I was going to upgrade two of my guns (G&G M4 and G&G UMG). Both shoot about 400fps w/ 0.2g bbs (although i use 0.25's). I was going to install the following upgrades:
Modify Baton Ryusoku AEG Flat-Type SOFT Hop-Up
http://www.airsoftparts.ca/store2/in...oducts_id=2808
Prometheus HOP Tensioner
http://www.airsoftparts.ca/store2/in...oducts_id=2666
Does anyone know how these will effect the accuracy and range on my guns?