Excessive detail time. I'm not sure what the mecha_to_identify tag is referring to, but hopefully this covers it.

Main picture:
M4A1 w/ LMT/B5 SOPMOD stock, Aimpoint T-1 on LaRue LT660 mount, KAC 600m BUIS, AN/PEQ-15, Grip-Pod, 5.56mm Magpul
Beretta 92 variant in Blackhawk SERPA dropleg holster

Inserts, left-right/top-bottom:
Ruger Mk.III Standard w/ C-More reflex sight

AR-15 variant w/ Noveske-marked lower, Noveske NSR rail, EOTech 512/552, Magpul MIAD/MOE pistol grip and (pre-M3) PMAG
what looks like a SIG P22x

IMI Uzi w/ fixed stock

HK MP5KA4 w/ Navy trigger pack, drum magazine

Harris Falcon III (AN/PRC-152) radio

Steyr AUG A2 w/ 16" barrel, Leupold Mk.4 CQ/T telescopic sight, Surefire M951V/M952V
full-size or compact gen.3 Glock in Blackhawk SERPA dropleg holster

FN Mk.46 Mod 0 w/ AN/PEQ-15, vertical foregrip, 100-round belt box in AOR2

Glock 18/18C gen.3 w/ extended magazine, micro reflex sight, Insight M6X light/laser

railed, single-stack M1911 variant w/ Surefire X200/X300 feeding jacketed hollowpoints, apparently steel-cased

AR-15 variant w/ pink Magpul MOE stock and back-up iron sight (??)
compact or subcompact gen.3 Glock in Kydex holster

(gear: Mil-Spec Monkey hat, LBT-6094 plate carrier, Oakley SI gloves, Arc'teryx kneepads; Mechanix gloves in insert 6)