The lowly .22 caliber long rifle round is becoming a favorite among snipers. Professional assassins (usually thugs working for organized crime) have long favored using .22 caliber (5.56mm) pistols for their work. While not a powerful round, if you shoot someone up close with a .22 caliber pistol several things are noted.
The original 1973 movie version of Day of the Jackal (remade as The Jackal, with Bruce Willis) had a very professional assassin using a specially made single shot 22 rifle. He hand drilled the bullets and filled them with mercury and then capped it with a putty to hold the mercury in place.
1- The victim is dead if you shoot him in the head, which is what pros usually aim for (as these guys like to say, "two in the head and you know he's dead.")
He practiced with a watermelon as a target and regular 22 bullets first. He'd hit it dead on and get a nice neat hole. Then he switched to the mercury loads and poof - no more watermelon.
Interesting movie, but it was most interesting to me for the portrayal of stuff like this. The guy playing the assassin (Edward Fox) was a cold blooded SOB who didn't look it. That's what's really frightening. Remember Wednesday Adam's line from the first Adams Family movie about her apparently not wearing a Halloween costume? "I'm going as a serial killer. They look like everyone else."
2- There is hardly any sound if you use a silencer, and not much even if you don't.
In the book and first movie his target was De Gaulle at ceremonies in Paris. The silenced gun was so effective that he was able to miss once or twice and no one noticed it.
3-A 22 caliber pistol is small, even with a silencer. That makes it easier to conceal, and easier to dispose of.
The gun broke down into pieces that fit into the aluminum tubes of crutches. The butt plate was obviously one of the pads on the top of the crutches. He folded one leg up (rather painfully) to make it look like he was an amputee and used that ruse to get past the guards to a vantage point overlooking the square.
I never though the same about "little" 22s since then. Someone else pointed out to me once that a 22 is bigger around than an ice pick and you wouldn't want that being introduced into your body, even without much relative speed.