Saturday, April 11, 2009

Unexpected Project - BP .45-70 loads

I have 2 .45-70s but I don't shoot BP in them. I have the .45-75 1876 SRC for a BP cartridge rifle. I cast the Lyman 457122 and 457192 which I lube with SPG lube for that rifle. I am using GOEX 2F for this and my Brown Bess carbine. So, I had all the fixings for an "express" loading of the .45-70.

The other day while working at Nuckols, a local conservation officer came in and was talking about his father and an old trapdoor rifle he had that he wanted to shoot. Our gunsmith is the person who got the gun in shooting condition and he says it is safe to fire but the owner's son is convinced he'll "blow himself up" with the old gun. Ammo is needed...

I was standing there having a conversation with somebody else and the next thing I know a box of .45-70 ammo taken in during a trade is being handed to me. It is now my task to help them load some BP .45-70 loads.

It went all right. First, I removed the bullets from 20 of the loaded cartridges using my kinetic bullet puller. The bullets are set aside for later use. They were 300 gr. Sierra JHPs.

I dumped the powder (the previous loader had used both 2400 and IMR 3031) into a single container and dumped the powder on the lawn. Why? Because I'm pretty sure he used 2400 and 3031 but I don't know with absolute certainty that he used 2400 and 3031. I'm not taking any chances. The lawn is a safe place to spread the powder, the rain making certain it fertilizes as well!

We then ran the 20 cases into a Lyman "M" die (this one marked for the .45-60 did just fine with the longer .45-70 case). This allows the soft cast lead bullets to seat without deformation.

An adjustable volumetric measure was set to 70 gr. and a charge of 2F poured from my Bess horn directly into the measure. The charge was tapped and leveled and then poured into a case. The powder was settled/compacted by tapping the case with a plastic ball point pen. I don't have a drop tube yet (I thought I'd ordered one, wonder where it is?) but this works well. These are modern Remington cases and with a properly seated 405 gr. bullet they might hold closer to 65 gr. 2F by volume. The shorter 350 gr. bullet allows the use of 70 gr. (by volume) of powder.

My original intent was to use a grease cookie (although I was going to use SPG) but this was considered unnecessary (we'll see) so the Lyman 457192 was seated directly over the powder compressing the charge by about 1/8". One does NOT want any air space between a BP charge and the bullet. As my dies were set up, this crimped the cartridges just behind the front driving band of the bullet. In the .45-75 I would be certain to adjust the die to crimp over the top of the front driving band (as the bullet is designed for this) but since this was to be used in a single-shot, a trapdoor, I felt this would have minimal negative consequences. So, I left it as it was.

The end result is a cartridge which should move the bullet out at about 1300-1350 fps muzzle velocity. Usable for deer hunting and certainly for getting the feel of shooting a black powder cartridge arm. The only thing left for it is for the fellow to shoot his gun with his cartridges. I hope it does for him what it would do for me.

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