I know nothing about this kit, but have had an HW 45 for many years (actually a Beeman P1 from the first year they were made) and love it. You might find this thread by expert tuner "Stevoo" of interest. Note in particular his comments on optimum piston weight, which was adversely affected by whatever kit he was referring to back in 2020.
Another key to HW 45 happiness (discussed by Stevoo in another thread which I can't find!), is simply to use light pellets. Faster shot cycle = less recoil effect = more pleasant shooting and better accuracy. Mine loves JSB 7.3 Exacts.
I wanted to share what I believe to be the best way to tune the HW45 pistol after approx 30 years of owning and tuning. First, you can just leave it stock and shoot it. If you resist adding any additional lubrication, it will eventually expel, or burn off the excess lube put into it by the...
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