.22 s410 carbine low on power

[joewilliams97]

I've got an old s410 carbine that's not seen too much use until I got it, the seals where shot so I've changed them and rebuilt the gun. after doing a bit of tinkering and after the advice on a Facebook forum I set out to work. I've pre tensioned the hammer spring by 1.44mm and cleaned the hammer rail, unscrewed the pot to 58mm cleaned exhaust valve off too. after putting it all back together I shot it and it didn't seem any different what so ever but was told it could possibly send the power over the 12ft lbs so I bought a chrono to test and it turns out I'm only getting 557fps which works out to be 9.85 ft lbs. currently the "venturi" power adjusting screw is out of the way giving full flow. I'd like to be up more at 11.5 please could someone point me in the right direction as to how to solve this. I've attached any information below that might be of help

air arms s410 .22
accupell 14.3
hawke airmaxx 6x24x50
150 bar fill

[Roger5]

What chrono are you using, and did you put the right pellet weight in, also try it with heavier pellet i.e. AADF 16gn or JSB equivalent

[Blackbaronfish]

Try the pot at 57mm

BBF

[joewilliams97]

just using a chrono of Ebay, just tells speed then I've been working out the ft lbs. dont have heavier pellets to hand but I have lighter ones and they're only 30fps faster so still less ft lbs

I was under the impression of the further out the pot the higher the ft lbs to a certain extent?

[Roger5]

just using a chrono of Ebay, just tells speed then I've been working out the ft lbs. dont have heavier pellets to hand but I have lighter ones and they're only 30fps faster so still less ft lbs

I was under the impression of the further out the pot the higher the ft lbs to a certain extent?

As Ray says 57 mm is the normal starting point, and a 16g pellet could up your ftlb

[Jammy13]

Hi Joe,
my 1st thoughts are use JSB 15.89gr pellets as Roger said.

Have you fitted the transfer port 'O' ring properly.

Does it need a barrel seal probe 'O' ring. Change it anyway.

Clean the barrel and make sure it's fully entered into the action and the barrel transfer port lines up with the action port.

Replace the hammer spring.

Firing valve is normally set at 57mm tho it can be anywhere near that.

If you have altered in any way the firing valve spring I suggest you replace it together with the firing valve.

With the power adjustment screw wide open I expect you will get 14+ft/lbs.

My Air Arms doesn't like accupells. Power output is about 1ft/lbs down using them.

As a guide a FPS of 566 will give you about 11.34ft/lbs with the above JSB's.

Keith

[joewilliams97]

cheers Keith I'll give the barrel a clean now. I know the barrel seal O ring is good because I mucked up the first one and had to get a replacement. mine really likes accupel for accuracy so ideally I'd like to stay with them although I'll order a sample pack of the JSB's the firing valve could be the problem and it's probably due a new set of springs now anyway. I believe it's a 2004 model

[joewilliams97]

after looking at an exploded drawing on the spares website I can only find the s410f superlight so not the same as mine but as good as, mine does not have the pot spring guide at all? I'm assuming its previously been tampered with and has gone missing. I'll be ordering one of them with all replacement springs and possibly some other parts depends how much it all comes too yet ‍♂️

[Roger5]

after looking at an exploded drawing on the spares website I can only find the s410f superlight so not the same as mine but as good as, mine does not have the pot spring guide at all? I'm assuming its previously been tampered with and has gone missing. I'll be ordering one of them with all replacement springs and possibly some other parts depends how much it all comes too yet ‍♂️

If it's a 2004 one, don't bother with the pot spring guide, it won't fit in the pot.

[joewilliams97]

If it's a 2004 one, don't bother with the pot spring guide, it won't fit in the pot.
[/quote]

perfect cheers Roger probably just the springs to replace then, could that really be all that's making it so low on power? that and 1mm on the pot?