The drawback of the roller-delayed system in a submachine gun is that ... In 2014, on the 50th anniversary of the MP5’s debut, H&K introduced upgrades to the design it called a “Mid-Life ...

In H&K roller-delayed firearms that tube above the barrel houses a rod that moves the bolt when pulled to the rear (remember there’s no gas system running in that tube). It’s not connected to ...

The HK SP5 is really the only pistol worth ... and it even includes ½ x 28 threads for doing so. Thanks to the roller delayed blowback operating system, the SP5’s recoil impulse is very smooth.

Here’s What You Need To Remember: H&K brings the most mechanically up-to-date revision of the MP5 to civilians in the ... Internally, the MP5F locking roller holder is used, as well as the ...