Hi,
I am attempting to fine tune my Benjamin Marauder 25 caliber with the famous 40 shots/40 FPE tune. I have modified the air rifle with the Tim Hill modifications by widening the transfer port, changing the valve, hammer, hammer springs, and lighter hammer striker. I've also added a huma regulator with integrated pressure gauge and set it around 130-140 bar. It's currently shooting the 25.39 grain JSB Exact pellets at an average of 846 feet per second with a standard deviation of about 6 feet per second.
Below it's one of the 40 shots string, and I am having some difficulties in "flat lining" the shots vs. having the peak in velocities seen in shots within the middle of the shot string.
Question: Is the below pattern indicative of a regulator pressure or hammer spring tension increase or decrease? Or, do both need adjustments? I believe I am close and any direction and/or guidance is much appreciated!
I am attempting to fine tune my Benjamin Marauder 25 caliber with the famous 40 shots/40 FPE tune. I have modified the air rifle with the Tim Hill modifications by widening the transfer port, changing the valve, hammer, hammer springs, and lighter hammer striker. I've also added a huma regulator with integrated pressure gauge and set it around 130-140 bar. It's currently shooting the 25.39 grain JSB Exact pellets at an average of 846 feet per second with a standard deviation of about 6 feet per second.
Below it's one of the 40 shots string, and I am having some difficulties in "flat lining" the shots vs. having the peak in velocities seen in shots within the middle of the shot string.
Question: Is the below pattern indicative of a regulator pressure or hammer spring tension increase or decrease? Or, do both need adjustments? I believe I am close and any direction and/or guidance is much appreciated!