TorkMag has AR magazines in 35 and 50-round capacity! By using dual springs and a rolling follower TorkMag manages to cram extra rounds into magazines only slightly larger than a normal mag. The 35-rounder will still fit in most magazine pouches and those extra five rounds can make a difference.
If you needed more ammo would you rather squeeze the trigger once more or reload? The 50-round magazine is indeed approaching monopod length. Time will tell if this dual-spring system and polymer body can hold up to the pressure. Have you tried a TorkMag? If so let us know in the comment section below.