I only know Hedgehog really....Nope.
It was an attempt to create a spigot mortar weapon that could be mounted in smaller craft, or on larger craft without replacing one of the 4" guns. As you know, FIxed Spigot weapons generate a lot of recoil. If you had fitted a hedgehog to a small craft you'd only get one shot as the hedgehog would have put itself through the deck. It was pretty close on the Flower class as is.
These ones were mounted hanging over the side of the boat to use the ocean as a water buffer to absorb the recoil.
Correct, it was a trail weapon, fired off a pier if memory serves.I only know Hedgehog really....
However, on a more serious note I assume the presence of the "recording pin" indicates a weapon under development rather than being a part of normal operation. Presumably they sat on some sort of float? If not how was the recoil force dissipated?
It may have been the pier at Weston-super-Mare: see chapter after this sentence. Was it called a 'water hammer' recoil absorption method? The Wheezers & DodgersCorrect, it was a trail weapon, fired off a pier if memory serves.
As to operation, think if you will, of what would happen if you replaced a rifle (standing in for our spigot and a source of recoil) stock with a sink plunger, then mounted the entire contraption to a really big spring. The spring is attached to something solid, such as a boat.
When the rifle is fired, the entire contraption compresses the stationary spring, and the sink plunger slams into the water, which acts as a break on the round head.
Once the water has absorbed the recoil, the spring returns it into battery.
I'll get my gauge out and measure it for you. Here is a shortly to be available PIAT (I hope).A ridiculously simple question... What's the calibre of a PIAT?
Note: Calibre in this case would be the spigot width, not bomb width.