APS2 vs. VSR10

[Crono0001]

So I'm getting a gun in the near future with APS2 cylinder (a broken M99 for cheap), and was thinking of upgrading it since I'm fixing it anyways.

Being an AEG guy, I have no knowledge whatsoever about spring rifles.  Are APS-2 and VSR-10 parts compatible?
Or better yet, if you want to help me out (due to my laziness), I'm looking for a spring that will get me 500+ FPS, and might as well upgrade the piston and spring guide while I'm at it.

... and that's about all I know to spring rifles.  Will I need to upgrade anything else?  I heard trigger mechanisms usually need to be upgraded as well from their stock pot metal.


EDIT:

Would I be looking at stuff like this for my M99?
http://www.airsoftextreme.com/store/ind ... ts_id=1323
http://www.airsoftextreme.com/store/ind ... ts_id=1312
http://www.airsoftextreme.com/store/ind ... ts_id=1399

Would there be anything else recommended with these items?  Anything else prone to breaking with such a strong spring?

[Rogue Fox]

If Im not mistaken the only thing that is compatible between the two are the springs. I would go with an SPM150 spring, anything higher than that will start ripping through your sears and triggers, even zero triggers dont last very long with a higher spring, not to metion slow your rate of fire.

Check out this guide, hes explains the dos and donts of sniper upgrades

http://www.airsoftforum.com/board/Tcf-s ... l96+review

[VICTORIOUS]

The APS2 DOES NOT take VSR-10 upgrades. The vsr style springs have a wider diameter, so you will need to bore out your cylinder to fit it right and use a different spring guide. The Echo 1 ASR upgrade kit will fit in your APS2 (ASR has APS2 cloned piston assembly) and is worth the price for the spring and guide, but you get a piston too. It should boost your FPS up near where you want. I don't know what a "thick type" spring is, but the parts you are looking at should fit. I have that pison and it is awesome! Trigger upgrades for the APS2 are hard to find, so good luck.

[Farslayer]

I had an APS2-SV back in 2002 with a zero trigger.  go with that.