Guys -- Sorry for being non-specific. I need a caplock patent breech (to avoid needing a drum) to build a slim Hawken-style rifle, in .40 caliber. I would be thrilled to find a 13/16ths patent breech for that style of rifle; could easily file away the "not-needed" metal. Where would I find one of those? I can't afford to have someone "custom build" one for me. Tks! -- paulallen, tucson az
When you embark on one off special projects that are far outside typical it becomes necessary to make parts.
So you have to plan to project for what is available rather than what you want as "ideal".
IIRC you are making kids rifles. In this case I would go with a breech I could obtain and then shorten or taper or swamp the barrel to reduce the weight.
You will have to re-think the project or have a breech made.
If you make the rifle too small the youngster will out grow it in nothing flat anyway.
To be honest most moderns want their MLs too light anyway.
The rifle I built for my 12 year old son was a 7/8 x45x 36" and I stocked it at 13". H e is a grown man serving with the Marines and even now only weighs 136-140 pounds. He was not a large 12 year old but could shoot the rifle well. I can still shoot it, its short but still useable.
It could have been lighter and shorter in the pull to be a perfect fit. But in a very short time it would have been pretty useless.
Dan