I wanted to see what was the max efficiency I could get for a classic valve on a 12 gram. My set up is a standard classic AIR valve ser# CF07798, L7 bolt, (8) 3/8" ID nylon washers, Crossman 12g, RT on/off .750 pin, CCI 12b quick changer, macro line, and a piece of weed wacker string to de-volumize the macro line. Shots where 5-8seconds apart. I didn't have a chrono, but instead relied on the old "put 4 fingers in front of the barrel about 2" from the front technique. By the force felt on my finger I could tell my pumpmag was firing at or above 285 fps. Scientific? not by a long shot, but most of you reading this and comprehending what I'm saying have also used this refined technique in the past. The total shot count where 30 usable and 3 flea farts. I hope to do a vid over the chrono with Zman in the near future to get exact fps and usable shots. Also note I was unable to get the same velocity with HP air, but by subtracting washers you can reach a medium between co2 and hp. The downside sill be less of a shot count from a 12g of course. I plan on playing strickly SC so I'll stick with the 8 washers. I could probably ad 1 maybe 2 additional washers and get a few more shots, but I decided not to since I'd rather have a wider velocity range in case of cold weather.
Reply With Quote
Originally Posted by TwilightG
Where did you get those nylon washers? This is basically what RRFireblade was doing to Xvalves a while back. Rudz has one with a devolumized powertube he did.
