About 5 years ago I'd cast some 355gr Paul Jones elliptical bullets for some experiments.   Today I decided to try shooting them breach seated out of my 38-50 Remington Hepburn 1:12 twist silhouette rifle.  I've only ever shot black powder fixed loads out of the rifle previously.  I made a really crude plugged case breech seater with a fired case and a wooden dowel.  It shot surprisingly well.  6 of 8 shots in the 25 ring or cutting it, and two just outside in the 24 ring, with no wind flags out at all.   

I wasn't sure where to start with velocity so started pretty low.  It still needs more powder ( currently at about 18.6gr IMR-4227). I wonder if that heavy bullet might want a slightly slower powder.  Anyway I thought some might find it interesting.  The bullet is a little unusual as over 60% of the length is in the nose.   

Chris.

Hi Arnie,
It's 1.45" long.  It's some sort of custom Paul Jones bullet.  It looks like a mini groove elliptical bullet.  The driving bands are about 0.55" long and the nose is about 0.9"!!

The driving bands are tapered so whoever ordered it planned to breech seat it, or seat it super shallow in the case.

I'm going to try it again on Monday with black powder and smokeless.  This rifle was originally going to be used as a silhouette rifle but it hasn't shot as well with BP as my Shiloh 40-65's so far so I decided to try a few smokeless experiments with it.  I was really surprised at how easily it held the 25 ring.    

I also have a couple of new BACO 38 cal molds to play with.  Shorter bullets.  One is the JIM 376317E3 which is one I accidentally found.  The BACO web site doesn't sort it properly so it shows up at the end of the 40 cal bullets.  I'll bet they don't sell many because most 38 cal shooters would never see it.  It's a 1.31" long elliptical bullet.  I was looking for something similar to a Lyman 330gr Postell.  I have that Lyman mold but the vent lines are cut way too deep so it's a real pain to cast with.   

Chris.

Chris
Here are my two favorite loads for my 10 twist 38-50.
One on left is my 371359E at 1.42" long over 63 gr Swiss 1.5
and the one on right is my 371360E , 1.46" long over 68 gr of a very early dense Swiss 1.5.they clock 1370 and 1405fps respectively. BOth bullets weigh 355 gr in my 9+1 COWW/Lino alloy. 
The 371359E is length for Kurt Altenburg's 12 twist rifle.
Shoots well for hin. And both shoot well in my rifle.
As you can see, they are seated very shallow in the cases and
are mostly bore riding in the barrel when loaded--almost breech seated. 
I suggest you go to a 1.4 to 1.42"max bullet length for that 12 twist barrel
beltfed/arnie

I won't likely be getting any more molds specifically for this barrel.  I've sort of given up on it as a silhouette rifle anyway.  The chamber dimensions are so much tighter than my CH4D sizing die that making brass is a huge pain in the butt.  I'm just playing around with it to see what I can get out of it.  If this bullet shoots well breech seated to 300m then I can be happy with that.   

Chris.

That is basically what I do.  I have formed cases for a different 38-50 about 10 years ago.  No problems at all, but this rifle is a different beast.

This CPA's chamber is more than 0.005" smaller at the case web than any dies It have.  I have taken 1/4" off of a .303 British FL sizer and it's still not enough even if I drive them in without a shell holder.  The few cases I'm using now are still a little too tight after doing the above, and also removing a little bit of thickness at, and in front of, the web on my mini lathe.  Basically I'd need to get a custom sizer die made up.   

Not a huge deal.  I have a few cases to breech seat with and so far the rifle seems to shoot nicely that way.

Chris.