What's the cause?
 

My Interarms swiss style has a peculiar tendency which I don't understand. Maybe you guys can enlighten me on the mechanics of the problem. With one of the magazines which came with the gun, about 50% of the time the last two rounds in the mag fire full auto. It is my understanding that the ejector somehow acts as an interrupt mechanism which prevents the gun from firing full auto. Not really important to me to get this resolved, but I would like understand the mechanics. It's really cool when it does fire this way, as it is so shoots the two rounds so fast as to be almost indistinguishable from a single shot. Also, the hold back fails to function periodically................Ideas???? G

Hi,

Do you use the magazines that came with the gun? (plastic bottom with either Mauser/Interarms and-or 'made in holland' on the spine).

My Mauser Parabellum really doesn't function with the magazines that came with the gun. I use Mec-Gars instead, they work perfectly, apart from the hold-open most of the time, as you mentioned as well.

G, The disconnecting mechanism of a luger is the plunger under spring pressure in the front of the trigger bar (sear). Perhaps your spring is weak or the plunger is sticking. I do have these new Mauser made Parabellum parts in stock, if needed. TH

I have had this full auto experience once, before I gave the gun a complete clean. I had only loaded 2 rounds in the mag, pulled the trigger once, it fired once and the toggle locked back. I was expecting a jam since I had had a string of them during that shooting session, but found the gun and mag empty. Impressively fast, I only heard one shot!!!!!

Anyone got any ideas about the theoretical rate of fire of a Luger going full-auto?

Whatever the fire rate, it's much too fast to be practical and can be very harmful to the pistol. TH

any chance for an explanation as to how the plunger works as an interrupt mechanism?

When the trigger is depressed, the trigger lever(in sideplate) pushes on the SIDE of the plunger which pivots the trigger bar (sear). When the pistol fires the cannon assembly including the trigger bar (sear) moves backward then forward to its original position at the completion of the cycle. If the trigger is still pulled, the trigger lever will be in the location that the plunger was before the trigger was pulled, so the plunger will be pushed into the trigger bar. When the trigger is released, the trigger lever will move back out of the way and the plunger will pop back out of the trigger bar, and will be in a position to fire again.

You may want to get a copy of â??Luger Mechanical Featuresâ?� it is a downloadable e-book written by a forum member that shows exactly how a luger works with text and animations. I found it on this site and it was most useful.

Hope this helps,

Chris

xlnt.....tks C