Muzzle Energy Dropping Off

[Tommy_uppy 2]

Hi

I'm having an issue with my BSA Ultra multi .22 it was running fine last year, then I noticed that the muzzle energy had dropped to 10.5 fps. I thought this was a problem with the foot pump I was using and recently brought a dive cylinder. The gun went off for a service and they didn't find anything wrong with it, but it had new seals and a clean. I tested it again today because the pellets were dropping off the target, it had dropped again to 7.5 FPS. I've stripped it down and cleaned every part but that's not made a difference. I've been itching to go out hunting but I don't trust my gun at the moment. Does any body have any ideas?

[robwelsh 354]

10.5 ft lbs, was fine. Lol

You won't get any ideas on open forum about power.

I'll pm u now.

[Tommy_uppy 2]

I think I was misunderstood. I'm not trying to break any laws. There is a problem with the power dropping off at the moment it wont go above 7.5 Foot pounds. Is there anything I can do to fix this myself or does it have to go back to the shop again.

[Tron 173]

Its possible the hammer has been lubriated with a thicker oil than usual, those models need a very small amout of lubricant something like WD40 is ideal ordinary gun oil is too thick and with the very cold weather we have at the moment it thickens up gun oil, creating drag on the hammer which affects the velocity. make sure though first that the tiny O ring on the pellet probe is not damaged or even missing as that can lose you 4 FLBS easily.

[Tommy_uppy 2]

The O Ring looks ok. I don't think its the oil but I will try some WD40

[robwelsh 354]

Run the hammer an spring dry, oil will make it vary from 7.5ft lb to 10 , but the figures u sent me seem consistent

[Tommy_uppy 2]

Thanks for everyone's help. Its up to 10.35 which is more usable.

[robwelsh 354]

Did u follow what I said mate?

[Tommy_uppy 2]

Yep I tried that as well it was surprisingly easy. I've also been looking at John Bowkett. I think I might try him if it does it again.

[Tron 173]

Its possible the hammer spring has lost a little power, At the back of the spring there is a threaded cup which is for adjusting the power output. If its still under 11FPE its worth adjusting to put a bit more preload onto the hammer spring to your preferance.

Edited February 16, 2013 by Tron

[villaman 9,983]

If you have no joy ,give Darrin a call http://www.xtxair.co.uk/

[Tommy_uppy 2]

Cheers, Have you used him, can anybody tell me the difference between the two?

Tron - I have tweaked this but I intend to put some heavier pellets through next week. I will tweak it again if its still a long way under. Its just not worth going over the limit.

[robwelsh 354]

Tommy be careful still, my .20 cal shoots lighter pellets at more ft lb lol

[villaman 9,983]

Cheers, Have you used him, can anybody tell me the difference between the two?

Tron - I have tweaked this but I intend to put some heavier pellets through next week. I will tweak it again if its still a long way under. Its just not worth going over the limit.

 

Yes mate i have used Darrin xtxair , had my ultra regged by him, .a very nice bloke and a very very good job Darrin made of it