When trying to figure out what pressure to set the regulator to for a desired tune, does anyone else shoot the gun below the reg pressures to at least get an idea?
When I first started tuning my gun (Taipan Veteran Long) almost 5 years ago, it was such a guessing game. I knew what FPE I wanted to tune the gun to, I just didn't know where to set the regulator to get that desired tune. I've read suggestions regarding rule-of-thumbs for how much FPE a gun will get for a given barrel length and reg pressures.
I needed to be much more precise in the tune. Also, if anyone is familiar with the Taipan Veterans, it is a pain to adjust the regulators because you have to disassemble the air cylinder to get to the regulator. Setting the regulator some arbitrary amount, re-assembling the gun, airing it up, only to find that I've gone too far or not enough, only to go through the cycle again.
What I thought was, I could shoot the gun below reg pressure and carefully document both the FPS and the fill pressures after each shot. That way, since the gun is shooting below reg pressure, the fill pressure on the gun is what's in the plenum. This also means that the hammer spring tension is maxing out the velocity by the mere fact that there shouldn't be valve lock since the gun is shooting way below reg pressure (this assumes that the gun is properly tuned to begin with). Might also work great on guns with a manometer for the plenum. Avoids all the trials and errors of setting the regulator. Just have to make sure that the gun's current tune (reg pressure and hammer spring tension) is above the desired outcome tune before starting the test shots over the chronograph.
I know guns are all different with different valving, hammer weight, hammer spring etc., but at least for the Taipan Veterans, this method works great. Might also be helpful in getting other guns in the ballpark. I've tuned both the Long and the Standard Veterans multiple times with this method and I've always hit my target on the first try. Of course, have to make sure that the gun's manometer is actually accurate before doing all the test shots.
When I first started tuning my gun (Taipan Veteran Long) almost 5 years ago, it was such a guessing game. I knew what FPE I wanted to tune the gun to, I just didn't know where to set the regulator to get that desired tune. I've read suggestions regarding rule-of-thumbs for how much FPE a gun will get for a given barrel length and reg pressures.
I needed to be much more precise in the tune. Also, if anyone is familiar with the Taipan Veterans, it is a pain to adjust the regulators because you have to disassemble the air cylinder to get to the regulator. Setting the regulator some arbitrary amount, re-assembling the gun, airing it up, only to find that I've gone too far or not enough, only to go through the cycle again.
What I thought was, I could shoot the gun below reg pressure and carefully document both the FPS and the fill pressures after each shot. That way, since the gun is shooting below reg pressure, the fill pressure on the gun is what's in the plenum. This also means that the hammer spring tension is maxing out the velocity by the mere fact that there shouldn't be valve lock since the gun is shooting way below reg pressure (this assumes that the gun is properly tuned to begin with). Might also work great on guns with a manometer for the plenum. Avoids all the trials and errors of setting the regulator. Just have to make sure that the gun's current tune (reg pressure and hammer spring tension) is above the desired outcome tune before starting the test shots over the chronograph.
I know guns are all different with different valving, hammer weight, hammer spring etc., but at least for the Taipan Veterans, this method works great. Might also be helpful in getting other guns in the ballpark. I've tuned both the Long and the Standard Veterans multiple times with this method and I've always hit my target on the first try. Of course, have to make sure that the gun's manometer is actually accurate before doing all the test shots.
