How to Upgrade an Airsoft AEGsource:
http://www.wikihow.com/Upgrade-an-Airsoft-AEGThere are a lot of upgrades available for airsoft AEGs. This is a basic guide to the parts you need to upgrade.
For a Bolt Action Rifle1.
Barrel. The tighter the barrel the better your accuracy and consistency will be. PDI, Laylax and Dees Custom make them. Marui also makes a precision barrel and chamber set which is quite good.
2.
Hop Up Rubber. The Hop Up Rubber gives the BB back-spin increasing the range and accuracy. GET A GOOD ONE. Nine Ball and FireFly make good ones.
3.
Piston. The piston compresses the air in the cylinder. Some have air brakes which silence the gun but this reduces the power. The lighter and stronger your piston the better.
4.
Spring. The stronger the spring, the faster the piston is forced forward, and the higher the muzzle velocity. Get a good quality one. Laylax make great ones.
5.
Hop Up Chamber. Most clone and chinese guns come with poor chambers. Getting a good one will greatly improve accuracy. The Marui precision one for the VSR-10 is excellent.
6.
Piston head. The piston head forces the air into the barrel, propelling your BB. For the VSR-10, PDI and Laylax make good ones.
7.
Spring Guide. This stops the spring from jumping about. Most guns come with plastic ones. Get a metal one and it will last longer.
8.
Cylinder. If you get a teflon or polished cylinder you will have a easier bolt pull. Teflon on your cylinder means you don't need to lube it.
9.
Bolt Handle. If you have a big bolt handle it will be easier to cock your gun. Guarder makes them for the L96 and APS2. PSS10 makes them for the VSR-10.
10.
Trigger seat. Don't be tempted to get a cheap trigger seat. If you fit a very strong spring change your trigger seat. It keeps the gun cocked. If it breaks your gun will not cock.
11.
Piston seat. Catches the piston and is supported by the trigger seat. Has a lot less strain put on it than the trigger seat.
12. Spring Guide Stopper. Keeps the cylinder in place. You should also upgrade this when increasing the muzzle velocity.
13.
Trigger mechanism. The best triggers are zero trigger. They require only a light trigger pull and are very strong. Comes with a spring guide stopper, piston seat and trigger seat.