What Happens If You Accidentely Switch Ammo?
 

I was researching my 1902 fat Barrel and its written that the original mag was marked 9mm/cal to remind the owner that it took the larger 9mm. What would happen if a commercial 7.65mm round is loaded instead? Would it load or even shoot. I have a 1906 French contract which has an unmarked mag that would fit both calibre~ but has a 7.65mm barrel! Basically are they interchangable depending on the gun? Eric

The only difference between a 9mm gun and a 7,65x21 is the barrel and recoil spring.

Since the Parabellum does not have controlled feed (as the 98K Mauser) where the round pass up under the extractor at loading, the 7,65 would plunk to deep into a 9mm chamber. Even if it was held in place by the extractor it would fire with a plop and straighten the case, nothing more.

9mm COL is 1.169"
7.65 COL is 1.175"
So the magazines would'nt know the difference either.

In the Parabellum the round does, indeed, rise up under the extractor when stripping from the magazine.

--Dwight

The 9mm Parabellum round headspaces on the mouth of the straight walled cartridge.

The 7.65mm Luger round is a bottle neck cartridge that headspaces on the shoulder of the cartridge.

I don't recommend testing this, but would there be enough chamber support to ensure that the extractor would engage the cartridge rim, and enough support for the firing pin to actually strike into the primer?

Either it will go bang if it gets held by the extractor. And it wiil be poultry snatcher's scenario. Or, it will go all the way in untill the bottleneck shoulder hits the end of the chamber and nothing will happen cause the striker won't reach the primer.

The 9mm marking on the magazine bottom serves another purpose. It will avoid to inadvertly put a 9 mm loaded magazine in a .30 Luger chambered pistol. Those rounds will not chamber, and you will be either embaressed or defensless depending on the situation.

We used both as service pistols. First in different branches (Army and Navy), and after 1942 in all services except the Air Force.

I refound a 9mm/Cal injured old mag I bought years ago for $20 long before I bought my 1902 Fat Barrel. It appears legit~Looks like it got run over!!!! Eric

Eric,

I think G.T. might be able to improve/re-do the repair. Otherwise, we remember his exact copies of the walnut 9mm marked mag bottoms!

Tks I'll give him a shout!