Briefly submerged cartridge ammunition isn’t a big deal. The key to preservation under those circumstances is the crimp the casing has on the bullet. I can think of a few that would not do so well long-term, but I can’t think of any that wouldn’t be OK during a 3-minute exposure.
Smokeless powder will also burn wet. If the cartridge is filled with water, you might run into pressure problems, but it’s really no big deal. Primers will also work wet.
I imagine other than a really lengthy soak or some weird wildcat ammo with a loose crimp, you’re going to be fine. I know people who have fired 5.56mm, 9mm, and .45acp that has been underwater for weeks.
That statement had me down to the reloading room with a shot glass with water, and my favorite IMR powder.
I placed 35 grains in the water and swished it around for a while, then set up towels to drain the water away.
I then placed the damp powder on a dry sheet of towel and applied a match to it.
I had to leave the match on the powder for 15 seconds before the powder began to burn.
Yes it did burn, but I would not want to count on a cartridge firing with any kind of consistency, what I would expect if any would be a hang fire , and that in combination, a squib.(less energy less noise, less recoil than expected resulting in possible barrel obstruction)
As for the primer,
Primers are very well sealed. It has been an old legend that one should be very careful handling primer so that the oils on our hands do not degrade them to the point of rendering them duds.
Well Hello, I have soaked primers in penetration oil for weeks and they have detonated just fine.
All TBS, ammunition that is wet will possibly fire, and ammunition that was wet and then dried will most definitely fire.
Some ammunition, particularly in military calibers, is designed to resist water by having a sealant painted around the edge of the case and around the primer. The brass is also painted. That type will survive underwater for a long time.
I haven’t tried it with ignition by primer. A match has relatively low heat, and has to heat the water as well as the powder. I know it will go off instantly with a propane torch. Not sure about inside a cartridge, as that seems somewhat dangerous, and I don’t have any guns I want to risk blowing up
Did the powder burn normally after you ignited it? I think I have some nitro powder in the closet, I can do some experiments as well. No primers on hand, or a place to try primer+wet powder.
No the powder was slower to burn and I did not get the raise and fall of the burn like I was expecting. I have a couple other tests I would like to run and will get back to you on that.
I do fully realize that conditions inside the case are much different than open air tests.
I have had a good number of squib’s with 12 ga. steel shot in 4’s and 2’s over the years hunting ducks. sometimes the shot would land 20 feet from the boat.
These were factory loads, but the weather was cold and wet. My best guess would be when a the shotgun is unloaded and a shell drops and then gets mixed up with one that has been on the boat floor a week or two from another time one was dropped. Anyone that cannot understand that happening has never had a flock of bill’s buzz the decoys;)