Can I tune my at44 to be more quiet?

Hi guys, havent been around much but i have been trying to shoot when I can.

So now I only have my hatsan at44 .22 single shot, I like this gun alot! I've tried to sell it, but I can't because its such a nice rifle. Plus now that they've gone up 100$ in price it makes me realize if I regret selling, it might be hard to replace...

My issue is, despite being very quiet compared to high powered pcp's, its still a little loud for the quiet neighbor hood I shoot in. It seems to sit around 100-101decibals 3' from the muzzle.

Can I lower its noise report through tuning at all?

Right now I have the 3 lower valve ports blocked, hammer spring preload is barely turned in ( I couldn't tell you how many turns off hand) and I have the valve stem polished down to achieve 480-490fps with 14.3gr pellets.

Thanks guys

Thinning out the valve stem and increasing the hammer strike both would have, unfortunately, made the gun louder.... Power and quiet don't normally go together.... Your gun will be quieter at higher pressures.... Try running it from 190-200 bar down to only about 150 bar before refilling it.... PCPs typically get louder as the pressure drops....

Bob

Thank you bob, I kind of figured that was the story.