Reply To: Benjamin Discovery Velocity
Using the graph I found online as a reference, I decided to shoot for a .095″ port size. I turned a new transfer port out of stainless steel 1/4″ rod and drilled the I.D. to 0.093″ because that is the closest size of bits I had on hand. Original transfer port size that came with the gun was .140″
Unfortunantly I did not gain as many shots as I was hoping for when looking at the graph. I only gained 6-8 shots vs using the stock port. Oh well more shots is better then zero! I decided to just get over it and just have fun with this Disco. Studying the shot string it seems I can go to a higher fill pressure ,but I don’t have a degassing tool in case I lock up the valve.
After moving the barrel band forward I improved the accuracy a little and I am able to obtain 1/2″ groups at 35 yards using el cheapo Crosman Premier 14.3 pellets.
Shot string Crosman Premier 14.3 2000 psi fill: