American Armament ordnance is always in high demand by US collectors, with unusual designs and history, much of which is not easy to find. I have a number of the mortars and have had a few of the 37mm AT gun cartridges, but recently picked up a variation that is a little unusual.
In the first photo is the standard 37x178R and a spare projectile. In the second photo is another AA case that I recently obtained. This case is headstamped the same, but instead of 37mm it measures approximately 41mm (very slightly belled case mouth). With the same headstamp it looks to be an experimental case, but I've never heard of them doing anything of this sort. Thoughts?
In the first photo is the standard 37x178R and a spare projectile. In the second photo is another AA case that I recently obtained. This case is headstamped the same, but instead of 37mm it measures approximately 41mm (very slightly belled case mouth). With the same headstamp it looks to be an experimental case, but I've never heard of them doing anything of this sort. Thoughts?