Nowadays, more and more AEGs are coming out with the quick spring change feature, allowing you to meet airsoft field requirements in terms of FPS limits. Still, there are many AEGs with gearboxes that still require the good old fashioned way of changing springs, which means it is also the hard way. Here is Airsoft GI Uncut showing you which is good for newbies and for veterans who have forgotten how.
Evike.com demonstrates the True Quick Spring Change System feature of the upcoming Krytac KRISS Vector AEG which they have on pre-order again... "Who remembers when Quick Change Springs meant disassembling half your gun?! Tag a friend who lives under a ROCK and NEEDS to see this!!!
One of the COOLEST features of the soon-to-be-released Krytac Kriss Vector AEG is its TRUE Quick Change Spring System. 2 pins, and you're swapping springs.
ICS Airsoft do have a unique gearbox amongst other AEG manufacturers, and they have their own Split Gearbox techology which has been available for many years now and has evolved into the Transform4 gearbox seen in their new CXP and PAR MK3 Series. The video in this ICS Class video show you how to quickly change the spring located in the upper part of the split gearbox.
Within 1 minute and 30 seconds if you are proficient at doing it according to Public Enemy. Not as quick as those in split gearbox type AEGs made in Taiwan and Japan (and knock-offs from China), but with all those screws, you'll need a tool to take it down and do the spring change unlike the APS UAR that doesn't require any tools.