Airforce ???Texan .257 LSS top hat and o ring identification help please

[rodjava]

I have a Texan .257 LSS. There is a o-ring directly behind the tanks top hat. I replaced the original with the orange o-ring in the picture.
For the life of me, I can't figure out what is the purpose of this o-ring. At least it's not obvious.

Can someone smarter than me, help me out?

Rod in San Francisco

 

[RM.510bigbore]

Yes that O -ring takes all the force when the valve gets hit by the hammer and goes backwards thus hitting O-ring... My understanding

 

[rodjava]

Yes that O -ring takes all the force when the valve gets hit by the hammer and goes backwards thus hitting O-ring... My understanding

Great intel. Makes sense. At most times it's loose fitting. I never really observed when the hammer strikes and thus the top hat retracts. Thanks for chiming in.

 

[RM.510bigbore]

It took me a minute to figure it out. A Texan is a hammer hitting a valve hard then the valve opening,,,, then air and recoil behind the slug....Thus double recoil.....long dwell time for slug in 34inch barrel....Thus reason shooting Texans accurately is rough just like a flint lock...My powder burner friends can't shoot my Texan accurately at all. Know that's A different story when behind there custom powder burner s.. Airgun are a challenge but that s also what makes them fun...

 

[rodjava]

It took me a minute to figure it out. A Texan is a hammer hitting a valve hard then the valve opening,,,, then air and recoil behind the slug....Thus double recoil.....long dwell time for slug in 34inch barrel....Thus reason shooting Texans accurately is rough just like a flint lock...My powder burner friends can't shoot my Texan accurately at all. Know that's A different story when behind there custom powder burner s.. Airgun are a challenge but that s also what makes them fun...

Thanks for chiming in. Yes, you are right about the valve trigger and operation.