Converting an old KSC USP to a NS2 (system7) USP

[crackisbad]

So I had an old USP and wanted to upgrade it but all the upgrades that I found are only for the newer NS2 USPs. After seeing all the topics about the similarities between the two USPs, I decided to see what I could do about just converting my USP. Originally I was just going to swap out parts, but I found a really cheap NS2 USP and decided to just buy that because I was having trouble finding a barrel assembly. BTW: Nearly all the parts I needed to convert (except for the barrel assembly) I found on KWA USA's shop online.

 

On to pics:

Black is old USP and Silver is the NS2.

 

 

Old is left, NS2 is right:

 

 

The blow back unit appears to be the same and the only difference looks to be the loading nozzle, which is easily changeable (metal is old, plastic is NS2)

 

 

Here is where I ran into the first issue: the NS2 slide has additional crescent-shaped material that looks like it keeps the NS2 loading nozzle centered and the slide has a slot in it:

 

 

Easily fixable, i took a set of needle files and cut a slot in the old slide (the silver portion after the opening on the left slide) It remains to be seen if the absence of the additional crescent-shaped material will affect how the NS2 loading nozzle lines up:

 

 

I was hoping that I could use my old outer barrel if I just took a dremel to it and created the slot in the middle:

 

 

Here it is all swapped! The set on the left is the old USP with the NS2 guts and on the right is the NS2 USP with the old guts:

 

 

All put back together! The silver USP now has the old guts and the Black one has the NS2 guts

 

 

 

Coming up next is converting the Magazines to work in with the NS2 guts!

 

 

The whole thing took about 30 minutes and was probably one of the easiest things I've ever done for airsoft