A number MP 41s have been made using a registered MP 40 tube with the MP 40 trunion installed.
Unfortunately, the MP 40 and MP 41 use 2 totally different methods to mount the barrel to the
receiver trunion and the resulting profile is distinctly different. This unit uses an original
MP 41 front sight assembly mounted on a barrel whose breech end has been configured to mate to an
MP 40 trunion. The barrel is retained with a nut which strongly resembles the flared collar
at the breech of an MP 41 barrel. It screws on to the MP 40 trunion using a pin spanner wrench
which is supplied with the barrel. The nut is captive to the barrel and cannot be removed without
removing the front sight assembly. While not 100% esthetically correct, it's appearance is much
more correct and pleasing than using a standard MP 40 "front end".
Click the images to enlarge them.
Pseudo MP 41 Barrel