PDA

View Full Version : Springfield Trapdoor 50-70



Jethro
09-12-2010, 06:55 PM
I have an Old 1868 Trapdoor that I have sucessfully shot Buffalo Arms Co., 50-70 Sharps Ammo in 425 gr. .0512 dia. through.

The cost of the ammo is enough to make me shoot it only on the 4th of July so I bought an RCBS 50-70 set with decapping and sizing die and a bullet seating die. Also have a Lee bullet mold in 450 gr. 0.515 dia. I would like to duplicate the load from the Buffalo Arms Co. Except use Jim Shockey's Gold which can be substituted grain for grain with black powder. Does anyone know the powder load that Buffalo Arms uses?? I assume it would be a little different with a heavier bullet.

Thanks.

Ole
09-12-2010, 07:28 PM
I can't help with your question, but welcome to the site. :drinks:

mpmarty
09-12-2010, 08:41 PM
If the powder can be substituted on a grain for grain basis I'd try to work up to the original 70 grains starting at around sixty grains and going up a grain at a time.

dale2242
09-13-2010, 08:40 AM
Jethro, Pull a bullet from a Buffalo Arms round and weight the powder charge....dale

Moonie
09-13-2010, 10:59 AM
The only help I can provide is to mention that the new (current) Handloader magazine has an article on the 50-70.

GabbyM
09-13-2010, 12:18 PM
Lymans old third edition handbook has 50-70 loads which include BP, Pyrodex and duplex loads.

the BP load for a Lyman 512138 at 440 gr wt is 48 to 60 grains of FFg. 48 grains shows 987 fps. I'd use a wad over that if there is air space under the bullet. Although the book shows no filler with 48 gr of FFg your bullet may differ in seat depth. Don't know what Shockleys requires in the way of powder compression.

They used a Sharps rifle so that max load of 60 gr FFg may be a tad much for a trap door. Especially with replacement powders that usually runs higher velocity.

If it were me I'd shoot a duplex load of holy black..

Jethro
09-13-2010, 09:08 PM
Thanks Everyone.

I get a good compressed powder with 70 gr. of the Shockey's but I will try 60 with a wad and increase a grain at a time as suggested.