I’ve been busy with my visiting family but I did mess around a bit more with the Benjamin 3030.
There’s about 1/8” of slack between the point where the cartridge is contacted by the piercing pin and the hammer. Thus the valve opens up a lot more than I think is needed.
So I made a rubber spacer…
It still pierced the CO2 cart, but not as much.
However the spacer slid and got between the hammer and the trigger (you can see the indent).
There’s a hardened steel insert in the hammer that the trigger engages. I only got a few more shots over the paltry 10 I was getting though so I pronounced it a failure, at least for now.
Then I thought about the hammer spring. Right is the “original” but probably not stock hammer spring. Center is the replacement I dug up, and left is an even weaker replacement I found in my big box of springs. I may need to make an even weaker one.
I also added an o-ring to the valve where it contacts the tube. I doubt that’s why there’s a groove there but I noticed that the valve was sliding back and forth a but as the hole in the tube that the screw sits in was larger in diameter than the head of the screw. Obviously the solution is to make a screw with a larger head…
Anyway I managed to get 20 shots with the weaker spring. Which is not a success, but lets me know that I’m on the right track. I think if I keep the valve from moving altogether I may see a slight increase as well. I think the hammer hits the valve, knocks open the seal, but then the entire valve body rebounds and bounces a but, preventing the seal from closing in a timely fashion. Or I could be wrong, which is likely. I also suspect that gas is leaking around the barrel, through the valve body and into the space between the hammer and the valve body, as well as the shot tube – sometimes the bbs bounce out of the loading port, but I don’t know if it’s the rebound or a gas leak.
The goal is the advertised “up to” 30 shots, so if I could just get it up around 25 I’d be happy. I still need to run it across the chronograph but it’s been raining for a week.