New 1858 NMA Project

[Michael Tinker Pearce]

Here's the various bits-

 

[gasmandave]

Linda's favorite suggestion was 'The Dandy,' so there you go. Spent basically the whole weekend working on this gun. Made a base-plate with a rebounding firing pin and a cartridge pass-through and tested the gun with primed brass. Then I made a swaging block and a few other tools and laboriously reloaded 24 rounds by hand. The load is super-light for testing, but if it works out I'll creep up the power. I loaded a 200gr Heel-base LRNFP over 3.0gr. of Trail Boss. Out of my gun this ought to get about 550fps. and about 134ft/lb of energy. I hope in the end to get 750fps and 200+ ft/lb from this. Not a powerhouse, but then neither was the original. The Army load was a 225gr. conical bullet over 15gr. of FFFg black powder which was good for 650fps and 207ft/lb of energy.

I was left unsupervised late last night with the printer...
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Here's the completed gun- it testing goes well I'll detail-strip and refinish the gun-
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Mike, you're Killin me here! I truly think that's a work of art. Now I've got get 2 more 58 Remington NMAs to trade.

 

[Michael Tinker Pearce]

Mike, you're Killin me here! I truly think that's a work of art. Now I've got get 2 more 58 Remington NMAs to trade.

Make mine a Pietta Colt .44 next time, lol.

 

[Michael Tinker Pearce]

The 200gr. Bullet with 3.0gr of Trail Boss? Hilariously underpowered- the first four bullets barely made it out of the barrel, and the fifth didn't. I'm going to go with Trail Boss's recommendation for developing a load. Fill the case to just under where the bottom of the bullet will be when seated, weigh that and start with 70% of that weight.

 

[drobs]

What did you use for a rebounding firing pin on your base plate?

 

[Mn Fats]

I found that I liked the look of the squared-off loading lever, and I carried that further making a sight-rib.

The squared off lever was the first thing my eyes were drawn to. Really a unique look. I like it.

 

[Michael Tinker Pearce]

What did you use for a rebounding firing pin on your base plate?

I turned a firing-pin from a small punch and used a section of spring from a broken mechanical pencil. I simply staked the edges of the hole to retain it. Simple but it works.

 

[Michael Tinker Pearce]

The 3.0gr. loads were ludicrously underpowered, and in fact the fifth shot never even cleared the barrel! Trail Boss recommends loading the case to just under the seating depth of the base of the bullet then starting with 70% of that load. This method yielded a maximum load of 7.2gr. and a minimum of 5.0gr. After some experimentation I arrived at a load of 6.5gr. behind a 200gr bullet. I can't hazard a guess as to the velocity but it was sufficient to penetrate 1" into a kiln-dried Douglas Fir 2x6- much harder that the 1" pine board that was once standard for such tests. The board was free-standing and if it had been braced as is usual for such tests I am pretty sure it would have shot through the board. This round was never particularly powerful, and this will certainly be sufficient for target shooting and perhaps small game.