Sure thing Curl.
; I collected spend trap wads at the local trap range, just to curb costs to nil - 'course, gas wasn't as expensive as it is now. I then cut the petals and compression system off with side cutters. This left me with the base cup-wads of plastic.
; For BP loads, it is necessary to isolate the plastic base wad from the powder charge as BP will melt the plastic onto the bore - something you don't want.
: I used slightly smaller than 14 bore balls at .684" diameter. A normal full choke is .690"(14 bore), ie: 40 points (.040") of choke off .730" = .690". A modified choke is about .710" in diameter, IMP mod about .700" etc.
: Now, the reason for the plastic base wads. Due to the cup and bore sized outside diameter(already fired and expanded, they hold the ball in the centre of the bore, regardless of it's size. (Cup up to hold the ball in the centre of the bore)
; In a cylinder bore, you could use a .730" ball from a custom J.Tanner mould. In a full choked barrel, so no damage would result to the choke, a ball diameter of .690" would work perfectly. Lyman and Lee both make .690" ball moulds. That ball, in pure lead, would weigh about 490gr. to 495gr. The undersized ball I used worked just fine, even in my non-choked bores, a tight .725" for each.
; To load - one card wad on the powder charge, starting with 3 drams, going upwards in 1/4 dram jumps. A dram is 27.3gr., so 3drams is 82gr. Over the card wad, is a cushion wad, then the plastic cup wad with the cup toward the shell top. Then the ball, then I used the cone crimp head of my old Press to press the plastic down onto the ball. The wad colunm is adjusted so the ball is almost comvered with the plastic of the shot-shell. I didn't try any in paper shells. I merely used AA hulls.
; I found room to work all the way up to the biggest BP laod used in 12 bore, 7 drams or 191gr. 1F powder. That one kicks like h$ll in a 7 pound gun, btw. I satisfied myself with 150gr. charges, which is 5-1/2 drams. This gave me 1,500 or 1,550fps, I can't remember exactly and was the moderate RB load for Africa. this one shot parallel in my gun, both barrels printing side by side all the way out to 100 yards. A 12" steel plate, 2-1/2" thick would dance and dance upon impacts with this load, laft/right/left/right time after time, offhand, whereas a fellow's 7mm mag with 175gr. bullets barely was able to cause the plate to swing gently back and forth a few times. After about 7 hits from the 12 bore, the holding chain broke. it sure impressed the bloke with the 7mm mag. He wante dto know the FPE, of course and wondered how the 12 bore could make it dance when his gun, producing much more fpe, barely made the plate move. As well, he had to shoot off the bench to hit it. I elected not to shoot off the bench unless I was testing loads.
; I then worked up a velocity duplication load using SR4756 powder. This was very easy, and had no more recoil (or presure) than a duck load - beautiful to shoot, but had the same power as the punishing BP load. BTW, the punishing BP load produces less breech pressure than the smokeless load.
: In summary - decap and re-prime - Black Powder 1F - 1/4" card wad, up to 2 fibre wads or more if room, plastic cup, cup upwards, ball, crimp pedals over ball.
: Decap and reprime - smokeless powder (Lyman's shotshell book has loads to try) card wad and fibre wad, plastic wad, cup up, ball, crimp.
: Adjust the wads to allow proper height for crimping the plastic over the ball. I found I could also do a normal folded crimp if rood allowed. This, I used mostly for smokeless loads, for ease of telling them apart from BP loads that only had the plastic folded partly over the ball. I hope this explains the procedure.
; Greener's book shows a cross-section of an 8 bore brass case loaded with a round ball. In it, the BP goes almost to the top of the case, leaving room for a card wad, and a cupped fibre wad, the 1/2 the ball sticking out the case mouth. With brass cases, this is how I would have loaded black powder. The "Old West Scrounger" and maybe Trackofthewolf.com has 12 bore brass cases for sale. The typical load for the 8 bore round ball loads, for both rifled and smoothbore guns was 8 to 12 drams.
; BTW- no damage to chokes, even with the .684 ball tightly patched in cotton as done by my friends for shooting moose while duck hunting from their full choked guns. I never got around to trying cloth patched balls, but don't see why they wouldn't provide even better accuracy than I got, due to their tight fit and foulintg softening traits. The boys reported 5" groups at 50 yards form their modern pump guns & holing both sides of a 45 (IMP) gallon drum wit WW round balls. Factory Foster slugs merely made lead splashes without indentation.