Poorly Airsporter Mk6, 0.22"

[PhatMan]

Hello to All,

Just stripped down my friends Airsporter Mk6 in 0.22"

The rifle was making ca. 5.4 ft.lb with 14.3 gr. pellets, so I would suspect is a bit poorly

The piston head buffer washer had totally dis-integrated, and the piston was a right sod to remove. The 'insides' were drier than a dry thing

I have ordered up some spares (standard spring, alloy piston head & seal/washer kit).

When re-built, what would be the 'par' energy I should be looking for - around 9 to 10 ft.lb ?

I was very surprised to see that the piston & spring guide were made from sheet metal, rolled into shape !

Definitely not what I expected from BSA & one of their 'flagship' models !

Have fun & a good Bank Holiday

Best regards

Russ

[landymick]

10.5 ft.lb is about right on these.

[Shed tuner]

make a new piston head (no buffer) to take a diana 28mm parachute seal; will make 11 FP+ easy (due to 6mm increased stroke, and better sealing efficiency). With the std arrangment, 9-10 Fp is plenty, as they get harsh.

[PhatMan]

John, Mick,

Many thanks

I think my friend will be happy with anywhere between 9 and 10.5 ft.lb

He just wants the old girl to be back on her feet, and shooting sweetly with it

Have fun & a good Bank Holiday

Best regards

Russ

[Benelli B76]

Russ, if the piston head was nylon you could have just skimmed it down (they expand through absorbing moisture) and there is a standard rubber tap washer that makes a good buffer washer. You just have to open the centre hole with a 10 mm drill. Done quite a few like this.

Regards, Baz

[Airsporterman]

Around 10.5 ft/lbs (factory spec) with a standard spring - but expect it to take a few shots for things to bed down after a rebuild!

ASM

[PhatMan]

ASM. Baz,

Many thanks

Yup - the head was a bit swollen - I will get a friend of mine to give it a skim.

If you partially cocked the rifle, the piston assembly didn't return to battery - it stayed where it was !

Have fun & a good Bank Holiday

Best regards

Russ