BSA Airsporter / Mercury Adjustable Stainless Steel piston head
Airsporter Mercury / Airsporter piston head in Stainless Steel adds more weight to piston. Fits later BSAs with O ring head. Comes with three new O rings of different sizes so you can select the correct one for your actual gun, Also includes a modification you can do, to increase the stroke of the piston with this head. More air Gives more cushioning and power. (We also advise the use of our Heavy Duty Breech Seal for the Mercury) with this mod, to give a stronger seal for the extra power. It is under the options when you order. Now comes with three different buffer washers of various thicknesses, (colour may vary and may have a slight cut out for more cushion effect) so it makes it adjustable in four different positions. It also comes with a thicker pin. You can re drill offset to keep a firmer fit. See instructions included. Maximum stroke is achieved without any buffer washers. Always check the power to make sure the gun does not exceed your limit, after changing any parts.
This is not for the very early Mk 1 or 2 Airsporter that had a conical leather washer.
If you want a small bottle of MS 40 Silicon oil the please select it in the options tab below. There is also a breech seal and MS 2 Piston spring lube under the options tab.