Here’s something that’s probably not well known. The T114 tank destroyer. It was built on the T114 APC chassis. The T114 came in service as the M114 AFV and was used in the Vietnam war, where it proved to be a disaster and was relatively soon pulled from service.
This is a project to actually mount a turret with a 106mm recoilless gun with automatic loading from a magazine on the right side of the gun. An interesting design by any means. The British experimented with autoloading recoilless guns as well, although they used drum loaders to feed them.
This prototype was apparently developed between 1957 and 1960.