A couple of puzzlements.

Just for my general interest, experience and in no doubt, a vain attempt to ward off ossification and demise of the last few “ gray cells” I have remaining, I am loading Lee Drive Key, 1 ounce slugs, but being “ a Bear of very little Brain” (ABOVLB) I have arrived at a couple of “puzzlements” upon which I seek advice. Can you please assist?


My information resources are:
A... “The Lee Slug Mold” ( I do wish the Americans could spell) which contains recommended loading specifications.

A link https://tinyurl.com/mvjx35ff

and

B...The ADI powder comparison with other powders. A link https://tinyurl.com/yakd2h7h

The only two Lee recommendations, three counting comparable powders, with which I am able to comply with are the Winchester WAA wad and of the course the Lee slug.


“Puzzlements” start with the appropriate powder to use, which, with problems of which I am sure you are painfully aware, require me to use ADI AP70N as the “ADI powder comparison” states that it, give or take 5%, is comparable with two of the powders recommended for use in the Lee recommendations. Those being.


Accurate Arms # 5


Hogdon Universal.


Puzzlement # 1. Powder load
I am aware that the powder options are based upon variables such as hull type and primer, but I remain puzzled by the 13 grain variation between the four “recommended” maximum powder loads.


Accurate Arms, three recommendations start at 38.5 grain and moves though 40 grain to 41.5 grain but Hogdon’s is 28 grains.

Being of the cautious variety and ABOVLB, my intention is to commence my little play with the lowest, Hogdon’s 28 grain load even ‘tho it is a maximum, but I would appreciate your views which may assist me to understand this 13 grain variation of “Maximum.


Puzzlement # 2. Choke size.
Again, being of the cautious variety and ABOVLB, I have done my reading and for the slugs will use a choke size selected just to protect the choke thread inside the end of my bang stick, i.e “true cylinder”...no compression of pellets, ‘cos there is just one big one and I am using the recommended “Winchester WAA wad” to accompany it on some of it’s passage.


My “puzzlement” arises as I don’t know if any of you have ever removed a choked 12 g barrel and pushed a sabot load, which this Lee slug is in case you have not yet ” clicked” onto that, through it from chamber to choke exit but when I did this the recommended slug in the recommended wad was a happy chappy until it hit the choke exit......... and then it didn’t want to exit. The” Lee Slug Mold” is silent on the pressure of the powder load required to force the “recommended wad containing the recommended slug” through a True Cylinder choke.


So, as I have no others to ask, is this resistance to be expected?


My thanks if you have stayed the mile with me to this point.

Attachment 168032

Puzzlement #2:

Is your barrel back bored so the bore is slightly oversized, so the choke, while cylinder, is tighter than than the rest of the barrel?

"Trespassers Will" suggests: A vernier caliper is your friend. Nominal 12 gauge bore size is .73 inches and a cylinder choke should be the same manufacturing tolerances may add or subtract a thou or so. An over bore barrel as already mentioned is a possibility but the choke should be the correct size.
Measure your cast slug, measure your choke, measure the wad at gas cup and shot cup, push a wad without slug through the bore and note any resistance.
The old "rule of thumb" was round balls and solids were 1 gauge smaller than the bore this ensured they would get out of even a full choke without embarrassment.
As yours are sitting in a slightly greasy and compressable plastic cup I doubt there will be any problem.

Puzzlement # 1. Powder load. I would say any recomended 1oz of shot powder charge should be ok for slug load. You may be able to go to a slighty faster powder as your not exactly going to blow your pattern ( pressure limiting).

Puzzlement # 2. Choke size. I have cut off the petals on the wad when making slugs. They are pretty irelevant when not using shot.

OK fron lyman manual5th edition
525grn lyman slug so more than 1 1/8th oz
universal 29grns
win 209
federal gold medal hull
wad WAA12F114
1400fps 10400psi

aslo federal plastic case paper basewad
31.5 grns universal
win 209
WAA12F114
1460 fps 10,700psi


remington plasic basewad case 525 grn lyman SABOT SLUG
universal 29grn
rem209P
WAA12F114
1392 fps 10,400psi


and paydirt finnally

winchester HS OR compression formed plastic case
525grn lymannsabot slug
universal 27grns
win209
WAA12F114
1364fps 10800psi


so do your research..those weight of slugs APPEAR to be heavier than what you using..SO ASSUMABLY your slug being ONLY different component pressure would be less.
hope that helps.