Last time out my WC .177 was shooting low. I have a Huma reg and gauge in it so I knew it wasn't that. Gauge is steady as can be so I just figured I bumped my scope. Just took it out today and it was low and not grouping as well. Took it into the garage and ran it over the chrony. It had been shooting 915-925fps. I start shooting and my reading are from 845 up to 880. What the heck?
I just happened to have read this post by likkitysplyt about what Ernest did for his erratic WC
FX Wildcat 25 MKII – Huma regulator is here!![/QUOTE]https://www.airgunnation.com/topic/...a-regulator-is-here/embed/#?secret=7Tkodj7Vjs
Sure enough I take it apart and here is what my A9 o-ring looks like
I never would have believed that O-ring (sealing the back side of valve stem) would make that big of a difference. The diagram calls for a 2.5x1.5 90 duro. All I had on hand was a 70 duro so I put that in for now.
I run it back over the chrony and it's shooting 935. I backed off the HS about 1/2 turn and I got it back between 915 and 925.
Just gotta order a pack of 90 duro now.
I just happened to have read this post by likkitysplyt about what Ernest did for his erratic WC
FX Wildcat 25 MKII – Huma regulator is here!![/QUOTE]https://www.airgunnation.com/topic/...a-regulator-is-here/embed/#?secret=7Tkodj7Vjs
Sure enough I take it apart and here is what my A9 o-ring looks like
I never would have believed that O-ring (sealing the back side of valve stem) would make that big of a difference. The diagram calls for a 2.5x1.5 90 duro. All I had on hand was a 70 duro so I put that in for now.
I run it back over the chrony and it's shooting 935. I backed off the HS about 1/2 turn and I got it back between 915 and 925.
Just gotta order a pack of 90 duro now.
