A guy on a hawaii spearfishing FB page posted this just happened. He got sand in his mech on the way out and shaft didn't lock in all the way but well enough to load. He was holding the gun half way up the stock and the spear shot out; the pins did this to his hand.. anyway just a heads up especially for shore-divers.
Dan and I used to have a helpful chant we would do along the beach, "keep your sh!t out of the sand, out of the sand"