Hi everyone. I have an air arms s400 .177 that's maybe 15 years old but only shot maybe 10 tins of ammo through it. It was unused for many years and now that I've taken it out to shoot again, the power is very low. It's shooting 570fps with .5g pellets which is 5ftlb back in the day it was shooting 11ftlb
Things I've tried with little change...
Various pressures from 100 to 180bar
Spacer on firing spring to increase force
Polished main guide and bushings
Replaced orings and checked for air leaks
Checked pot depth is 57mm
Checked poppet valve and even made a new one from peek
Different pellets
Verified barrel port alignment
Verified valve guide rod is clean and free
I'm reaching out cause I'm at a total loss as to what it could be. It's consistent within around 5fps. Anything else I should check?
Things I've tried with little change...
Various pressures from 100 to 180bar
Spacer on firing spring to increase force
Polished main guide and bushings
Replaced orings and checked for air leaks
Checked pot depth is 57mm
Checked poppet valve and even made a new one from peek
Different pellets
Verified barrel port alignment
Verified valve guide rod is clean and free
I'm reaching out cause I'm at a total loss as to what it could be. It's consistent within around 5fps. Anything else I should check?