Along with rifles and semi auto handguns, revolvers can absolutely be suppressed. NY and NJ have been doing it for years. 

The USAF bought quite a few Model 39s in the 1960s and 1970s because it became the pistol they issued to General Officers. They did not issue them otherwise. Their standard side arm with the 4-inch Model 15 starting in 1962.To my knowledge as well, SEAL teams (and possibly other SOF) were the only unit(s) issued M39s in the VN era.
I wasn't aware of the modifications that changed them to MK22 Mod0 .22LR. I thought they had remained 9MM. I guess given the "tunnel rat" scenario that makes sense, but you say that was an exclusively Army mission. Learn something new every day.
So two questions:
1) What did that mod wind up increasing the magazine capacity to, 10 or 12?
2) Did that make the resulting MK22 Mod0 subsonic pretty much solely an up close and personal assassination/execution weapon?
I did know a Marine who claimed to have been a tunnel rat, but he never mentioned what weapon he used. I simply assumed it was the standard issue .45 (possibly suppressed as that would have been best for that mission). But it sounds like you're claiming he was full of it…which I guess was a possibility.No, sorry, not true. The only VN era pistol with a suppressor and slide lock was the MK 22 MOD 0 (based on the S&W Model 39-2) and it was used exclusively by the SEAL teams. The so-called tunnel rats were Army and lots of guns were tried and a number of experimental models were proposed by the Army's Natick Labs and ACTIV group but none were very successful.
Now that IS what I believed from the outset (though I didn't know the change made them MK22Mod0s), thought they would have just called them a different-.The USAF bought quite a few Model 39s in the 1960s and 1970s because it became the pistol they issued to General Officers. They did not issue them otherwise. Their standard side arm with the 4-inch Model 15 starting in 1962.
The USN bought hundreds of Model 39s to issue to the SEAL Teams and officers that requested them.
The MK 22 MOD 0 was a modification of the Model 39-2. It was 9mm and used standard magazines. The modifications were 1.) a suppressor system; 2.) a slide lock so that the action did not cycle; 3.) subsonic ammo; 4.) various plugs and caps to keep water out of the pistol. There were only about 110 of them made and they were exclusively a SEAL weapon.
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