Putting gun in water to find leaks

“My” gun can be immersed in water if looking for leaks, even with the stock intact … but I DO remove the gripframe, which contains the trigger group and the hammer spring usually comes with it, as some parts in it can rust. The barrel could rust if left alone, but I usually just fire it a few times after to blast moisture out. 

I designed the gun to allow for this, and so far I’ve seen no issues in over 15 years.

I think I misunderstood the post. I never pun water INSIDE my gun to find leaks (if that was meant to read that way). I immerse the gun in water, preferably hot water, first the muzzle end, looking for bubbles be sure to close the bolt so a leaking firing valve bubble out the muzzle, then the breech end.