BSA Scorpion

[daveh]

Hi All, My pistol is producing 400fps, I have seen Members on here claiming, 600fps. What mods will increase the output of my pistol to the same level? Regards Daveh

[Benelli B76]

If it is a .22 400 fps with a 16 grn pellet is the norm with these pistols. 600 fps will make you eligible for a jail term.

Baz

[Geezer]

What Baz said.

5.5ft/lbs (ish) equates to about 400 fps with mid-weight .22" pellets, and about 600 fps with light (7grn) .177"s.

600 fps with a typical .22" pellet would be around 11 ft/lbs - and while the Scorp might in early production models have sometimes nudged a bit over 6, there is no way in the world it could double its power through "mods", even if that were legal (which it isn't in the UK).

[daveh]

Sorry should have said its a .177 using light pellets. I hope that clarifies the situation. Regards Daveh

[Benelli B76]

Sorry should have said its a .177 using light pellets. I hope that clarifies the situation. Regards Daveh

Dave, have you tried fitting a new piston seal and main spring ? This should bring your f.p.s. up. Having said that it is harder to produce power on a .177 as you need more pressure to drive pellets down a small bore.

Baz

[daveh]

Hi Baz, piston seal looks good and spring straight and strong! What next? Regards Daveh

[Benelli B76]

Hi Baz, piston seal looks good and spring straight and strong! What next? Regards Daveh

The spring can be straight and strong but collapsed shorter in length which affects power. You need to compare length with new spring size. Also perhaps make sure it is the original spring by checking wire diameter. Is the breach seal also O.K. ? I have just got a mint boxed Scorpion which is running at 400 f.p.s. and also just repaired another one which had a jammed piston head. Repaired and fitted new seal and put the original spring back in but this one is doing 340 f.p.s. due to reduced collapsed spring length.

Baz

[daveh]

Hi Baz, breach seal is ok[ wet tissue test] spring dimensions are 3mm wire, od of coil is 21mm, free length is174mm, can you comment on this? Regards Daveh

[Benelli B76]

Hi Baz, breach seal is ok[ wet tissue test] spring dimensions are 3mm wire, od of coil is 21mm, free length is174mm, can you comment on this? Regards Daveh

Dave, from memory the diameter and wire sounds right but length could be down by 20-25 mm. There are slight variations in overall spring length. May be worth buying a spring for 20 quid if you really want more output. Think realistically you could get a max of 550 f.p.s. with a 7 grn pellet at 4.7 ft.lb. which is not to be sneezed at in an air pistol.

Baz

[daveh]

Hi Baz Thanks for your help! Regards Daveh