Swap barrels in Bennelli B80 pistol?

[HisSoldier]

Not a common pistol in America, not real common even in Europe, so it's possible alterations may cost more later by degrading the supply for collectors.

These were made in five calibers, B76 in 9X19 Parabellum, B80 in 7.65 Parabellum and third in a less common caliber, 9 x 18 Ultra , and a fourth target related type MP3S in .32 long, and also a .32 ACP (B77).

It's said that the frame and magazines work for either the 9MM or the .30 Luger, which makes sense as the case is the same behind the bullet's base. It's possible that the slide is the same too, I don't know.

The .30 barrel is .550" diameter at the muzzle end, I don't know what the 9MM muzzles measure at.

The barrel looks to be pressed into the frame sub block, the frame itself is made of two halves of steel stampings welded together so well you wouldn't know it to look that they aren't milled, the inside of the trigger guard shows it though.

My friend says he has a new 9MM Bennelli barrel but that it needs to be reamed. That makes me think they are accounting for distortion during pressing by reaming later. There is one cut for a top mounted extractor, the chamber wall is only .060" approximately at that point and the larger frame extension it presses into is already slotted for the extractor, so needle files would do that nicely.

But my question is if anyone here has done this before? Most more common handguns have reams of info but info is sparse on this fine pistol. What is needed to do this? It must be something that can be done by a gunsmith or they wouldn't sell a replacement barrel would they?
Thanks in advance,

 

[Slopemeno]

What makes him think has barrel needs to be reamed? Has he shot it with normal, brass cased ammo, such as Winchester White Box?

 

[HisSoldier]

What makes him think has barrel needs to be reamed?

Thanks for your response,
He, like me as well, has a B80, which is the 7.65 P version. He simply said the replacement barrel in 9X19 isn't chambered, and since he is big into reloading for many years I expect he tried to insert a 9MM cartridge into the spare barrel.

Since I posted this last night I came upon another website which mentioned that CDNN had a sale in the late 90's or perhaps later which sent a new B80 with a replacement 9X19 Barrel, and I assume that is where he got it. I'll ask him.
Here is the rub, #1, how hard is it to remove the old barrel? And #2, (Assuming I'm right about why they came unchambered being related to distortion during pressing) Is it necessary to remove the sub frame from the sheet steel lower? If so how is that done?
But again, have any of you done this conversion? I'd kind of like to do it to mine as well.

 

[Slopemeno]

I don't think sending the barrel out to be chambered will effect your retirement posture.

I'd like to see a pic of the chamber end of the barrel. Perhaps this was for the Italian market, where military ammo like 9x19 is prohibited.

I searched, and I found an older post on another forum where the owner mentioned having an extra-unchambered barrel as well. His was missing the extractor cut.

We had a few of them pass through our shop on the 80's/90's, and they all seemed to function well.

I'd send the barrel to a place like Clark's in LA and pay to have it chambered. Give them a call and see if they've ever run into this before.

 

[HisSoldier]

I don't think sending the barrel out to be chambered will effect your retirement posture.

?
I'm "somewhat" retired, still have to work a little every day.

He has a 9X19 reamer, and as an experienced machinist this is not all that difficult for me to do. Now I know that the barrel is threaded, so distortion is probably not a factor, I can ream it in the lathe. I tried to download photos but photobucket is having troubles downloading today for me anyway.

One roadblock was detail stripping but I found my Gun Digest book on handgun disassembly and reassembly and indeed there is a section on this.
Getting the sub frame free was a minor roadblock, but it's clear now.

The extractor notch needs to be cut, the face of the barrel must be flush with the breech end of the sub frame and the ramp must be cut as well.
If he decides to do it I'll come back with results. I would like to buy a barrel for mine as well. One thing, the top of the breech is stamped "7.65" so I'm not sure if that's a legal thing that needs to be changed. I can hand engrave it if it is.

 

[Slopemeno]

'Jes kidding around about your comment with regard to "collectors". I.e-it probably won't affect the value that much.

 

[DT Guy]

I've got a B76 I bought about 33 years ago. Great gun, great shooter, but slide bites like a demon.

AFA the caliber markings, even if not required by law, I'd think that was a simple safety issue; I'd never work on a gun that ended up mis-marked in that way.

Love to see pix when you're done-


Larry