I have a 4006 that I fitted a 5906 slide and barrel to about 10 years ago to go with my 411 that I fitted a 5904 slide to also and it was nice being able to fire both calibers out of the same pistol. Recently I decided to rechamber a spare 9mm barrel to 357 Sig caliber and use it on the 4006 frame.

It was not that difficult to do but it requires opening up the breach face to accommodate the 357 Sig. The ejector works and I have installed a 20 lb recoil spring which is what the Sig pistol uses.

You can still use the 9mm barrel so it is now a three caliber pistol.

I just received the recoil spring today and plan on test firing it this week so I will keep you posted.

Pictures Man, Pictures. Please.

Smith 3913 Chambered in .357 Sig (pics)

it does not look any different than a 4006 or 5906. I did manage to fire it today and it shoots very well. There is quite a bit more noise which I expected and the 20 lb spring dampens the recoil to the point that it's hard to tell the difference between the three calibers.

I am always fascinated by these conversions.

How did you open up the breach face?

John

Can this be done with TSWs as well? I'd love to pick up a CHP 4006TSW and put a 9mm slide/barrel on it. I assume I'd have to pick up a TSW upper assembly rather than a standard upper.

I opened up the breach face with a reamer and a file. There are two hood diameters I have large and a small. I opened up the large so it doesn't require that much metal removed. I would not suggest opening up a small hood slide unless you have access to a machine shop.

I don't know if the TSW can be modified. The slides on both of my conversions interchange it's the lug on the bottom of the barrel that has to be narrowed to fit the 40 caliber frame. I did both with a hand file and plenty of patience. Once I found the center and how much I had to remove it was just a matter of taking the same off of each side.

One thing that is interesting is that before I rechambered the 9mm barrel to 357 Sig it never shot as well as the 411/5904 conversion I did earlier. After the rechambering the new caliber shoots smaller groups than I shot before with 9mm ammo out of the same barrel. Maybe the increased velocity made the difference.