BSA Airsporter Question

[Andy 01]

Afternoon all.

Not had one of these old girls apart before !
Was handed this one from a family member, came out of his loft after many years, and told it 'don't shoot very well' !

Ordered a service kit from Chambers, and ripped into it this afternoon.
Had a real issue getting the piston out, and had to carefully drift it out.
Piston head buffer crumbled to nothing, so I don't know what that looked like.

Fitted a new o-ring seal and supplied buffer, but trust me, that piston is not going back in !
Took the seal off, and can't even get the piston down the tube without that on.

Came to the conclusion the piston head is too big, so spun it up and started to size down.
I could then get the piston up and down the compression tube, but put an O-ring on and it just jams up solid after the first inch or so.

At this point I decided I would order a new piston head.
Chambers state the replacement head is alloy, but the one I have in the gun is a plastic like Delrin.

Is this simply an upgrade, or does this have the wrong piston head in it, which is why it had to be drifted out (and it was really tight !) and won't go back in ??

As I've not stripped one of these before I have no experience to draw on, so interested in what those in the know think

Thanks,
Andy

[Neil54]

The delrin type piston head is prone to expending.
The alloy head is better and was fitted to export models I seem to recall.

There are persons more expert than I with airsporters.

[T 20]

The delrin type piston head is prone to expending.
The alloy head is better and was fitted to export models I seem to recall.

There are persons more expert than I with airsporters.

Yes, Neil the plastic heads swelled with age.

The alloy heads seem to have been be a later fitment, both my AirsporterS have alloy heads as does my MercuryS and Mercury MK3.

I was always given to understand that the export models had steel heads.





All the best Mick

[Vic Thompson]

Not a very complete reply to you initial posting, but IMHO BSA Plastic Piston Heads swell up over time (Alloy ones don't). IMHO older Plastic Piston Heads can be re-used subject to the following : machine O D to ensure a good sliding fit without O ring, ditto O Ring Groove with O Ring fitted (machining O Ring Groove to ensure above in steps as needed).

JMHO. Vic Thompson.

[Joseyw]

Have been advised by the many good people on here that the piston seal from the Meteor is a good alternative to the Airsporter one, as it is slightly smaller and may be a easier / better fit whilst still retaining good compression.
Cheers.

[look no hands]

Have been advised by the many good people on here that the piston seal from the Meteor is a good alternative to the Airsporter one, as it is slightly smaller and may be a easier / better fit whilst still retaining good compression.
Cheers.

Correct and better using the alloy head as well.

Pete

[Phil Russell]

Airsporter / Mercury O ring = BS212
Meteor O ring = BS210

Cheers, Phil

[Cinimod]

Agree with the above comments, even though it's an Airsporter you're definitely best off putting a Meteor O ring on not the Airsporter one. It's a much better fit, being slightly smaller and causes a lot less drag to the piston. Plus it's much easier to fit the piston back in..dom

[Andy 01]

Thanks guys