Due to some mail I've received, I've decided to re-print some of the loads suggested in a book I have. These loads are actually higher in powder charge than what I used, but not by much. Different wad columns and weights of wads causes increased pressure. Much depends on what wad column a person is using.
: Combinations of wad columns can also be used, but always start low and proceed cautiously.
: I suggest, if you use an undersized ball and if it's properly loaded, it will never touch the barrel's walls and therefore, won't lead. I will remain spherical for better accuracy and will not have flat spots that promotes spining in fight. For such a ball, you could use a AA-type wad, petals cut off, with just the base of another similar wad, sitting on top, cup-up cradling the ball. This will hold the ball in the centre of the bore and help accurate shooting.
: If one uses a plastic wad or any plastic seal, cup down on the powder, start low with the powder charges. If you change any component, start low first. Changing any component can and will change the pressure produced. Be smart, start low.
; Roll crimpers are available from Lyman - use a drill press. Everyone has one of those, eh.
; Fold crimps develope more pressure than roll crimps as they are more difficult to open and pressure has to build more to open them.
: Note that in a choked gun, you MUST use a ball no larger than the smallest diamter of the bore or it might peen out the choke or split the muzzle. This is why Lyman used only u to .690" balls as that is the nominal size of a 12 bore full choke. Extra full is probably even tighter - I wouldn't even shoot balls through one of those.

;#1/. - Fed Plastic Hunting hull - - Win 209 primer 33.5gr. 4756,- BPGS, 1/2" fiber wad - BRENNEKE slug FOLDED crimp - 1,457fps at only 9,800LUP. That's a powerful load. I would start testing at 28.0gr. and go up slowly, chronographing and recording the results as to placement on paper and group sizes.
;2/. - same basic load with a roll crimp, but 36.0gr. 4756 - 1,508fps. 10,500LUP
;#3/. - Fed Plastic Hunting Hull - WW 209 primer - 33.0 gr. Unique Remington #R12L - 2, 20 ga. Butler 1/8" card wads inside,-.662" round ball (16 bore ball about 440gr.)ROLL Crimp - 1,531fps. 8,800LUP
;#4/. - Fed Plastic Hunting Hull - - WW209 - 30.0gr. Unique - Fed #12S4 - 2, 20 bore 1/8" cards inside wad, .662" ball fold crimp -9,900LUP
: #5 - Fed Plastic Hunting Hull - WW209 - 40.0gr. 4756 - Win WAA12 petals removed, - 1/2" fibre wad, - .125" card wad - .690" ball Fold crimp - 1,538fps - ROLL Crimp - 10,200LUP. Note the big powder charge - reduce to 30.0gr. if using a second base wad cup for ball guidance. a .690" ball will rattle down a .730" bore and be innaccurate with this load. They are counting on a choke to straighten out the ball.
: #6- same wads as #5, but FOLD crimp 'same' pressure with 1,456fps and 36.0gr. 4756.
: #7 - WW Comp/formed Hull- WW209 - 37.0gr. 4756 - WAA12 petals removed - 2, .125 cards, .690" ball, ROLL crimp - 1,534fps, 10,400 LUP
; #7 - same hull, primer 32.5gr. 4756 -same wads, FOLD crimp, 1,428fps, 10,100LUP. Note very minor pressure drop and 106 fps lower velocity. The only diference in the laoding is the crimp. Now, you may be able to load up to 33, 34 or 35gr.with the folded crimp and gain back the lost velocity with only a bit increased pressure but maybe not. Your gun will tell you, if you speak the langage.
; The maximun allowable pressure is the same as a modern 3 dram, 1-1/8oz. trap load, or 3-1/2" 2 oz. goose load or 2 3/4" 1-1/4 oz. field load - they all develope the same pressure and thus your handloads too should be held below 11,500LUP which is normal maximum pressure of all shotshells and to what they are all loaded by factories
: Depending on hull used, wad column used, projectile and crimp form, the powder charges with 4756 ranged from a low of 27.0gr. to a high of 42.0gr., and pretty much producing idential pressure with the same projectiles. The only differnce was the hull and sometimes the primer. So - one must be careful and ALWAYS start low.
; I suggest using this data for an 'idea' of what your 12 bore is capable of.
: When I started shooting balls from my 12 double, I started with known, low pressure, fairly low velocity, loads form a shotshell book using 1-1/4 ounce shot loads with 7625 and 4756 powder, but with the much lighter .684" round balls. This was a safe place to start and I reommend everyone similarly as well, unless you DUPLICATE the loads noted, exactly, with no deviation whatsoever.
; Today, if starting out anew, I'd get a .690" round ball mould from Lyman or Lee, probably Lyman and iron blocks rule. If a 1 ounce ball suits you as all you want it for is deer or black bear, buy a .662" mould and you can use wads without cutting off the petals, just by putting filler cards inside to take up space - that is all wads do - take up space and seal gas pressure behind. The petals will pretty much centre the ball in the bore.
: Hope this helps. You really all should buy the Lyman #2 shotshell book if it is still available, if not the #3 or #4, or whatever. I expect the newest one has ball and slug data too. If not, and if you have no shotshell handloading books, you need one for a place to start - as I did, using shot data, so buy the book anyway.