I seem to have accumulated a number of early military 22s and I'd love to add one of those to my collection. But as a former USN mineman, and one who has talked "mines & minesweeping" with my late uncle, a coxswain in the "Yankee Mining Squadron" who shot at a lot of mines in the North Sea back in 1919, I have some doubts about the ability of a 22LR to detonate or sink a floating mine in a manner that does not endanger the shooter and the vessel he's shooting from. Most WW1 naval mines were spheres about 30" to 36" in diameter. They were made from pressed steel sheet metal about 1/4" thick. Would a 22LR penetrate? I doubt it. So you must shoot at the "horns" or external triggers. There will probably be 4 or 5 above water when the mine is floating, but no more than 3 will be visible. Each is about the size of a large light bulb. The bullet has to hit hard enough to throw a spring-loaded switch or to punch through a lead bottle and break a glass vial. To do that with a 22LR from a moving platform while shooting offhand at a moving target, you would have to be really close. The mines all contained about 300 lbs of TNT. That's a big bang. Minesweeping vessels & the crew got knocked about when the mines went off. Interior spaces were frequently padded with mattresses & blankets. Crewmen with critical inside jobs (helmsmen, enginemen) sometimes wore football or hockey players' helmets & pads. The best snap shooters on the crew would try to set the mines off at 50 or 100 yards or further, standing on deck and shooting offhand. The USN shot at floating mines with Springfields, even in the 1960s. The RCN would have used their Ross rifles, but in 303. Semi-autos were an unnecessary safety hazard. If shooter & rifle get knocked over because the mine you just exploded set off another one, a loaded rifle just adds to the problems.
