4570 missfires

[0457john]

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?

[Super Sneaky Steve]

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.

[44 AMP]

Which is misfiring, the rifle, the revolver, or both?

[mehavey]

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?

[Gdawgs]

Did you use Large pistol primers instead of large rifle?

[James K]

It would help to know the type/brands of rifle and revolver.

Jim

[Mike Irwin]

Going to move this to the Handloading section.

[condor bravo]

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.

[T. O'Heir]

"...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.

[Magnum Wheel Man]

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...

[mehavey]

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

[Jeffm004]

FTF in one gun or both?

[rightside]

Where'd he go?

[snuffy]

Where'd he go?

The troll went back under da-bridge. Probably to find the answers to our ???¿¿¿

[Deja vu]

I use large Magnum Rifle primers (Winchester brand) in my BFR 45-70. They seem to work well.

[Gdawgs]

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

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.

[44 AMP]

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.

[condor bravo]

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.

[0457john]

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.

[Magnum Wheel Man]

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...

[condor bravo]

You still haven't said whether you were using pistol or rifle primers for the six rounds but using pistol primers is what you seem to indicate, so we're all assuming you did use pistol primers and that is where the problem lies. There is nothing to blame the Starline brass for; it was expecting large rifle primers.

[stubbicatt]

If you insist on using large pistol primers, if indeed that's what you are doing, you might consider seating the primer over a sheet of single ply TP. The primer pocket sized wad of TP will be punched out of the square of tissue, and seat firmly on the bottom of the primer pocket. Scott brand works good, and a roll will last the rest of your life in this application, heck probably "the other," intended, application as well. I'd reckon several hundred under primer wads in one square of TP. Its an under primer wad, and might give you just the little bit of "deck height" needed to make the pistol primers reliable.

Some guys do this when shooting black powder cartridges, and it works for them. Just be sure to clean the primer pockets when decapping, as nobody wants stained, burned, TP in their flash hole...

[mehavey]

Darn !

Here I've been using barenaked LP primers in my two 45-70 & 45-120 Sharps,
my 45-90 Rolling Block, my 45-70 `95Marlin, my 38-55 HighWall.... and all the
while not knowing it couldn't work in Starline brass !!!

[condor bravo]

Well, bottom line seems to be that pistol primers may work well for some guns but not for others. Good choice is probably to use what works well for you. If you are getting misfires with pistol primers, don't use them; easy enough to switch to the others. My .45-70 would probably work fine with pistol primers also.

[gyvel]

For those unaware, .45-70 revolvers were made for a number of years by the late master gunsmith/machinist Clarence M. Bates. If you run into one marked "CMB" you have a rare treasure. He also made one of a kind single shot rifles as well