Although many love the voluminous cases from the black powder era, recent propellants don't require all that volume. Some propellants are position-sensitive, or need close attention to % of case fill, or need a certain bullet weight (light / heavy)....

So as I pondered light charges in a .38-55, that cavernous hull mocked me... A sub-cal adapter is right out. What existing round could be used? Not a lot of commonly available (read: frugal) pistol cartridges with bullet diameters in the .375 - .380 range.

How about seating a bullet deeper into a straight-wall case, so as to gain the equivalent of a 1.290 case? Got to leave the full length of the case (@ 2.120 or so) because of the chamber, but it solves the problems caused by a (quite) short round in a long chamber (Like a .45 Colt / .410 combo...). On the safety side, such loads are quite distinct, and it would seem that stuffing them into any sort of action would not result in excess pressure (assuming reloading practices are correct).

Downsides... The case thickness is tapered, so I dunno how far a lead bullet can be seated. 

This sure would take screwing the seating stem down quite a bit.

One additional problem with seating the bullet so deep is that the bullet would have a long run up to the rifling and would have accelerated to a much higher speed relative to a bullet seated near the rifling. With lead bullets, this would lead to considerable stripping of lead in the rifling, and I would suspect more gas cutting.

jy3855 wrote on Sep 12^th, 2018 at 9:54am:


A point to ponder. Which is worse, long (inch or so) run with no rifling, but close to bore diameter, followed by a quick snap when it hits the rifling, or a short case, where the bullet is about .0009 per side too narrow?

Hmm, my first thought is something with a wide base band. The oldtimers fought stripping with such. Not sure if a gas check would manage to give enough grip. Looks like a hard alloy, at least water quenched, would be a reasonable contender...

But... how many bullet moulds like this exist...

I feel the same way as Joe. No need to reinvent the wheel when there are plenty of very successful loads that have proven to be very accurate in the .38-55 for decades.
I'd be concerned with bullet jump into the rifling as jy3855 mentioned. But also exposure of the base bands to the burning powder during firing. Wonder what would happen to the base band seated that deep during initial ignition of the charge?
It's much easier, and cheaper, if you're frugal to use existing successful load data, than to start down a path unknown.

marlinguy wrote on Sep 12^th, 2018 at 11:19am:


The bullet is in full contact with the case walls. It is NOT like deep seating in a bottleneck case. If the bullet is of the correct diameter, how are the base bands exposed any more than a bullet seated to a normal depth?

Kurt_701 wrote on Sep 12^th, 2018 at 12:56pm:


For any conical, I would expect no issues with normal seating. This is for a single shot, not a magazine where bullets might be telescoped back into the case.

I have seen period adds for indentors.

PS. thanks for fixing the image size...

calledflyer wrote on Sep 12^th, 2018 at 11:48am:


So what of the 32 (?) wadcutter rounds where the entire length of the wadcutter is inside the case?

ohland wrote on Sep 12^th, 2018 at 12:41pm:


Measure the outside of a .38-55 case, and you'll see it's not truly a straight walled case, but a straight taper case. So the deeper you seat the bullet, the more gap there is between the bands and the case inside walls.