S200 mk 2 help

[Lilman2106]

Hello all new member looking for help. I got an old s200 mk 2 a couple of months back it's not the best looking rifle but it was accurate and consistent untill I tries some new pellets in it, it was still accurate but went slightly over power so reduced it so it was legal again. But then the problem started it now shoots about 5 or 6 shots consistent then I will get a big drop in fps, 760 765 609 760 226 something like that has anyone got any ideas what could be causing it please as my son uses the rifle and was doing really well with it.



Thanks I advance Paul.

[Raj]

Check for pellet clipping the silencer. If that is ok check for the integrity of the bolt probe o-ring

[Lilman2106]

Thanks raj but no silencer fitted and put new seal on it as that was my first thought.

[raygun]

Check that the small arm on the side of the action that's pulled back by the bolt is not catching/rubbing on the inside of the stock.

This can cause a large variation in power if it does rub.

ATB
Ray.

[Lilman2106]

Thanks Ray but it's doing the same in or out of the stock, I did read that on a post so also tried that.


Thanks Paul.

[eddie666]

not that well up on the pcps now a days , but could it be condensation water droplets in the main air tank,
can you ( as pcp owners ) completely empty the tank in a position were the water could drip out , then refill with a tank again , i know a pump will not fill from empty,
just a thought as we have had cold and hot weather !!

[Lilman2106]

I've emptied the cylinder and replaced the seals when I got it and as said it was shooting great until I changed pellets from light weight to medium weight. Going to try it again in the week with light weights and see how it is then.

[raygun]

Let us know how you go on.
Changing pellets may just be a coincidence and nothing to do with the problem. The problem may have just cropped up at the same time.

Going back to the original pellets will confirm one way or the other.

ATB
Ray.

[Raj]

Is the barrel clean? Could be lead crud that catches some pellets.
Is the barrel securely tightened to the action?
Is the visible o-ring - No.39 - in the brass end cap (that you can see when you unscrew the air cylinder - mates with the action) in good shape?
Is the air cylinder tight in the action? Cut some film negative and pack it in-between the brass end cap and the action block to stop it rocking.

I am trying to tackle the easy fixes first!

If none of it works, we need to start on the more involved ones.

Full strip, clean and very mild re-lube especially to following parts -
Clean well and lightly oil the valve spring - No.35
Clean and lube Main Spring - 23, Main Spring Guide - 24 and Striker - 25. Also buff up the bore that the striker travels up and down in - get rid of any crud in there.
Ensure that Roller bushes - 17, 26 and 2 x 29 are all running smooth and free and the screws holding them in place are doing their job.

If it still doesn't work, come to Rugby and I will do a full service

[Lilman2106]

Thanks for your reply raj all seals are ok as they were replaced when I brought the rifle, not knowing how long the previous pwner had had it for and what condition thy were in I changed them all. After that it was all working fine. Il have a go at the bottom part of your reply the weekend and see how I get on. But if all else fails how much would the service be ?



Thanks Paul.