Thread: High Pressure or weak firing pin spring

Hello Guys

I'm getting some primer extrusion back into the firing pin hole. The loads I've experienced this with are 41.0gns Re-17 behind 120 Amax's and 41.0 gns AR2209 behind 125 Noslers. According to Quickload pressures for both should be moderate (around 55,000 psi) and the velocities I'm getting correspond with what QL predicts. If I back off it reduces but there is still not what I'd think is a full indentation. I did change out the main spring with another I had but I don't have any"new" ones to try.

I'd photograph them but I'm a hopeless photographer.

Does anyone have photos of what they consider to be primer extrusion from a weak firing pin- I can't find much of any use on the 'net.

Thanks

what calibre and have you taken seating depth into account?

Which rifle/action are you using ?

I'm guessing 6.5x47L and a Rem action?

If yes, get your firing pin hole bushed.

Edit - I'm running purely from memory in relation to the loads so I'm probably WAY off

Oops - lost the post half way through typing it and didn't recheck it so sorry for only half the info . . .

Mauser 98 action, 6.5x47L, and Quickload has been calibrated with fired case water capacity and seating depth. As its a Mauser I'm being careful not to "hotrod" it, I think a max pressure of 55,000 to 58,000 psi is reasonable though. Its a new build with careful headspacing and is showing excellent accuracy. The 'Smith wasn't asked to bush the firing pin but I probably should have as I know 6.5x47L is known for this, although I wouldn't have though it would manifest itself at modest pressures/velocities (velocities are in the 2750 fps range)

Get it bushed and problem will (probably) go away.

Using a Mauser 98 for a high pressure cartridge???? And a short one as well that probably would have feeding problems?

"Bush the firing pin" - on a m98 ??? - let us know how that works out for you.

It's 2014, move with the times. There are numerous cheap commercial factory actions that would have been better choices than an M98 to start with. Mauser actions should ideally not be used with cartridges over 45k to 50k PSI max. (Generally speaking, as the quality of heat treat varies so much from various makers and vintages.)

Feeds like a dream as it was designed for short cartridges, its a Oberndorf Model B Kurz if you know what one of those is ? My rifle is built on a commercial action from 1929, so the heat treatment is probably not what you'd expect from a post war action, hence my comment about keeping pressures moderate.

What I asked for is a photograph that might enable me to identify if I have a weak main spring, or educated opinions as to whether or not the loads I was using might be producing pressures beyond what the data I have available to me suggests.

So generally speaking I don't feel out of step with the times at all but thanks anyway.

Tentman, what are the chances of getting hold of a couple of factory rounds to see if you get any cratering with those ?

federal primers? they are fairly soft, could be another cause. how bad is the extrusion?
greg

The CCI 450 is -the- known primer for this cartridge.
Gives excellent ignition and is pretty robust too

Originally Posted by 6x47

The CCI 450 is -the- known primer for this cartridge.
Gives excellent ignition and is pretty robust too

+1 also BR4 work well, my load is 41gn Re17 with 123amaxs.

Originally Posted by dfmaisey

"Bush the firing pin" - on a m98 ??? - let us know how that works out for you.

Is there any reason why a Mauser 98 bolt CANNOT be bushed? (to eliminate a badly oversize firing pin hole)

Just interested, because I have one (well, actually a Parker Hale 1200) that falls into this category.