Breech seal air leak

[solder]

I have read that you can check for air leaks by putting a tissure over the breech and seeing if it moves when shooting. Is some movement acceptable? Should there be no movement at all? What are your results on having tried this with various airguns?

[anti-squirrel]

There shouldn't be any movement at all.

I've used this method on all my break-barrels and they are all fine.

The other guns?  The TS-45 blows more air out the breech assembly (sidelever) than it does down the barrel.  It also has a bent/compressed piston seal screw, the piston seal itself is in dire need of replacement, and pellets fly laughably slow- half the speed of my Model 25 BB gun.  Despite this guns many misgivings, it is accurate for the speed of the pellets.  I feel like I could take a shot, walk up to my target and move the bullseye in front of the pellet's path to ensure a perfect shot.

I never bothered with the B3 underlevers.  At $45 each, I'm not gonna sweat things.

[Whirligig]

I have read that you can check for air leaks by putting a tissure over the breech and seeing if it moves when shooting. Is some movement acceptable? Should there be no movement at all? What are your results on having tried this with various airguns?

Corn starch works too.