Welp, I have now decided to join the trend of build and setup threads. I have seen many people starting threads asking how to achieve certain performance goals, and maybe this can serve as a source of information and inspiration for people with less experience with tech work. I'll post both finished and unfinished projects, some with short video clips with test runs. I'll start off with my trusty little CYMA MP5K, it's been built specifically for CQB use, hence the relatively low power. The reason for the relatively high spring strength is to make semi auto crisper, and it also makes it hilariously loud.: CYMA MP5K Gearbox: Stock CYMA 7mm GB shell with Element smooth steel bushings. Dream Army (SHS) 15T piston, swissed, glued teeth rack and 2nd and 3rd tooth removed for AOE correction. Lonex POM piston head. Lonex steel bearing spring guide. ASG Ultimate M130 spring, power reduced to .95J with inversed power creep, didn't feel like short stroking another gear. SHS 1st gen 13:1 ratio gears, shimmed by the bevel, of course. Lonex air nozzle and cylinder head. Lonex tappet plate, front sanded for improved consistency. Stock trigger and cut-off, trigger return spring tightened for more effective cut-off. Dream Army (SHS) Ultra Torque motor. Barrel and hop-up: Polished TM 140mm barrel, from my old TM MP5K, properly stabilized. Stock hop-up chamber. Guarder clear bucking. Electrical: 18AWG silicone wire with HK XT Deans clone connector. It only does 33rps, low for a setup like this, this is because of the relatively high resistance in the wiring. (will probably upgrade with 16AWG or 14AWG teflon wire) DIY IRLB3034 based mosfet unit, with 45 amp PTC fuse. (it's 45 amps because I initially planned a much more elaborate setup) Turnigy 11.1V 40-80C 1400mAh li-po, used a Firefox 11.1V 20-25C 1200mAh li-po before, but it was too underpowered for this setup. Accessories and magazines: G&P MP5 type red dot sight. CYMA 100rd and 65rd magazines. Pantac one point bungee sling. PDW flash hider from my old TM MP5K Here's the internal setup of my AK that I will most likely stick to. I'm ditching that high speed motor, it pulls too many amps for it to be practical, I'd have to heavily upgrade the wiring and battery, and install an even higher rated fuse to run it properly. I may do a test run with the high torque motor with a 14.8V li-po, just to see how the GB fares, I like to experiment a bit hehe. G&G AK-104 Gearbox ASG Ultimate M130 spring VFC 8mm GB shell with G&P bearings Deep Fire bearing spring guide DA 15T piston,heavily swissed, teeth rack glued, 2nd and 3rd tooth removed for AOE correction. Lonex POM piston head Lonex cylinder head DA double o-ring air nozzle SHS 3rd gen 13:1 ratio gears, with 2 teeth short stroke. DA Ultra Torque motor Lonex cut-off lever, trigger switch and cut-off has been tuned for the cut-off to react faster. Electrical It has an IRLB3034 based DIY mosfet unit, with 36A PTC fuse, and a mix of 16 and 18 AWG wiring, because of the cramped motor grip. I currently run it with my Turnigy Nanotech 11.1V 40-80C 1400mAh li-po's, but I'm thinking of maybe getting something a bit beefier, since the stock has room for it. Barrel and hop-up Stock G&G 360mm barrel, polished and stabilized CYMA AK hop-up chamber with Guarder clear bucking It does approx. 38rps at 1.3 joules with this setup, the power is a bit low because it doesn't have a tightbore barrel, and the cylinder volume could probably be more optimal. The power is very consistent though, and 1.3 joules is perfect for my needs really. It also has more than enough range for the field I play at, with decent accuracy, so I'm overall very pleased with this setup. Here's my take on the SAW class of AEG's, it's not quite a true SAW though, too inefficient and too high stress on the internals. I did it more for the technical challenge of it, it's practical use is limited due to field regulations. It was still a fun build though, and made one of the AK purists at my local field get all giggly when he test fired it hehe. It does 33rps at 2.1 joules.: LCT RPK Gearbox LCT 6mm GB shell, with stock steel bushings. LCT compression parts (the stock compression parts are actually very high quality). Lonex M150 spring. DA 15T piston, 2nd and 3rd tooth removed for AOE correction, teeth rack glued with HK Maxicure CA. SHS 3rd gen 13:1 ratio gears, shimmed by the bevel, standard procedure. Element bearing spring guide. SHS Ultra Torque motor. Electrical HK 16AWG silicone wiring. HK "Deans" contacts. IRLB3034 based DIY mosfet unit. 3x15A PTC fuse. Turnigy Nanotech 11.1V 40-80C 1400mAh li-po battery. Barrel and hop-up LCT 605mm barrel. Guarder clear hop-up bucking.