Airsporter Age Help

[maw1]

I've been given an airsporter serial num gj13434 does anyone know the year of manufacture,have just stripped it piston was stuck in cylinder got it out but the spacer underneath the piston head has totally disentegrated,it has a metal o ring and a rubber o ring,can you get the spacer and whats the best way of tuning this up,not for silly power 11 fpe would be nice but smooth to cock fire etc,also what would be it's value good condition but a bit of surface rust etc,any help much appreciated,thanks Mark.

[webman]

Using my "Hiller Air Rifles" book, it looks like a Mk5 0.22 cal. 1971-1974.

[maw1]

Thanks for the reply,appreciated Mark.

[pennineway.fswo]

Hi Mark
The spacer that you say has disintegrated is a common problem with the airsporter. It is actually a buffer and you will need a replacement
It is also prudent to fit a new piston head (made of alloy) as the old nylon/plastic head ages and can seize in the cylinder. The new alloy head should come with a new 'O' ring
The .22 airsporter is a 10 ft lb rifle unless you have a really good one. So expect velocities of 540 - 600 ft/sec depending on weight of pellet
Suppliers of the new parts are:
Chambers
T Robb who can also supply a steel head to 'up' the power(this may not work)
John Knibbs
Ask the piston head supplier for the moly-grease to lubricate the parts (sparingly) before re-assembly
Heads cost about £10 and so does a new spring. If you replace the spring, do-not be tempted to fit a non standard high power one, particularly a square section spring. This usually brings the power down and makes the gun horrible to shoot and will wreck the gun. Just stick to standard spring
Good luck
john

[maw1]

Hi,i've resprung it with a standard spring mirror polished the end of the piston and the spring guide,greased with moly,i made a buffer plate out of some dense rubber cut and sanded flat,the airsporter shoots lovely,quick locktime and nice and smooth,shame i hav'nt got a chrono it would be nice to see whats it's running at,thanks for all the replies,Mark.