Yes, they do look excessive, but steady and stable are the keys to successive machine gunning. I don't remember ever feeling unsecure firing off either the Jeep mount.
The tubes are at least 2" heavy wall steel, with ball detent plunger-type locking pins. The recoil of a 7.62 MG is not insignificant, nor are the forces of a 20lb gun out shaking on the end of a long mounting arm. During firing the pistol grip as the only place to hold on, so a solid mount makes sense.
The Lynx recce vehicle had a slightly different version of this mount, with a diagonal elevation lock (?) coming up from the post to the rear of the mount. The M38A1 jeep version had no such fixture because of the shape of the vehicle.
Thanks for the photos Rob.
At the OMVA gathering, a fellow in the Friends of the War Museum off-handled said he had the technical papers for the jeep mount and wire cutter. A next year project for me.
