S410 FAC down to 18ft lbs

[woody2906]

Hi I have a ten year old S410 classic .22 FAC which used to achieve 25 ftlbs. It is used infrequently having only shot about 500 pellets.
Doing some zero checking and paper punching it was way off the usual chairgun aim points, usually they are pretty good. So put it over the chrono and find that it is doing a consistant 720 fps with AA Field giving about 18 ftlbs.

One advantage is the shot count is greatly increased and as I limit my pest control shots to a max of 40 yds I'm happy to leave it at that level for the time being.

But I would be interested to get the forum members opinions as to what might have caused the drop in power. It has always needed a good tug on the bolt to cock but I put that down to the stronger hammer spring needed for FAC.

[Blackbaronfish]

I would give the hammer rail a good clean and polish. It sounds like the hammer isn't hitting as hard as it should.

BBF

[woody2906]

I have never taken it apart so when it has finished this charge up I will strip it down. I don't think it will have anti tamper bolts, from reading posts on AAOC I believe cleaning and polishing the hammer rail is a must.

On another level the 18 ft/lb setting is a good compromise for a Classic giving improved shot count. Possibly the ideal would be 20 ft/lbs giving 30+ good shots.

[mark holding]

I have never taken it apart so when it has finished this charge up I will strip it down. I don't think it will have anti tamper bolts, from reading posts on AAOC I believe cleaning and polishing the hammer rail is a must.

On another level the 18 ft/lb setting is a good compromise for a Classic giving improved shot count. Possibly the ideal would be 20 ft/lbs giving 30+ good shots.

At 18ft/lbs of energy it should still retain around 13ft/lbs of energy at your preferred range of 40 yards, so plenty enough power at 18ft/lbs, plus more shot count.

[woody2906]

Finally got round to polishing the hammer rail and cleaning out all the gunk in the hammer, why do they put that in in the first place! Runs much better and easier to cock.
However there is now a leak from the base of the pressure gauge, I emptied the cylinder before stripping the hammer rail for safety sake although I know I didn't need to.
Question is this an easy fix without changing all the seals?

[Blackbaronfish]

Nip the bolt up that retains the dog leg.

BBF

[Mark112]

Nip the bolt up that retains the dog leg.

BBF

If it still leaks after doing this empty the air and replace the two 'o' rings on the gauge dog-leg. This is a simple 5 minute fix with no anti-tamper.

[woody2906]

Thanks gents for your quick responses. Seems a simple fix