comments on my Navy Luger please

[sheepherder]

Originally Posted by DavidJayUden

Surely no one had some sort of sight or scope mounted there?
dju

Shell deflector???

[John Sabato]

Any sight assembly mounted on a breechblock wouldn't last very long. The G-sheer forces involved would snap the mount screws in short order.

What I am submit as my guess is that this modification is some armchair engineer/gunsmith's idea to bore gas relief holes in the event of a primer being pierced... the holes would vent gases flowing into the firing pin channel, instead of blowing the firing pin out the rear of the breechblock.

I don't see the holes as a major threat to structural integrity... but is certainly not as strong as Georg Luger designed it...

A real shame to do such a thing to a Navy Luger.

[Ron Wood]

That is a very odd modification and looks very much like the breechblock of a Borchardt! I also agree that it probably was an attempt to vent gas from a ruptured primer. I forget which country routinely bored a hole in the bottom of the Luger breechblock for that purpose.

[sheepherder]

Originally Posted by Ron Wood

That is a very odd modification and looks very much like the breechblock of a Borchardt! I also agree that it probably was an attempt to vent gas from a ruptured primer...

When you say 'vent gas', you're referring to the entire powder load blowing back through the primer???

How prevalent was this, that the [Luger] manufacturers actually modified the firing pin???

From your identification, this is an early Navy (most or all of it). Was this some kind of well-known 'stopgap' modification before the fluted firing pins came out???

[Ron Wood]

I don't think the entire powder load blows back with a pierced primer...but I don't know for sure. The grooved firing pin that was a production feature later than this gun was designed for just that purpose, to vent the gases. I am sure this was not a factory "stopgap" modification as I know of no other Luger, Navy or otherwise, with this modification.

[John Sabato]

Originally Posted by sheepherder

When you say 'vent gas', you're referring to the entire powder load blowing back through the primer???

Not the entire load... the cartridge could fire but leak gas out that tiny primer pierce. I have seen it happen in bolt action rifles that someone used reloads that were mistakenly loaded with pistol primers not intended for rifle pressures...

Certainly not a pleasant experience for those in close proximity, but if the rifle is properly designed for it Vented Bolt and receiver e.g., M1903A3 Springfield, it should not be that dangerous.

I have never seen it happen in a Luger...

Originally Posted by sheepherder

Was this some kind of well-known 'stopgap' modification before the fluted firing pins came out???

I guess Ron Wood is a much faster draw than I am... He finished his post before I hit the "save" button on mine

Obvioulsy not "well known"... just based on this discussion thread, but I do believe that the fluted firing pin modifications were the factory's response to reported primer failures... I doubt anyone could document the numbers of those failures at this late time. I also don't believe that the two holes on this example are original from the factory.

[John Sabato]

Originally Posted by Ron Wood

I forget which country routinely bored a hole in the bottom of the Luger breechblock for that purpose.

Wow... I bet if a primer let loose with the modification described by Ron above, that the gas rush would probably blow the magazine right out the grip!

[sheepherder]

Originally Posted by John Sabato

Wow... I bet if a primer let loose with the modification described by Ron above, that the gas rush would probably blow the magazine right out the grip!

I can recall pics of such a catastrophic blow-down, probably right here on this forum...Mag body still in place; bottom blown out and spring hanging down...

However, if the Borchardt had such a venting mod to the breechblock, why not the Luger??? Especially after going to the 9mm Parabellum from the 7.65 Parabellum (essentially a shortened 7.65 Borchardt)...

[aolis110]

The holes are drilled through to the breech block chamber. They do appear to be vents. They also appear to be factory, but I'm only a novice. If it is an after factory modification, any idea if it was done in the U.S. or Europe? I have included an image with my Mauser for comparison. I wish I had my good camera. Thank you, Bernie.

[rhuff]

Thank you for the additional photo of the breechblock. I have never seen this mod on a Luger before. There is sooooo much to learn concerning P-08s.

[LugerVern]

I thought vents holes at first too but the picture of the breachblock looks strange to me and the more I looked at it the more concern I had. It is most likely a trick of the camera but what is that groove near the top front nearest you?
interesting!

Vern

[DavidJayUden]

Considering that it is the first of its kind that we have seen, it will be pretty difficult to determine where or when it was done. However we seem to be well on the way to "why".
So if the holes end in the firing pin chamber, is the breach block weakened to the point that it should not be shot?
If it were mine, I'd be at the range right now. Just checking it after each shot or 2...
dju

[John Sabato]

Originally Posted by DavidJayUden

So if the holes end in the firing pin chamber, is the breach block weakened to the point that it should not be shot?

Originally Posted by John Sabato

I don't see the holes as a major threat to structural integrity... .

I don't think I have ever quoted myself before!