Can you make the AR waterproof?  What happens if she gets flooded?

Waterproof like no entry whatsoever, or so that it can function after a swim?

If the former, I think it's close to impossible given the large seam seperating the upper and lower receivers. The magwell also complicates things.

If the latter, I think most any AR can function, you just have to open up the bolt afterwards to let the water drain out. The drier the works (esp. the barrel) the better. I don't know about salt water, though. There's a navy page about how to do it, but there's not really massive bodies of water around here, so I didn't look too hard.

Since I swim, shower and dive with my M16 on a regular basis here in Florida ... the drill is when you emerge from the water, elevate the barrel to 45 degrees, pull the charging handle back half-way and let the water drain out of the barrel and action. Firing will dry it as needed the rest of the way.

I've never taken the '16 below three atmospheres (90 feet below the surface) so I have no idea what extreme depths might do re: water intrusion in the cartridges.

We were taught at dive school (Special Forces Underwater Swimmer School) in the mid 70's, that the M-16A1 could be safely fired with water in the barrel.  Since the normal working depth for insertions was 30 feet, water penetration of the ammo was a non-issue.  When locking out of a sub at a greater depth, you normally rose immediatly to your swim depth.

No attempt to water proof the weapon was made and it didn't matter whether it was salt or fresh water.

All said, I'd prefer to drain the water from the barrel before firing, but operational conditions could preclude that.

HTH,

Omar

Waterproof? What for If you Lock the bolt to the rear under water and remove the magazine you should be able to leave the water point the barrel down for 2 seconds, insert the mag press the bolt release and go.

Firing underwater is supposedly a no-no The reciever explodes.  That could be easily remedied with some spring loaded steel doors in the lower to release water pressure.

[b]But I like to keep it dry (leave the Swimming to the SCUBA Hooahs and SEALs)[/b]

I heard if you submerge your rifle in sea water you should piss on it to rinse the salt off.

True?  I don't know, I just heard that.

Yes, it was the latter of the two.  I remember G.I.Jane when they were discussing "waterproofing" the M16.  It was stated that a condom over the end of the barrel would keep the water out.  That whole statment-as well as the movie is somewhat diturbing.

All the other times I've seen some mean looking dude rise out of the water with a M16/M4, the only thing he had hanging off the barrel were lights and lasers.

I am courious to find out how a gas tube full of water functions, though.

As always, thank you for the real world experience.

It wouldn't function very well. But as long as you don't unlock the bolt underwater or do anything else that will break the system's gas seals, you wouldn't get any water in it. The gas system is closed -- it must be for it to function and drive the action -- except for the port under the front sight tower. And water can't get in there because unless you REALLY work at it, fer instance by turning your weapon upside down and shaking it, the air is trapped inside and can't escape.

Water is heavier than air, and thus air rises (see the  bubbles?). Air cannot escape downward in water, and can't escape at all unless their is a way for water to flow in to replace the displaced air. A muzzle is plenty big enough for the air to rise out of it in bubbles and be displaced by water; same thing for the rest of the gun. But in those cases it will drain out as easily when you resurface. The gas system, though, will stay dry.

(Note to newbie divers here: Yes, when you get below one atmosphere -- 33 feet -- the air in the gas system will be compressed and there will be a slight water intrusion. But as soon as you return to the surface, the air will re-expand and expel the water in the gas tube.)

And yeah, I know you're supposed to be able to fire underwater. I haven't tried it. And if it doesn't break the weapon, you're still not going to have a very effective firearm: Water is so much more dense than air that the bullet will lose velocity and effectiveness in a matter of feet instead of hundreds of yards.

Underwater, I'll stick to spear guns.

I often wondered about the whole "condom" trick. I think it could be used in hard rain hiking situations, but for submersing I think it would be pointless.  Besides your wife might wanna know why the hell your taking a box of condoms on excursions.  Maybe someone can come up with an O-ring system for the upper and lower.

Nosler