.32 M&H jamming issues

[backpacker336]

As the title says, I have a 32 M&H that keeps jamming after 3-4 shots. When I inspect the primers it looks like they are backing out slightly (3 sheets of paper thickness). I am shooting .32 S&W black powder rounds with cci small pistol 500 primers and a 45grain round ball.

Wondering if anyone else has ran into this problem and come up with a solution?

 

[lonapir12]

Primers backing out usually means 3 things:

1) excess headspace, you will need brass with a thicker rim

2) excess cylinder endshake, which causes excess headspace

3) too light of a charge, the recoil force should "re-seat" the case onto the primer

 

[backpacker336]

Cylinder is pretty solid and has no end shake.
Case is filled with good compression of bp (if i go anymore you cant open the gun to eject properly because the cases expand too much) I am going to try some full size S&W long with a proper bullet and see how it does. Right now I am using a S&W .32 with a round ball. Just waiting on a mold so I can make some soft bullets for it.
Would a different brand of primers make a difference? Right now I am using cci 500 sp primers.

 

[vagrantviking]

I would agree with the previous post.

My first thought was insufficient pressure. The same thing happens if you try to fire wax bullets with just the primers in an unmodified case. Your idea of experimenting with heavier charges and bullets should tell you.

Not sure exactly how the head space issue would be diagnosed beyond just taking a close look at the case fit. You might be able to get some sort of feeler gauge in between the recoil shield and the case through the loading gate.


Great little gun! I have a couple Merwin Hulberts in 44 but only one is barely in firing condition.

 

[backpacker336]

I tried a different load... .32 S&W long with a 84 grain wadcutter, having similar issue. I can fire 4 shots before it jams. The cartridge was loaded with black powder just above the bullet depth 3fg. Pretty sure the primer is flowing into the firing pin hole.

 

[vagrantviking]

I think you have the problem identified.
It should be giving the primers a pretty decent hit so you could try using a harder primer. Possibly even small rifle primers.

The best thing to do is bush the firing pin opening but that's not a trivial project for most of us. I have a couple guns that need it but am still working up the experience and nerve to start.