Hardest/most elaborate case conversion you did?

[challenger_i]

Making a rimmed version of the 6.5 TCU from 5.6x50R. 1st trick is finding the parent brass!
Anneal, FLS in a Hornady die (decapping/expanding stem removed), trim to 46mm, fire-form in a chamber insert made for 410 scatter gun (hey! I had a special chamber reamer made for this "non-standard caliber: may as well get some use out of it!), neck ream the case while seated in the sizing die (had my gun doctor make a reaming tool to fit the Hornady die: works like a champ!), Fire-form again. Load, go punch paper.
Is TRULY a labor of love, and I am pleased I have 200rnds completed, so as I NEVER have to do THAT, again!

[Good Cheer]

Recently found a long ago bunch of formed, annealed, turned .308's that I'd made out of .270 Winchester for precise necks.
Hardly a tough or elaborate conversion job but hey OK it was fun.

[Ben_51004]

Old thread, but good stuff here! I've done .40-65 from .45-70, that one's a no brainer. Slightly more challenging was .221 Fireball from .223 Rem. Pretty easy with C&H forming dies. Currently making .219 Zipper from 30-30 Win. Form #1, Form #2, file trim, FL size, expander die, final trim on Forrester trimmer, then neck turn. That's the most involved conversion I've done, but it's working.

[barryjyoung]

I convert 30-30, .219 Zipper, and a few other cases into two different .219 Donaldson Wasp cases. One of the chambers is longer than the other. This also requires reaming and turning the case neck after three dies to neck it down and push the shoulder back. I also make 6 Dasher from 6BR using a Whidden hydroforming (pain in the butt) die. I suppose I could just fireform, but at the price of components, that is no longer the simple fix it once was.

[15meter]

Stumbled across this old thread while looking for something else, figured I'd drag it back to the top of the pile to see if any body else has case conversion horror stories.

[lightman]

Probably making 357 Herrett cases from 30-30 cases. Not that hard but more than simply resizing and trimming.

[moosehunt]

.404 Jeffery cases from .300 RUM. The necks come out .010 to .015 short, but they work fine. Obviously .375 RUM would be a better starting point, but those are hard to come by.

[steveu]

280 Ross from 300WM without a set of 280 Ross dies.

[Randy Bohannon]

40-50 SBN (Sharps Bottleneck) found a set of RCBS Forming dies on EBay and bought a set of CH4D dies to use 45-70 brass. I’ve been advised that Winchester brass is the ticket for the 40-50 SBN reforming for the Shiloh rifles.
I bought 20 pieces of 40-50 SBN from a company called Ammunition Artifacts it’s Starline brass. Trim length is 1.775” so I bought a jewelers saw and use the RCBS forming die and a washer to trim near final length then final length on my Forster trimmer. This is a much overlooked cartridge, the smallish cartridge lends itself to smokeless powder quite nicely and the form die isn’t really needed as the CH4D dies will form the brass even without annealing but annealing is required for B/P.
I’m hoping Shiloh starts my rifle this year I ordered it 25 months ago. It will be the only Military Carbine chambered for the venerable 40-50 SBN that Shiloh has done.

[RJTyler]

1) 30-30 Winchester to 30 Remington

2) 300 Winchester Magnum to .410 shotshell

[15meter]

1) 30-30 Winchester to 30 Remington

2) 300 Winchester Magnum to .410 shotshell

Details on the 300 Win Mag to .410 shot shells would be cool

[RJTyler]

Allow me to preface this explanation by stating that my machining skills are very basic however I am blessed with a hobby size lathe which eases the conversion somewhat. I read about this conversion, perhaps here within Cast Boolits somewhere but when and where escapes me at this point. I had 17 300 Win Mag cases in my brass stash and no rifle to use them in so I thought I would see if I could figure out how to do it.

1) I measured the base of several fired .410 cases at about .480 from my chamber (Savage 24 22/410). I placed the 300 case into the 3 jaw chuck (base out, neck in) and clamped it with about an inch or so protruding. The case ran reasonably true when secured in this fashion. I then used a 1/8" parting tool to trim from the front of the belt to the rim down to around .480". Fast forward to the end of the conversion process, it turned out that .480 was still quite a bit too large to allow chambering and I ended up reducing the diameter to no more than .473 and if I ever do this process again, I will just use the depth of the extractor cut as the appropriate depth. I also then taper cut from the front of the reduced diameter, towards the mouth, because the next step in the process was going to be to reduce the rest of the case diameter down to around .473 or whatever would chamber.

2) I turned a "reducing die" out of a piece of 1 1/4" round stock about 1/2" thick. I drilled, inside turned, and then polished to an inside diameter of about .478". I was shooting for .475" but this is where it ended up. Turns out that it doesn't really matter that much as long as the end result is small enough to chamber properly.

3) I used a 20 ton hydraulic press to push the case from step 1) into the step 2) die until the rim touched the die. I eased the pressure and rotated the die/case 180 degrees every 1/2" or so to minimize the fact that it is impossible with this crude setup to push the case perfectly straight into the die. I tapped the case out of the die using a small hammer and brass rod. The cases popped out with ease. Lucas Red n Tacky was the case lube because it was handy.

4) The resulting sized cases were mildly distorted and thus would not chamber so I went searching for a way to true them up. This evolved into running the cases full length into a 35 Whelen sizing die (depriming stem was removed) using my RCBS press. Multiple short strokes and liberal application of case lube were necessary. The resulting case will then chamber properly in the .410 chamber. While I was at the 35 Whelen die I decided to open the necks up to .358 prior to fire forming.

5) I annealed the neck and shoulder of the case hoping that it would help avoid splitting during the fire forming process. I still ended up with a couple of cases with splits. Fire forming consisted of 7 grains of Red Dot (Lyman Ideal Handbook No. 39, page 130.) covered by a tamped newspaper wad, rice filled to the neck, and then another wad of newspaper. This load seems to form the cases reasonably well. I trimmed the split cases back to remove the splits and they are perfectly usable cases, just a bit shorter.

6) The full length cases should easily accommodate 3/4 oz of shot. I decided to try the Lyman suggested load of 7 grains of Red Dot with a hand punched .375 x .135 card wad over the powder, sufficient tamped newspaper to fill space, 1/2 oz of #8 shot, and a thin card overshot wad sealed with hot melt glue. At 20 yards (full choke) nothing small would escape the pattern. At 25 yards a small critter may find a thin spot.

I will run these over the Chrony when I get a chance, but they feel mild compared to a factory loaded 2 1/2" cartridges.

If I ever run across some unusable magnum brass I may try this again. The resulting cases are serviceable and actually fit the chamber very well. It was a good learning experience. Fussing around with the reloading components will no doubt continue the learning experience.

Best,

Ross

[K43]

219 DW long from 30-30 has been easy using a Redding forming die set, RCBS trim die, and Redding die set.
Making 7.62x25 and 7.63/30 Mauser from 223 however, was a pain. Too many steps to get slightly undersized cases that look like guppies after firing. Too me, it wasn't worth the time and effort.

[midnight]

I’d have to say the 219 Don Wasp also. I have three, a Remington rolling block, a large Greener Martini, and a T/C Encore. They all require different neck diameters and case lengths in addition to the usual case forming and fireforming. I make them from 30-30s so at least cases are common & they used to be cheap. Not so anymore.

Bob

PS: I started wildcatting easy with the simple 30-338. It kind of grew from there. Funny how that stuff works.