway. I have read of both tighter and looser bores but have not seen one over 0.730". In any case, squeezing a full bore slug down from 0.734" to 0.729" makes me cringe some. That is a lot of lead to displace!

Longbow

I took a gander at the decimal equiv chart, .734 looks like it was drilled with a 47/64 drill, count on a few thou oversize which covers the shrink of the alloy, he may have had some kind of drive through sizer die that got lost in the mess they shoveled off the top of the guys bench ;-)....if you had to you could make one from a section of 12 gauge barrel pressed into something else ?? If the guy was using brass shells I'm told a 12 gauge brass shell takes 11 gauge wads, and he might have taken comfort that the slug fit in it nicely.

Bill