Double Naught Spy
Sus Venator
"Howdy" comes from "How do you do?" by way of "Howd'ya do?"
And "Howd'ya do?" comes from "How do you do?" assuming we are speaking of the greeting and not asking a shooter how well they just finished the last stage they shot in a match. "Well Jim, Howd'yado?" to which Jim says, "I shot great!"
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Would not a 50 BMG pistol, though, ban the ammo for it (at least in the USA) as 'armor piercing'?
No. There are .50 BMG pistols, but I don't know anyone who has shot them.
For guns such at a Thompson Center Arms Contender, you can get any manner of rifle caliber barrels such as .308, .30-06, etc. for which there is AP ammo available.