My POI is Walking!?
A little while ago, I spent a lot of time (and pellets) with the crony adjusting my rig wich is a .22 condor, 24″ barrel, removed hammer weight, with a standard talon valve.
I adjusted the top hat, my PW and fill preasure, so that using kodiaks and filling at 2650psi, i get 30 shots at 40FPE avg (thats about 930fps), with an extreme spread of less than 50fps from shot 1 to shot 30.
The thing is, last saturday i did a lot of testing shooting paper at 45 yards, and i noticed that my POI slowly “walks” from right to left for about 1.5″ total.
I can reliably repeat this all the time, first shots after a refill are little less that 1″ to the right, and then they begin to walk to the center, then past it, and last shots are a bit to the left.
I know its not the scope or the way im holding the rifle, because this happens EXACLY the same way every time i fill the rifle.
I also checked the screws on the TH, the ones on the barrel, etc. everything is snug & tight.
i also ruled out velocity change issues since the crony sais its variation is less that 50fps thru all the charge, so..
im clueless as to why is this is happening. 🙄
any ideas?
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sweet find!
Dont know benneeb0y but i had the condor apart when doing its first full cleaning and weighed the hammer and extra condor weight and was playing with the hammer and i thumped it against some solid steed and thought about the glue on on ring thing i have seen on here.
I don’t really like the idea of the glue on,figured it would come apart,and thought about this, when i hit it against the solid steel after the oring install the sound changed to a much deeper thud instead of the high whack that it had before.
Really you could probly find a softer type oring or something that had a little more give to it like softer rubbr or something and do away with even more of the sound,
Don’t know if that’s a new hammer slap mod but sounds like a great idea!
Benzin yes it is to reduce power but you can adjust it up also.for instance i have my pw at .085 with a .077 oring behind the th
, to keep 15 grain pellets down to under 1000 or adjust th down to .080 for 750fps depends on what pellet i want to shoot.
I had the top hat at .030 and the pw on 0 with good results,
but i needed more hammer preload to keep from having low fps numbers in my shot strings , so raising the pw did away with the low fps shots but resulted in to much contact, which started causing accuracy issues at around 4 of the pw, so i went to the oring.
So far with great results.
Also guys i found if you take your hammer out and pull the rubber end thing off of it ,that a oring of just the right size will slide under the rubber between the rubber and the hammer and really is amazing how much of the slap sound it take away.
Good luck ,hope this helps someone out
Knife look at your auto supply or ac supply for your o rings.[/img]
Thanks WOK, but wont it be blown away from the air leaking arround the stem during firing?
I lube the stem with silicone grease every month or so, and for the first few shots, i can see some grease being blown away from the valve face.
I have some soldier arround, ill give it a shot
i think that the POI issue is in fact caused by this, because my TH is pretty low (well it was ne way, like i said i just opened a little to test)
Put it on the face of the valve and then check the back side of the top hat.
Mike
IIRC, the oring behind the TH trick was to reduce power output wasnt it?
Thanks WOK, but wont it be blown away from the air leaking arround the stem during firing?
I lube the stem with silicone grease every month or so, and for the first few shots, i can see some grease being blown away from the valve face.
I have some soldier arround, ill give it a shot
i think that the POI issue is in fact caused by this, because my TH is pretty low (well it was ne way, like i said i just opened a little to test)
I’ve been looking for an “0”ring small enough to go gehind the top hat. Seem like I remember some playing with that some time back.
Mike
i think Voltar suggested before to put a small ring of solder behind the tophat and then just look at it after the shot to c if it got pinched
justa a thought but would a simple piece of “plasti gauge” under the tophat give a guy an idea of clearance, or if the TH is tapping the valve face?
i dunno, like placing something against the valve face and see if it gets hit or something.
Sure put a drop of silcone oil on one of the surfaces and shoot it. Look at the other surface and see if it touched
Is there any any way to test if this is happening (tophat slaming)?
i dunno, like placing something against the valve face and see if it gets hit or something.
Thanks. Mine is set pretty low, so I’ll keep an eye on it. 😉
I’ll just about Brett that if it is the case, it would be a good idea to make sure that the tank is screwed in tight and to the same point ever time.
Mike
Mike
About the POI shift when the tophat slams the valve face?
I think it was WOK or YN that mentioned.
was it you Adam?
Yes and I am sure YN has mentioned it before. It does happen and is a good thing to keep an eye out for.
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After opening the TH by about 1/4 turn to keep it from slaming into the face valve, i did some testing today.
The results? The grouping went to shit 😥
the groups i did today are about 3 times the size of the ones i did before adjusting the TH.
I also took a couple of shots at a few grackles that were on a three a litte over 80 yards away, and missed both of them 👿 😥 😳
those kind of shots are usually “routine” when firing from the bipod and with low wind, but not today.
So im returning the TH to its previous position. Ill have to find another solution to the TH slaming issue (assuming that is in fact the issue). 🙄