Originally Posted by
Lawrie Amatruda
My method to reduce the power is to solder a thin walled piece of brass tubing inside the valve guide, to blank off the exhaust holes, this guide has two or four holes drilled round it, then all that is needed now is to drill some new holes smaller than the originals, I have found over the years working on Sheridans that the ones made for Europe with the low power limits, have holes approx 1/16”, the Uk ones are approx. 3/32” and the USA ones approx. 3/16”, this always works for me, sometimes minor adjustments to the holes are necessary, so I always drill slightly smaller than I think may be needed so that I can open them a little at a time to get the balance right, I occasionally, increase the power of the hammer spring so that the valve stays open when firiring so that all the air is expelled in one go, after doing this, you then find that it is almost always necessary to cock the gun before pumping.
Cheers, Lawrie