Post
by bam » 20 Jul 2019 11:45
I read that the rod was Also to help hold the extra muzzle brake on.
The original aircraft mounted 30mm mk103 had a flash muzzle on it with 7 perpendicular holes each side. It was purely for dispersing the powerful exhaust gases safely, it wasn't a brake, it was for splitting the exhaust up into smaller jets to prevent damage to the body of the aircraft.
When they tried putting the mk103 30mm on the 20mm flak 38 carriage, they found the recoil forces were overloading the carriage. So Hptm. Seherr-Thoss at Sagan improvised a muzzle brake. That's why you only see the rod on barrels in the 103/38 mount, where recoil was the main problem. It is best visible on the surrendered carriages in post#91.
It was simple, small angled plates, that deflected the sideways moving exhaust-jets (from the holes in the flash-muzzle), into a backwards direction, thus reducing recoil. To help anchor this fixture and prevent it being blown off, they added the rod, securing the brake to the barrel-base area. They also filled some of the voids in the carriage base with concrete and scrap metal, to add mass to the lafette to stop the whole thing jumping about when fired.
The problem with the 103/38 was they were now firing a 330g shells on a lafette built for 120g shells, and the carriage was basically too light. This lead to stability problems when firing at full auto. It was an expedient design, not a good design.
If the rod improved accuracy, surely it would be seen on mk103's that are mounted on carriages other than the flak 38; e.g. the improvised wood posts. Are there images of rodded mk103's on timber posts?