Would that be the same way the Theoben HW80 one worked ?
In the article above they say its patented I'm guessing that would be due to the Theoben one being lapsed .
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Vortek Products Inc, long known for innovation in retrofit air gun products, has been in the air gun business since 1989 providing innovated, custom-built air gun muzzle brakes and tune kits. With many years of experience in manufacturing, we were the first to receive a patent for a “Hollow Head, nylon Tip Pellet”, and receive the first and only patent for a “center Latching” gas spring piston for air guns in 1994! We’re excited about the new and ever growing opportunities in the industry. We plan on this site to exhibit innovative design ideas as they are created that are happening right now here at Vortek.