Mako,

I do work on, collect and restore Antique Snowmobiles, 1968 and older.
It's been my obstion ever since they were new.
My son & I actually take them on trail rides and race with them,
along with our many friend in the Antique Snowmobile Club of America.

And yes, that was the Cylinder Press which I had built during after hours at work.
Almost all of the material came from the scrap barrel at work,
I think the ram was the only purchased part, a 1/2" ground rod.

The problem I see with modifying an allready built collet is holding it while machining,
they want to spread on you because of the slits but this can be overcome.
The issue of building a new one like I did, they need to be heat treated so they spring back after crimping.
I used a piece of 17mm O2 Drill Rod for the collet. I did all the machining before cutting the slits.
Then before heat treating it, I put it on a mandrel and wrapped it with mechanics wire tied to hold it against the mandrel.
It was a real pain, but I didn't want it to warp. I tried one without heat treating and after a few rounds it didn't spring back.

Looking at the 3 cartridges in the picture, one can see the ".44 Colt & Remington" was crimped in a collet.
Maybe the rest of the cartridges were actually rolled to creat the rolled crimp.
It would be possible to do so with a tubing cutter, but I think this would get old very quickly.

As far as re-using stuff already made for something else, it just seamed the way to go.
Why go through the troubles of building the same piece for a different project when it's right there?
I also used the cylinder press as an extraction tool for a little swaging die I built.
Somebody had posted a picture of the Taurus Hollow Base (unavailable now), so I attempted to copy them.
I made a swaging die to swage a .375 round ball into the 36 caliber hollow based conical.
I needed a way to get the final product out of the die, as I didn't like pounding on it with a hammer.
In the picture below the Taurus Hollow Base on the left, with my copy on the right.
I will say the one downside of retirement is the loss of the equipment we were allowed to use.

AntiqueSledMan.

Howdy Deacon,

Not sure it this helps, but my experience with .38S&W is for an 1851 conversion with the original dimensioned .385 bore. That is a substantially larger than your bore. I have had some success with soft hollow base wad cutters, even with light charges of Amer. Select powder. I suspect that might get you started while you research your mold selection.

For what it's worth,

Rev. Chase

Morning y'all.
Coffee and tea are hot.

Learned good info. Took the Stop The Bleed class. Stopthebleed.org. There is a free on-line course.

I took the online course as part of my CCW course. Bought and carried quick-clot in addition to a trauma kit.
Good stuff when used properly.

Hit 72 and sunny here today, started out with drizzle, then by mid-morning turned real pretty. Worked today and then Sheepdog duty at the Spanish Ministry at Church. Y'all have a good one.

Rather than the typical 200 grain flat point CAS .44 Russian loads, I used Bear Creek's 246 grain, conical round nose .44 Russian/Special bullet over 5.3 grains of Unique.  That is listed in Lymann as a factory duplication load.  That should smack the plates with authority.