Ronno6 Adjustable piston in 822

[RichH]

Last year I got an 822 from Ron. Wanted to up the power so I made the piston solid. Last week Ron sent me a message asking if I wanted to try out his Adjustable piston with dual o-rings. He sent it and I did. I adjusted it to be the exactly the same as the original. I have the results in the pic. Below are the numbers from when the original piston with ES was in the gun. (I didn't have original numbers with 12 pumps)
All testing with Crosman 14.3
Original                             Solid                           Ron's Piston
3 Pumps - 376 avg            381 avg                      398 avg
5 Pumps - 457 avg            480 avg                      496 avg
8 Pumps - 538 avg            566 avg                      581 avg
10 Pumps - 567 avg          605 avg                      628 avg
15 Pumps - 617 avg          669 avg                      701 avg

So you can see while my solid stack increased the velocity at the higher pumps, Ron's adjustable also increased the velocity over the solid stack at all pump levels. The increases were between 20fps and over 80fps (at 15 pumps) compared to stock piston. I believe this really shows the benefit of the dual o-rings.
The only "negative" that I see it that you have to be certain to extend the pump the full distance on every stroke. With the original and my solid stack I can hear the air when it is drawn into the tube. With the dual orings I can't and if I pump quickly or don't ensure full extension I noticed a slightly lower velocity. This is why I did 4 shots at 15pumps. I think the one shot was low due to me not fully extending.


Side note - my 822 does have a metal pump arm

[Ronno6]

Thanks, Batman......

Nice numbers for a .22
The first O-ring is really the same distance from the piston face.
Pumping should not really be any different.......

Your 822 also benefits from the metal pump arm.