[Gattaca]

I know this has been discussed before, specifically here https://www.waltherforums.com/forum/p99/62834-threaded-ppq-barrel-p99.html but the post was a bit confusing.

I'd like to snag an M1 and slap the Q4 Tac slide on the M1 frame. I'm also interested in swapping the M1 non threaded barrel into the Q4 slide, but I'm not sure that can be done according to that post. If both guns are new, would I be able to interchange the barrels? The M1 also has noticeable changes in the slide based off of this photo

, is it still drop-safe on different frames?

 

[imaoldfart]

I think the key may be the serial number/s. If both pistols have a serial number higher than FCA 0001, I think you'll be OK.

 

[Gattaca]

I'll write it down and do some comparisons when I go to a gun show here in a couple weeks. I saw your reference to that serial number on that post but just wasn't sure.

 

[SpaceGunner]

The serial number issue has to do with barrel to slide fit. The frame makes no difference. Make sure that the barrel and slide numbers are both either pre FCA0001 or post FCA0001 and you'll be fine. Don't worry about the frame.