Originally Posted by Snausage
I think the DAM is the most feature-rich marker in this category. You can load a magazine with up to 20 first strike rounds (10+10), which is unique to that marker as far as I know.
Any DMAG equipped gun that supports first strike is capable of this. 468, T68, MK5 w/ FSR Bolt, etc. the DMAGs are similar to the DAM mags in that they are double stacks.