Bsa scorpion pistol help

[nat1]

Hi, need a little help with a mk2 bsa scorpion pistol i've acquired.

The piston has siezed in the safe/fired position so need to strip it down. Is there any pre-load on the spring (don't have a spring compressor!) and is it just a case of drifting the big pin out of the back of the cylinder?

Any help appriecated ,Woody.

[bsa-nige]

loads of cheap spring compressor on a well known auction site that would sort it

[les allam]

Hi Woody
There will be some preload on the spring, I used a piece of broom handle 4" long with a slot cut out of it ,the same size has the retaining bolt. I use a sash cramp,the cut in the broom handle thingy needs to be about 1" deep.
Good luck with your pistol.
Regards
Les..

[Troubledshooter]

The 'Big Pin' at the rear of the cylinder is a shaped pin in which the spring guide sits, and is not suitable for drifting. You will definitely need some form of spring compressor

[original45]

As said no don't just drift it out you may damage guide and pin as it has recesses cut in to sit guide on .
As said a piece of rounded wood or a bit of steel tube just big enough in dia so you can cut away a recess in it for it to slip past the pin and take the pressure off the mainspring whilst you push out the pin.

Once you cut your steel it's trial and error as to if you need to cut it deeper as it takes a few mm of lift so as it comes out freely.

Never needid a compressor on mine but you will get a idea of amount of pree load when you try your bit of steel to lift guide of pin.

[Troubledshooter]

I use a piece of folded aluminium strip which fits nicely over the pin.

[nat1]

Many thank for all the help.

Have used a sash cramp now , all parts have now been cleaned and where possible polished ready for lube and the new seals/buffer.

Once again, cheers, Atb,Woody.