4570 missfires

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0457john

Inactive
I recently purchased a rifle and revolver in 4570 caliber. With the cost of loaded rounds so high I purchased 250 rounds of brass and some dies. I've only shot around 100 . When at the range last I had 6 misfires. The cause was the primers were set too deep. I looked at the other loaded cartridges and see I am going to have the problem with other cartridges. What would be my best solution?
 
How are you seating your primers?

If you're using your press, you can adjust it, but it has so much power you lose some feel.

I like to do it with a simple hand tool.

I use a Hornady tool.

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It's hard to set primers too deep in normal brass unless you are really crushing them.

- What weapons/models/manufacture are these 45-70s ? **
- What are your load combinations (bullet/weight, powder/weight, and primer type)?


** You really have a 45-70 revolver?
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As Gdawgs says, you are probably using pistol rather than rifle primers. What handgun is chambered for the .45-70? That would be quite a wallup with factory rounds. Definitely time to be doing some downloading.
 
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"...What handgun is chambered for the .45-70?..." A Magnum Research BFR(they claim it means Big Frame Revolver. snicker.) 10 or 7.5 inch barrel SA. Still uses LR primers with lever action rifle loads.
 
the fliers I saw for the BFR always said "biggest, finest, revolver"

could be a Contender as well, or one of those big Buffalo Arms ( if that's not correct, I forget the exact name ) 45-70 revolvers...

the guys that suggested the pistol primer issue are one of the most likely issues... even if you are loading for a 45-70 handgun, you still need to use rifle primers, as that is what the brass is formed for, & large rifle primers are the same diameter, as large pistol, but a little taller...
 
Large pistol primers are used all the time by BP shooters in everything from 38-55 to 45-70/90/110/120.
(I know I use them for everything in these cartridge family.)

In normal firearms this is not a problem at all, especially as the LP cup thickness is only 75% that of LR
 
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Large pistol primers are used all the time by BP shooters in everything from 38-55 to 45-70/90/110/120.
(I know I use them for everything in these cartridge family.)

In normal firearms this is not a problem at all, especially as the LP cup thickness is only 75% that of LR
Click to expand...

This can cause a problem in some firearms since large pistol primers are roughly .007" - .010" shorter than large rifle primers(depending on brands). So LP primers will seat into the pocket deeper than LR primers. So it may not cause an issue in some firearms, but could be problematic in others.

Small pistol and small rifle primers are dimensionally the same.
 
I only load .45-70 with large rifle primers, normally CCI. Never had any issues from 3 rifles or my Contender.

I don't run black powder.
 
Well perhaps we haven't addressed the actual question "what would be the best solution"? For the loaded rounds, continue to shoot them and try a second or third strike for any that do not fire. Or try cross firing the rounds in the other gun. Then hopefully you have an inertia bullet puller to disassemble the failed rounds. For upcoming rounds make sure you are using large rifle primers. We would still like to know if the misfires were with the revolver or rifle, or both.
 
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It's a magnum research with a 10inch barrel. I ordered 250 rounds of brass from starline. I've never had a problem with their brass before. I'm pushing 405 gr. fp with 42 gr of imr 4198. I reloaded those six trying not to seat the primers so deep hoping when fireing them the pocket will push out so that the primer will seat better on the next load.
 
case head will not move with "normal pressures" & you're just as likely to have misfires, when the energy from the hammer is used to push the primer to the bottom of the cup... you'd be much better off using rifle primers... that revolver should be easily able to handle those...

actually I'm not sure if it got mentioned, but if you were using pistol primers, & they weren't seated fully to the bottom of the primer pocket ( if they looked low, & you tried to seat them in the middle somewhere ) there is a good chance that caused the missfires... as the other guys that are using pistol primers stated, most guns have enough firing pin to reliably ignite the shorter primers, but they must be seated fully to the bottom of the pocket, or they suck up most of the hammer inertia finishing seating them...
 
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