what is the melting point of tin?  how hot does your powder burn? Just speculating, but I suspect that the "jet" of burning pressurized of powder gasses would do a lot of tin erosion down into the primer flash channel and cause blockage and weird stuff in short order.

Just have RMC make a few out of brass,  I have a bunch of 220 Swifts kind of made that way. solid brass with a .22? hole from case mouth to small rifle primer pocket flash hole.
If I was to do a larger bore cartridge I'd design a seating depth shoulder. Thinking seriously about trying some 45-70's that way as an experiment.  Kind of like an internal stop ring for straight or tapered bullets.  start with it shallow and mill it deeper if needed.
My only mental reservation is how well the thick/thin wall transitions and the brass RMC uses would work in the long run

me too,   I wonder how long a "flash tube" you can have and have it function reliably.

Re: pressure of short wide powder charge vrs tall narrow ones.    seems like that is the basis for a lot of the "short magnums" that are/were the rage.  I think that part of the theory is that you get a wider ignition/flame base that burns the length of the charge more quickly rather than a taller narrower longer burn. 
Yet, I have flintlocks that have patent breeches that have a significantly less-than-bore sized powder or at least ignition chambers, then there are the Notorious Coehorn mortars and similar mortar designs---but then BP ignites burns a lt diff. from smokeless.  Maybe doing too much apple to oranges thinking here.
  I wonder about the diff in bore size bullet base areas and how that factors.   For example take a .308 round with a 180 gr bullet and a .260 rem target round also w a 180 gr bullet and test them with the same powder charge.  I'd think the longer narrower bullet, if nothing else would have more surface-drag/friction in the bore--slowing the bullet down and boosting in-barrel pressure.
I'm thinking something like a .42 or .40 dia powder chamber dia under a 45 cal bullet,  maybe .36/.38 under a 40 etc.

hopefully someone who understands this stuff a lot better than me will chime in

MI-shooter wrote on Jan 1^st, 2014 at 2:11pm:


YES, I'm sure of the NUMBERS.  It SHOULD have been R42-43 on the B scale.  My bad; thanks!

Thanks, but this is an effort to reduce the volume to a reasonable PB cast bullet amount of powder in a HUGE case.  38-55 type of volume compared to 375 H&H volume - perhaps half.  The advantages include - one, the chances of double charging are greatly reduced; two - the ignition is better (less hang fires); three - the consistency of burn due to a closer to say 80% fill from 20% fill; and four the inner-shelf providing a controlled position of the bullet.

If you want to shoot a great big case with a little powder, put in the powder and then a filler, like COW. Nobody thinks COW etc causes rings, and accuracy with COW etc seems fine. Seems simple to me.

i was thinking a disc of nitrated paper or Zig-Zag to cover the 'flash tube" before adding the powder.  I think that is/was done in BP when they put a dab of 4F or even finer Null-B as an igniter in a duplex load

QuestionableMaynard8130 wrote on Jan 1^st, 2014 at 5:02pm:


I would love to read someone else's research on having done something similar.   

Everlasting cases are ok, but expensive.  I'm looking for a low-tech low-cost alternative.

Annealing the cases would be out of the question, but might not need to do so.