Spending some "quality lockdown time" with my old Marauder, I was reminded of the air puff in the face every time I pulled the trigger. So I decided to do something about it and the project grew into something else - a way to make a significant improvement in performance!
First, I blocked the hammer spring adjustment hole with my thumb. That stopped the puff of air but the muzzle velocity fell - which was definitely NOT what I wanted. So, I ended-up doing some full-scale shootdown testing and found some surprising results. Yes, blocking the hammer spring adjustment hole reduced muzzle velocity, but it also lead to a much flatter shot curve. Something like a "regulator lite" effect.
With a flatter shot curve, I was able to give the gun a more aggressive tune, ending-up with more power, more shots, or both. Then a ton of testing with unregulated Marauders in all three calibers proved that it works every time with no less than 12 combinations of gun and pellets. But a little different with every individual gun/pellet combination. Here's some examples...
In .177 cal, the result was double the number of consistent shots - in fact more, as you can see above. The next graph shows that much increased FPS (and power) was achieved in .22 caliber - over a 25% increase in FPS over 30 shots.
Even the .25 cal Marauder gained up to 10% in power and shot count - as well as eliminating that pesky air puff in the face. And in no case is it necessary to make any change to the gun which could invalidate the factory warranty or requires dismantling the gun - beyond removing the stock, that is.
You can see more detail and a ton of test results in Hard Air Magazine. Plus, I've put together a simple, low cost kit that enables anyone with an unregulated Marauder air rifle to achieve similar results for themselves - even without a Chronograph. It's an ideal lockdown project!
https://hardairmagazine.com/ham-columns/benjamin-marauder-tune-kit-can-add-100-fps-or-double-shot-count/
https://hardairmagazine.com/ham-columns/more-test-results-for-benjamin-marauder-and-armada-tune-kit/
https://hardairmagazine.com/ham-columns/theory-of-operation-for-the-benjamin-marauder-tune-kit/
Have fun
First, I blocked the hammer spring adjustment hole with my thumb. That stopped the puff of air but the muzzle velocity fell - which was definitely NOT what I wanted. So, I ended-up doing some full-scale shootdown testing and found some surprising results. Yes, blocking the hammer spring adjustment hole reduced muzzle velocity, but it also lead to a much flatter shot curve. Something like a "regulator lite" effect.
With a flatter shot curve, I was able to give the gun a more aggressive tune, ending-up with more power, more shots, or both. Then a ton of testing with unregulated Marauders in all three calibers proved that it works every time with no less than 12 combinations of gun and pellets. But a little different with every individual gun/pellet combination. Here's some examples...
In .177 cal, the result was double the number of consistent shots - in fact more, as you can see above. The next graph shows that much increased FPS (and power) was achieved in .22 caliber - over a 25% increase in FPS over 30 shots.
Even the .25 cal Marauder gained up to 10% in power and shot count - as well as eliminating that pesky air puff in the face. And in no case is it necessary to make any change to the gun which could invalidate the factory warranty or requires dismantling the gun - beyond removing the stock, that is.
You can see more detail and a ton of test results in Hard Air Magazine. Plus, I've put together a simple, low cost kit that enables anyone with an unregulated Marauder air rifle to achieve similar results for themselves - even without a Chronograph. It's an ideal lockdown project!
https://hardairmagazine.com/ham-columns/benjamin-marauder-tune-kit-can-add-100-fps-or-double-shot-count/
https://hardairmagazine.com/ham-columns/more-test-results-for-benjamin-marauder-and-armada-tune-kit/
https://hardairmagazine.com/ham-columns/theory-of-operation-for-the-benjamin-marauder-tune-kit/
Have fun