Gun trivia
 

Well use the honor system on this. Dont go look it up on the internet. Then your a tool.

First to guess correct posts the next.

Question:

What is the u.s. military's longest serving cartridge still in use today?

It can be something specialized, like if you want to put .30-06 since its used in the national matches, go ahead. (hint, its not the -06)

Perhaps it is .50 BMG?

no, but 50 is the longest serving standardized round i think, since it is still mass issued. Im thinking of a more obscure round. may give hints later.

Pistol or rifle caliber?

rifle

obligatory10

.308 - 7.62x51

no, thats been serving even less than the -06 or .45acp.

.38 Special?

I'd go with the .38 as well.

its a rifle round, hint: primary user, U.S. Navy.