This is a special higher power kit above our standard model. Based off of the Tarantula kit from the late 80's. However does not use that spring.

We offer two models- choose on checkout.

HW77-97 model- Fits Mksmn 60-61 as well as old-new 77-97's

HW95-R9-10-11-HW85 etc

Includes front and rear guides. spring, piston weight, sample tar.

Piston weight drops in the piston first!

Old R10's can take one of our .790 spacers as well as the first ever generation HW77- but not required.

This kit is for perfect in tolerance guns without tube issues. Low power harsh shooting guns with issues will not deal well with this kit.

Please do not email us on if we know if your tube, model of gun etc is good. We have no idea. On guns with over sized barrels- avoid this kit.

Over sized barrels will never shoot well unless you pick over-sized pellets, get a choke put in them or whatever is required. .20's often have issues- esp. the first generation ones.

Spare springs for kit owners are available- please contact us.