Power Adjustment on an S400

[Stephen1974]

Hi all, long time no post...

I am looking to have the power adjusted on my S400 and I would like to know how it is done. I've tried looking on forums and for videos but not found anything other than people talking about anti-tamper screws.

I have had it adjusted twice before, once down to just under 6ft as the indoor club i was at at the time demanded it, and then back up to just under 12 when i started shooting outside again. However, after that second adjustment the rifle seems as accurate as a US marine (couldnt hit water if they fell out of a boat). I plan to have someone else look at it and do the adjustment, but I want to understand the process.

Am I looking for a screw than need adjusting? Where would I look for it? What does it look like?

On the right side of the rifle there is a screw with a hex head and I have seen images on e-bay of 'power adjustment grubs' with an arrow pointing to the location of this screw. Is this it?

I've seen people talking about anti-tamper screws. The only screw I have that appears to be anti-tamper is on top of the rifle. The 5 screws, that surround the breach. The one at the back left has no head on it. Initially I thought maybe one of the places that adjusted it before swapped them around for ease of use but im not sure they are the same sive. The one on the side seems a lot smaller.

If it is the screw on the side, I assume its adjusted simply by turning but which way increases and which way decrease the power? can you damage the rifle by turning to much and if you can, how much is too much?

Some of the ones listed on e-bay appear to be spring loaded with a larg knob on the end so it can be easily adjusted without tools? Is that the case? Not sure Like that idea but again, just looking to understand the process.