I use a DMR rifle myself and its fixed to fire in semi only and I find that a 0.3g BB traveling at 307fps has sufficient energy to punch through pretty much anything on any of my local fields. For an average load out I only carry 6-10 TM 68rnd magazines. I used to carry 18-24 but for the amount I carried I never used them all in a full days play, plus it was a pain to carry a full dump pouch full of empties. Now I carry a reduced load and usually have to reload my 6-8 mags at least once or twice during a 8-10 hour days play.
"Its only a little bit on fire"