This was installed on my Hatsan Neutron Star (H-NS) air rifle in .22 caliber. Though I don't have the tools to measure sound pressure, I can definitively say it SIGNIFICANTLY reduced the loud report of the unsuppressed H-NS to the extent no earpro was necessary outdoors. Not unsurprisingly, there was no shift in point-of-impact after adding the suppressor!
I discovered upon first threading the suppressor onto the H-NS muzzle there was a 0.208" (5.31mm) unsightly gap remaining when the suppressor "bottomed out". A thick gold-colored flat washer sandwiched between two black rubber washers - all of applicable size (0.248"/6.30mm total) - complemented both the functionality and aesthetics of the setup.
This is a quality, well-constructed, user-serviceable device which serves its intended purpose masterfully! I highly recommend this suppressor and the Airgun Capital business. The folks are friendly, professional, and ready to help in whatever way necessary. Their website is an added bonus as it accurately reflects current in-stock inventory and provides an easy checkout experience.
Great job, Airgun Capital!