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Hi,

I've recently started shooting a 45-70 Trapdoor Springfield. It's shooting a duplicate of the correct 45-70-500 arsenal round, except I'm only loading it with 67 grains of ffg.

My problem is that it is shooting a lot higher than it should. With the sights set to the minimum elevation it is shooting about 24" high, when it should be about 12" high at 100.

I'm wondering if it's my technique that is pushing it high. Shooting from the bench, the muzzle rises a lot, so I'm thinking that as the bullet travels down the barrel, I'm imparting extra rise. That is, the muzzle is climbing before the bullet exits.

How do others go around controlling this (hold it tighter, perhaps)?

Any advice appreciated.

Have you read Spencer Wolf's take on the 45-70 in the Trapdoor?

Yes, I have. Only thing I've not done is drill the flash holes, but I'll do that for the next load.

Spence doesn't really cover firing practice, apart from the candle shoot.

Spence is pretty emphatic about what needs to be done to get the ammunition to perform as per the originals, my experience has shown his words to be correct in my case.

He does say also that the Trapdoor is a negative jump rifle that shoots higher with lighter bullets and loads.

As you are underloading along with presumable less compression you will not be getting the cartridges velocity which will contribute to it shooting high.

Ok, I'll try running with the drilled flash hole and 70 grain load. I'm using the Saeco 500 grain M1884 bullet, so this should duplicate Spences loading.

I figured out the problem. The barrel was knackered, lots of erosion at the throat, probably caused by poor maintenance. I picked up one with a pristine bore that shoots to the sights. 1320fps is service load speed, which does work well.

Load is per Spencer's instructions.

Now, I'm going to have to skip the barrel from my first one to the States for a reline. It should shoot better after that.