It's been awhile since I posted here. Has anyone worked with this ctg. before? Full length .30-40 Krag case, necked to .25 & fire-formed with minimum body taper & 40* shoulder.

I have, and i love the cartridge. Mine's in an original, set tripper 1885 Winchester.

That's what i was looking for in the post below your's. It's the 250 Helldiver.

P

Highwall...How do you form cases prior to fire-forming? RCBS/Huntington catalog has no information..Midway sells a couple of forming dies..one is $99.00, the other is $130.00..but there are only 1 in each set..no explanation in difference..also they sell a base-forming die..I wasn't aware Ackley ctg. needed this one. I do have a 7X57 bushing type neck sizer..wondering if I can just run case in this die & finish forming in the full length .25 Ack. Improved die? Thanks for any opinions.

Its been several years since i formed my cases, but as i remember, i just necked them down. I have my fireforming load written down.

Well the RCBS .25 Ack. Krag Improved 2 die form set arrived from Midway & I ran a couple of new Win. .30-40 Krag cases thru. The instructions said to full-length size case after running thru #2 form die. I tried this and the new shoulder formed from sizing to .25 was left with a very narrow edge. The #2 form die left a more rounded shoulder. I am afraid of setting up a stress point in this area by full length sizing. Forming in #2 form die only leaves case contacting chamber shoulder and gives a slight friction drag when action closes. I think I will try fire-forming with case in this condition.
I will be doing a light barrel break-in while fire-forming. Wondering if a mid-range load for the .257 Roberts could be used? Capacity of .25 Ack. Krag Improved only slightly more than the Roberts.

My Krag Ackley imp is full length, and capacity is more like the Roberts imp. I fireformed with a stiff standard Roberts load of H335 and 85 gr BT. My main load is a 115 Berger at 2850, and this is a moderate load.