check this out

[DieFamilyGuy]

while playing today, i found something very interesting.

if you hold down the charge shot button with the lucifer cannon, and then press normal shot, you won't use any ammo.
it really only works with 1 bullet left. im suspecting its a glitch

[Snarboo]

Yeah, definite bug.

[b0rsuk]

Another (minor) bug:

Normal credit limit for marines is 2000. But you can get more if you sell your gear. I think in such case money should slowly decay until it reaches 2000.