Oversize Firing Pin Damage
 

Most of you will know this, but a reminder wake up.
Shooter Lugers. Too long a firing pin will piece the primer and if it doesn't have post 1933 gas by pass cuts, on firing the high pressure blows the firing back as it has a seal. This compresses the firing spring, blows the firing pin retainer out the back of the breach block. Very Sad.
A friend did this and when mine wouldn't fire after the 2nd shot, I picked up the brass and knew what the problem was.
OK, remove blue, a spot of weld, then dress it up with the Dremel,
All my shooter have these 3 gas by passes cuts in them. Not hard to do.
Prior to this happen, I expected that there would be so much pressure, it would blow the sear bar out and do some really bad damage.

I don't know much about firing pins - which kind are too long ?
(I don't shoot a lot, but the few times I had pierced primers was more about the reloads than the gun....curious)

Even with factory ammo, if the firing pin sticks too far out from the breach block face it can piece the primer, that goes with any firearm. Lucky for me it was a 9mm and didn't cause too much damage, but a 308W may have been a different story.

I've never heard of a firing pin tip that grew like Pinocchio's nose before. If it sticks out too far, something is significantly worn, either the inside of the breech block where the striker bottoms out, or the striker itself. I remember seeing a post about a piece of factory gauging that measured F.P. stick-out. It was basically a precisely cut notch on the end of the tool, and a piece of a credit card filed out just as precisely was deemed an adequate substitute. Somewhere here at Luger U., there is a spec for this notch, i.e. the precise distance the tip of the F.P. was designed to protrude. If it's excessive, you'll dress the tip to gain the correct dimension?

Luger firing pins don't tend to be too long. It can happen of course but it's not common. The pierced primers, in a Luger, generally occur from excessive headspace.

Either from out of specs ammo, more common on the .30 Luger even with factory loads, or from a mismatched breech block that wasn't properly fitted to the gun.

Perhaps I have misread Kiwi Mark's post, but I interpreted it that he found that he had too short of a firing pin in his shooter Luger(misfire X2), so he built up the tip of his firing pin with weld and then dressed it down with a Dremel tool......obviously leaving it too long, producing pierced primers when fired. :confused:

Sorry, I'll explain. It's a 9mm, a very tired old lady, 1917 DWM and dressed up with some good looking grips. So off for a shoot, nothing done to the firing pin. Aftermarket mag. After 2 shots, it failed to fire the 3th. Picked up the fired brass, and I could see the pieced primers and could suck air through the case. As well as protuding too much, the diameter of the tip of the firing pin is 1.3mm. The spot of weld was added to the rear of the breach block where the firing pin retainer clicks back in it's final position as it had blow the very thin bit of metal out.
Luger manufactures started to do the gas blow back mod on the front face of the firing pin from 1933, 3 slots. Was it for this reason??

Most probably. I only use Mausers as shooters.

Here is what the gage looks like.
An original Kreighoff accepted gage, and one of my home made ones.

The min and max are in mm.

Thus the end of the striker(firing pin) should extend at least 1.1mm past the breech block face, and no more than 1.35mm.

Actually the fluting started earlier, about 1930.
Its stated purpose was to improve striker performance in case of buildup of dirt/oil/powder residue; no mention of gas bypass.

Many think gas by pass is the "reason" for the flutes, see the recent discussion here:
http://luger.gunboards.com/showthrea...ighlight=flute

The surest way to improve gas bypass is to drill a hole in the bottom of the breech block, just aft of the spot where the striker stops against the inside of the breech- this is what the Norwegians and others did fora gas bypass.

Better yet is PM, inspection and correction of a sharp or too long striker nose(firing pin).:evilgrin:

Can you please add / post a pic of this drilled hole?
Thank you!

I thought it was the Finns who used to drill the holes. But, I've been wrong before.

Finns, Norwegians, Swedes- aren't they all the same? Northmen?;)
(My apologies to and of those folks who are members.):cheers:

chr,

There have been several pictures posted on various threads,
When I get a chance, I'll pull my Norwegian and see if it has the hole.:D
Maybe someone else has a picture handy or remembers where it is.

Maybe a search for "gas escape hole" would find it.:)

Would be great. Thank you.

Goggle shows no picture.

Well, they were all Swedes once. ;)

Why would you expect google to have a picture?
Everything is NOT on the web!

Best I can do right now is describe it, it is an approx 1/8" hole, in the bottom of the bolt, on the centerline, just about at the edge of the "cone" on the inside that fits the front of the striker.

Did you try a forum search?:cheers:

Probably not or you would have found this one:
http://forum.lugerforum.com/showthre...as+escape+hole

And another one, too bad the link is dead, but a good example of a Finn luger with hole!
http://forum.lugerforum.com/showthre...=bolt+gas+hole

Great example of why pictures should be hosted on the forum server too.

I believe this is the pic you guys are thinking of. From my understanding the hole is present on all Finnish Lugers just in case of a pierced primer.

Yes,
that is it. Thanks for posting the picture!:)

Thanks to all.
I am thinking now to update my shooting Luger with this hole.

Gold idea or not, what would you say?

Can't do any harm, as long as it is a "shooter".