Contact the maker to see if it is possible and what it will cost.
It is possible. It is best to have a professional do it. AirsoftGI has a great upgrade service. FPS ces from the spring in your rifle, the hard it is to compress the spring, the harder it shoots. AirsoftGI can install a harder spring for you. Airsoft Tech is confusing, and is best to leave it to those who know what they are doing. (Unless you do hours of research and practice on cheap gins/gearboxes)
No
Not AFAIK
Airsoft Megastore 7.00$ -Jeff
I don't no about spring, but the Green Gas M700 Sniper Rifle Competition Professional Airsoft gun, has 720-FPS!!!! And the, Spring CSI L96 Bolt Action Airsoft Sniper Rifle, has 550-FPS. They are both from, Hobby Tron.com
Yes
The Well MB03 Spring Airsoft Rifle measures approximately 38" long.
go for the m14, unless its cheap looking.
i think its the echo 1 asr. it costs 115$ (on airsoft gi) and shoots at 480fps out of the box but you can upgrade it to shoot at 530fps if you get a tight bore and the upgrade kit.
if it is electric, or gas, yes. if its spring, its not.
Yes you have to every time. It depends on the spring tension.
Not sure what the question is, be more specific, each gun has its own magazines, and spring guns suck if not bolt action rifles or shotguns.