I just last night bought a 712 on gunbroker. I was wondering if you could swap out the barrel assembly with a 9mm broomhandle . i have two 9mm and have lots of 9mm that i have reloaded ,the 714 is 30 cal mauser,just a thought.

They'e both hand fitted so it's a roll of the dice. Assuming they fit together, a couple of things to consider:
1. Get a 9mm magazine follower; it's got a little scallop on the lower shelf, to handle the shorter 9mm case. They're the follower you'll find in the 'Red 9' Mausers.
2. The bolt is light and comes back fast. Get a new bolt return spring, the spring around the firing pin. I'd recommend the Woolf 'extra power' spring, as the 9mm develops more recoil and you don't want the bolt stop peening the back of the barrel extension.

I have all that new springs correct mag follower correct sights, but one is full and one is semi.it would be cheaper shooting 9mm. have never had a 712 in my hands before. my question could i just swap out barrel frame assembly for lack of better words and it operate ?

My knowledge of Schnellfeuers is pretty scanty. I think something in the bolt trips the sear as the bolt closes. That prevents firing before things are locked. Look at your 712 bolt, particularly the underside, and see if it differs from the semi auto bolt. Work the action in full auto mode and see what causes the sear to trip the hammer. You may have to use your 712 bolt in the 9mm assembly to getr full auto fire in 9mm.

I guess that will have to wait until it get the form 4 back from atf. just something i was thinking about.

I guess that some folks march to a different drummer than I do.
If I had just dropped 10 Grand (plus extras) on a gun, I wouldn't be trying to make it do something it wasn't designed for......
(But that's just me.)

__________________
Dean
SWCA #680 SWHF #446

My C 96 is in 30 Mauser still and I bought a can of Chinese ammo about the same time (It came from China, I figured it had used that ammo before). It still works so don't fix it. Ivan

Just placed a order with midway for brass and bullets .guess i will load a bunch while waiting. in 2011 the wait was only about less than 2 months for a mp44

Somehing just occured to me: The barrel extension on the 712 is a lot thicker than a semi-auto Mauser, partly to give added strength and partly to slow down the action a little. A 9mm produces more recoil than the 7.63mm; you probably don't want to shoot a stronger recoiling cartridge in a frame that is weaker than the full auto design.

A 712!!! I'm envious as hell.