I need a good gun to put an ACOG scope on in MW2?

Ok... I like ACRs and UMP45s. I have an ACR with a grenade launcher and holographic sight, an ACR with ACOG scope and grenade launcher, and a UMP45 with red dot sight. I want a quick grenade launcher with red dot sight or holographic... but I also want one with an ACOG. What should I do?