is it possible to put a regular spurred hammer on a USP compact 45 and a set up the decocking lever to be like a 1911? cocked and locked with a single action only trigger?

thanks.

Quoted: is it possible to put a regular spurred hammer on a USP compact 45 and a set up the decocking lever to be like a 1911? cocked and locked with a single action only trigger? thanks.

You can't technically make it a single action (easily), but you can disable the decocker by installing a variant 9 control lever detent plate.  You can carry c&l with your standard variant 1, and many people do, but I like the idea of disabling the decocker myself.  Partly that is so I can ride the safety.

I recently shopped around for this detent plate for a USPf and USPc that I own and found that Numrich is the place to go -- they have them in stock, where most others do not.   Note that I gave you the URL for the fullsize -- detent plate is the same part for both fullsize and compact.  You want part #26 / item #603120, detent plate variant 9.

The detent plate only costs a few bucks and takes about 10 seconds to swap, with no tools needed.

As for the hammer -- I'm pretty sure you can replace that with the spurred hammer, but not 100% sure.  I'd like to know the answer myself, actually.  Not that it matters too much, as I really don't need to be able to reach the hammer -- the slide will cock it when I load the gun.  Plus you can pull back the bobbed hammer if you really need to.

The hammer is the same for both the full size and compact. I switched out the spurless hamer in my USP compact 45 for a spurred one no problem.

Quoted: The hammer is the same for both the full size and compact. I switched out the spurless hamer in my USP compact 45 for a spurred one no problem.

How hard is it to swap the hammer?  I'm guessing rather easy.

Yes, that is called a VARIANT 9 (10 left hand), safe only no decock, hammer with spur.  While it will not be SAO you can use it that way.  For conversion to SAO you will need to send it to Bruce Gray of Grayguns for one of his action jobs and conversion.
 FYI, the USP and the USPC use the same hammers so a spurred hammer can be added to any USPC or a bobbed hammer can be added to any USP.
To change the hammer it is very easy.  HK includes the bobbed hammer with the Expert and directions for swapping them out so even HK must not consider it too hard.

Quoted: Yes, that is called a VARIANT 9 (10 left hand), safe only no decock, hammer with spur.  While it will not be SAO you can use it that way.  For conversion to SAO you will need to send it to Bruce Gray of Grayguns for one of his action jobs and conversion.  FYI, the USP and the USPC use the same hammers so a spurred hammer can be added to any USPC or a bobbed hammer can be added to any USP. To change the hammer it is very easy.  HK includes the bobbed hammer with the Expert and directions for swapping them out so even HK must not consider it too hard.

Big-Bore:

Do you have a good URL with directions for the hammer swap?  I have a pretty good guess that you basically release tension on the hammer spring and punch out the hammer pin, but I'd like to know for sure.