[DCP]

Does the USC Trigger group fit in UMP NAVY OR FBI LOWER?

With or without any Modification to the lower?
Thanks

 

[Jeff Smith]

Parts Drop right in.

 

[AviatorDave]

Parts Drop right in.

Not on the UMP lower I bought. They will, but not without modification. There is a plastic wall at the very back of the lower. On the USC lower, there is a cutout there where the disconnector lever fits so it won't fire if the bolt isn't fully closed. On the UMP lower, it is a solid wall that will have to be cut out.

Edit: And... now I know why. Aparently I bought an "old style" lower that needs more mods than the "new style" one. Damnit.

 

[Jeff Smith]

And... now I know why. Aparently I bought an "old style" lower that needs more mods than the "new style" one. Damnit.

You are correct.