Benjamin 392 delrin valve stem mod

[Longbow]

Anyone  ever try replacing the soft rubber washer with delrin ?
I destroyed 2 valve stem seals from over pumping. Also the gun could never dump 8 pumps.
As you can see in the pic , the stock seal is in bad shape with brass flakes all over it..
I read somewhere that a guy made a delrin valve stem.
I thought wow that's brilliant !

so this is what I came up with ..I cut a peace of the popet from inside the valve, for more volume in the valve and then it hit me ,maybe I can use this scrap for a new seal..
All I had to do was cut it to the same thickness as the original seal and drill a hole in it .

It was a tight fit but it went on ...You can't lightened the valve spring as much, the delrin seal needs more spring presher to seal properly but you can mod it lighter them factor..

I have been shooting the gun for over a year now even in cold weather..
I can over pump all day and never have to worry about that Achilles heel of seal 
With 10 pumps I can kill cans out to 50 yards with no holdover using 14.3g Grossman pellets
The gun will dump 11 pumps but I just do 10 pumps for long range target/ pest control.
6 pumps for 35 yards..
I did other mods , lightened the trigger...cut off the bolt safety so I can decock the gun.
It's nice being able to decock the gun while walking in the wood , especially with the lighter trigger..

So I have a ?..Do the mac1 steroid guns use the stock seal or dos he mod it with delrin ?
I here you can pump his guns up 14 time. ..

I know he strengthens other stuff like the pump arm..but I never here what gos in the valve .

[Psipumper]

I like the way you did the delrin seal. The steroid type exhaust valve is smaller in diameter and is good for durability. My chronograph showed a loss in speed with the smaller steroid style versus the crosman.