hw100 over power

[stealth]

put my hw100 through my chrono as it was a bit erratic and using a bit more air than usual. its running at 12.7 having it turned down back to 11.5. its .177. can anyone tell me why they creep up?? using the same pellets as usual jsb 10.34
michael

[Neil54]

Could be something bedding in for example, the hammer getting smoother in its liner.
Hammer spring ends becoming polished with use.
Bit of everything.

[stealth]

had this gun serviced late last year and set to 11.5, not sure why a gun does this!! been spot on till a couple of days ago.

[TonyL]

Might this also have something to do with the ambient air temperature being higher now than when it was first set up? I know this might apply more to non-regged rifles, but just a thought, especially if it was much cooler when first done. Those air molecules will now be busier little things?

Bedding-in of components, as Neil says.

Different pellets, as in different batch, slightly tighter or looser fit?

[stealth]

thanks for reply's guys. using the same tin of pellets jsb10.34, anti tamper was taken out so i had a go and turned it back down to 11.5. it was acting like a shotgun that was what told me something not good and air going down a bit to quick. hopefully sorted now.

[simesgee]

Let us know how the gun performs, as I am a bit skeptical an extra foot pound or so would affect accuracy or consistency. Methinks something is going on somewhere in the bowels

[stealth]

spoke to the guy who did the service and he said what neil said, bedding in etc. have turned it down to 11.5 and its fine now.thanks for your interest guys.

[TonyL]

Excellent; great to hear all sorted.

[rapidresponse1]

glad you got it sorted bud