H&K USP9f question

[CabinJohn]

A friend of mine just acquired an H&K USP9 full size, and now has a couple of questions:
I have a USP 9mm pistol that was manufactured in 1994. There were two upgrades in late 94 that my pistol does not have. They are.
1. A self contained recoil spring on the guide rod.
2. A Polygonal barrel.

The questions are - Do you recommend an upgrade? Why? And by whom or where to order parts?

Thanks for any good input.

 

[Hammerhead]

I don't think there is a need to upgrade.
hkpartsonline.com is one of the few places to get parts for USP's. I guess the recoil spring assembly would be worthwhile if the pistol has a lot of rounds through it.

 

[silver-bullet]

Those "upgrades" are not essential to the function of your weapon. The standard rifling is actually better than the polygonal for cast bullets, and the old style (open-ended) recoil spring makes routine replacement of the spring itself MUCH simpler. If you are concerned about the spring-tension, you can purchase replacement springs from Wolff, at:

www.midwayusa.com

I think they run about 8 bucks. The factory recoil-spring weight (by the way) is 13 pounds (9mm).