well this thread is a little old but I figure its not old enough for me not to put my imput in it. I have personally Hit targets 110 Yards out with my KWA SR-12. (accurate by the way, not just floatin' them) But with KWA their gearbox is built around the internals, hints why you dont have to shim the gears. The air seal stock is NEAR perfect, again it was built to be this way. (If any of you have worked on these guns and analyzed these you will understand where Im coming from) When I first bought the rifle is shot 420 w/ a .2 gram bb and shot accurately out to about 70 yards. But with the new 2GX gearboxes the gears can take just about any spring on the market. After having the gun for about 2 months I decided it was time to start messing around with the Interals.
First Impressions, is that the rifle took a Modify 130 spring stock NO PROBLEM.
Next test was a Modify 140 spring (these hit 500 FPS w/ .2's and took me $400 to get my CA to shoot that), and again shot with no problem on stock everything, and straight none-the-less.
ANNNDD NEXT: Modify 150 spring. Motor started to run very slow and eventually fuse busted, no matter though I was expecting it. So after removing the fuse and Wiring to deans connectors I switch the motor to a G&P 160 motor (very high tourqe and FAST) After that the guns internals had no problem with the 150 spring at all and still shot fairly straight (I had seen better accuracy though)
Before I go on, these tests were done with over 8,000 rounds per spring and no problems at all. And as for the hop up; it held up very solidly against the high springs and just recently has really started to wear. (The 2GX buckings can be bought from KWA for around $12.00)
On to the final test: This test was done with ALL STOCK PARTS EXCEPT THE MOTOR. Spring used was a System 165 spring (this hit 625 FPS w/ .2's) Shot for a good while, I'd say 2,000 rounds until the piston finally gave out. So I switched that out for a King Arms POM hard and it was back up in no time. At this point accuracy with the stock barrel was absolute garbage and I couldn't hit a 70 yard shot if my life depended on it. So after a quick barrel swap to a Promy 6.03 TBB it shot great! Using .36g bbs it shot straight and very fast. It still has this setup and everything is looking like new. No gear wear what so ever. (Nashville Airsoft did a test when the 2G KWAs came out and they put a 140 spring in one and it shot over 100,000 shots and I still dont think its gone down)
RATE OF FIRE RESULTS: (Disclaimer: This gun was used in semi only (w/ the 165 spring) when fielded abiding my fields DMR restrictions and was used on auto with the 130, 140, & 150 spring, again abiding rules)
All tests done with Tenergy 9.6v 4200mAh battery unless otherwise stated:
(After the stock reading I did the following tests with the G&P motor)
Stock: 22 RPS @ 420 FPS
130 Spring: 22 RPS @ 455 FPS
140 Spring: 21 RPS @ 505 FPS
150 Spring: 19 RPS @ 545 FPS
165 Spring: 9.6v: 17 RPS @ 620 FPS
11.1v Li-Po: 22 RPS @ 620 FPS
12v Ni-Mh: 25 RPS @ 620 FPS
14.8v Li-Po: 30 RPS @ 620 FPS
Now for the people that want a cheap DMR build. The New 2GX KWA's will take a variety of springs and you will not have to invest in those $100 gears. Barrel, motor, piston: thats it, and you can have a gun thats capable of shooting 100+ yards and do it accurately. I hope this helped alot of people out there thinking of a KWA as a base gun. I hated the 2008-09 KWA and ended up redoing my old one to a high speed setup shooting in the mid 40s RPS and I was pretty skepticle of buying the '10s but it was one of the single greatest airsoft investments I've ever made. These guns eliminate the need for the $400-600 upgrades, and cut it down to $200. If you have any questions feel free to ask!