Which Rifle should I use?

Sig550
or
HK MSG-9

Don't factor in pricing or upkeep cost at all.

It should also be known that I'll be carrying an HK-UMP SMG at the same time.

which one is better

Well I don't know which one that is, which is why this thread exists.

The SIG has a larger rifle requirement, ammo capacity, and shoots faster, but does less damage than the MSG.

I figured if I wanted to shoot faster for less damage, I'd just use my SMG, which is why I'm leaning towards the HK MSG.

But I figured I'd get some opinions from people who've used both guns before I made the switch.

SIG 550 has a higher DPS.

It also shoots faster, so it will handle more zombies before you have to switch to your HK UMP, letting you save more ammo on your UMP.

I'd go with the SIG 550.

Alright, thank you for clearing that up. ^_^