45-70 Trapdoor Loading

[NRAhighpowershooter]

I have a 29.5" barrel 1883 Trapdoor and have been loading 405gr lead in it with 34.5gr IMR 3031 for a while and accepting so-so accuracy. I then tried 500gr lead with 35gr IMR 3031 and the riffle loved it! My question is this.. is the 35.0gr of IMR3031 ok or? I crono'd the load and averaged 1255fps I can't find any load data using 3031 with the 500gr bullet. I'm using the 3031 because it's a bulky powder and at 34-35 gr there is no need for filler like the other powders and I don't want to shoot blackpowder through it. Plus I have a lot of 3031 on my powder shelf...

[Sandspider500]

I checked Lyman 4 cast handbook and your load is in the range for 1873 trapdoor.


Lyman 457125 500gr 2.835 OAL
Lyman 457132 535gr 2.930 OAL
Lyman 457658 480gr 2.990 OAL
Saeco 745 525gr 2.885 OAL
Saeco 020 540gr 2.800 OAL

You are below most of the starting loads with 3031, so pressure wise it looks fine. If it's accurate and works for yah you're good to go.

[IrishJoe3]

Do you mind sharing what bullet you're using? What kind of grouping are you getting?

[NRAhighpowershooter]

I'm using the 500gr Lee mold 459-500-3R and I'm using Lee bullet lube
as for groups.. 12" at 200yds...
It good enough for me to have fun with it.

[Steve45-70]

I'm using the 500gr Lee mold 459-500-3R and I'm using Lee bullet lube
as for groups.. 12" at 200yds...
It good enough for me to have fun with it.

I shoot the same bullet. I want to buy a Lyman 530 AJ3 mold but the Lee is fine for plinking. I use black powder out of my Italian 1873. I use a beeswax, Crisco, lanolin and canola oil bullet lube.

lee bullet 500.jpg

[IrishJoe3]

I'm using the 500gr Lee mold 459-500-3R and I'm using Lee bullet lube
as for groups.. 12" at 200yds...
It good enough for me to have fun with it.

Huh ok. Using the bullet as cast or do you size them?

[kcstott]

quick load shows with a 2.550 COAL 23KPSI chamber pressure with 35g of IMR 3031. 28KPSI being max

[Sandspider500]

I don't think this bullet is designed to run in your 1895, 2.55 would be very short.

[Sandspider500]

Should be around 2.78 OAL