Impact owners...

So I had her shooting lights out for a couple weeks. The other day I started missing stuff again. She was shooting a couple clicks low at 50. So I adjusted the zero n one hole again for about 20 shots. Shot well a few days. Then missing again. Back to paper. Bout 2 clicks right. Adjusted. One hole at 50 again for about 10 shots then low an inch with several in that hole then back to bull. A few in bullseye hole then a few in the other hole. Bounced back n forth between holes then another hole started. Before u know if I’ve got about 20 pellets through 3 different holes. No wind. Tried a different tin of pellets. Same. I tell you what. Extreme highs and extreme lows with this particular gun. For those of you who have followed my issues thus far...do I need to send this back to UA or FX USA? Once I got the pellet probe sorted for a few wks it was shooting one ragged hole about the diameter of two pellets with as many shots as I felt like shooting at 50yds with the occasional flier maybe 3/4” off out of every 2 magazines or so. I feel like if I go to bed after a day of killing it out there that I need to still check zero the next morning before i shoot. Every time. Is this typical?
 
With my Crown I will verify zero at the start of each session. Maybe I will have an Impact this summer.

Ok. So why? I understand if the temp is drastically different or if you traveled a ways with it and are worried about having bumped it. But if I have it shooting well one evening and wake up before daylight to go sit in a stand and hunt I certainly don’t care to be checking zero on the stand n scaring stuff off. Seems practical if you go to a farm to do some pesting, but not in every situation. Maybe a shot to make sure it’s on knowing that it likely is but just for verification. Not if you have a 40% chance of it still being on. And if it’s not on...why? 
 
Definitely not normal, but fixable, you need to find the problem, one of them can be the orings that holds the barrel (but it might not).

When I have something that I can not explain, i took my gun apart and check everything, usually works for me.

So you have an impact and have experienced poi shifts but not all too frequently? My “harmonic” rings are in place. I haven’t removed the sleeve in a couple of weeks (since I got it shooting well) so I wouldn’t expect this to be the issue. I did remove the can so that it would fit into the case and traveled with it. Put the can on and it was a little low. So two clicks up and it was on but less consistent. Traveled back home. It was off again. One click low. So up a click and on. Then off again. Then all over the place. Chrony readings still the same. Avg velocity same, es, sd all superb. So it’s not the regulator. 



If there’s anyone out who is very familiar with this gun who wouldn’t mind chatting with me over the phone about it, pm me. I don’t mind a poi shift occasionally, especially if an oring wears out or a general maintenance issue arises. But inconsistent groupings hourly/daily/weekly seems wrong. It just can’t have more down time then working time. I really thought I had it sorted for a while. Surely there’s something simple I need to watch for that I don’t know to check for.
 
@DrOcean, POI shift is definitely not normal from my experience. I have an FX Impact X 700mm (gen 3) in 25 cal with more than 7500 34gr JSB MK2 pellets thru it. The only time the POI shifted on me was when I removed, cleaned and reinstalled the barrel. In 7500 rounds, I have cleaned the barrel only once, after it had 5000 shots thru it. 

Did you check the breech o-ring? If it was leaking air, the pellet speed will be erratic and that will cause a POI change as the breech o-ring seats differently with every shot. A few more things to check:

1) make sure barrel retention screw is tight

2) make sure pellet probe set screw is tight

3) make sure barrel shroud and moderator is on tight

4) try single loading without magazine






 
Crown owner here. I run a variety of instruments and software to predict poi. Name of my game is cold bore hits and I tend to get them. I will see tiny (we are talking .2 mils or less) poi shifts changing between my moderators. When stuff gets far off, cleaning is the first thing to check. 



Other things are consistent hold. How you grip the rifle matters, probably even moreso on the impact than the Crown. 



the easiest diagnostic is to do a split whether this is a problem with the rifle, or what we in the industry call an operator headspacing issue (you). Get a friend who can shoot his own rifle absolutely lights out, and put him behind this rifle and see if he will put rounds into the same three holes you do. This way you can tell whether it's a problem with you or a problem with the gun.



I realize it is rude to suggest you may be the source of the problem, but I genuinely mean no offense. Usually with precision rifles the weakest link, the least consistent part, is the meat popsicle behind the scope. :/ Given that the rifle "seems" to be going back and forth between shooting and not, the first thing to check in my eyes is the shooter. God knows shooting is a head game and I have psyched myself out until I couldn't shoot worth a damn. So I hope this is a helpful step to take. :) 

Beyond this when doing Diagnostics I always try to break down systems into large categories and eliminate them one by one to try and narrow down the source of the issue. 
 
@DrOcean, POI shift is definitely not normal from my experience. I have an FX Impact X 700mm (gen 3) in 25 cal with more than 7500 34gr JSB MK2 pellets thru it. The only time the POI shifted on me was when I removed, cleaned and reinstalled the barrel. In 7500 rounds, I have cleaned the barrel only once, after it had 5000 shots thru it. 

Did you check the breech o-ring? If it was leaking air, the pellet speed will be erratic and that will cause a POI change as the breech o-ring seats differently with every shot. A few more things to check:

1) make sure barrel retention screw is tight

2) make sure pellet probe set screw is tight

3) make sure barrel shroud and moderator is on tight

4) try single loading without magazine






Good advice. I will re-check these things. I have not even attempted single loading as I don’t have a single shot tray and my fingers are fat. I may attempt this tomorrow though. Thanks.
 
Crown owner here. I run a variety of instruments and software to predict poi. Name of my game is cold bore hits and I tend to get them. I will see tiny (we are talking .2 mils or less) poi shifts changing between my moderators. When stuff gets far off, cleaning is the first thing to check. 



Other things are consistent hold. How you grip the rifle matters, probably even moreso on the impact than the Crown. 



the easiest diagnostic is to do a split whether this is a problem with the rifle, or what we in the industry call an operator headspacing issue (you). Get a friend who can shoot his own rifle absolutely lights out, and put him behind this rifle and see if he will put rounds into the same three holes you do. This way you can tell whether it's a problem with you or a problem with the gun.



I realize it is rude to suggest you may be the source of the problem, but I genuinely mean no offense. Usually with precision rifles the weakest link, the least consistent part, is the meat popsicle behind the scope. :/ Given that the rifle "seems" to be going back and forth between shooting and not, the first thing to check in my eyes is the shooter. God knows shooting is a head game and I have psyched myself out until I couldn't shoot worth a damn. So I hope this is a helpful step to take. :) 

Beyond this when doing Diagnostics I always try to break down systems into large categories and eliminate them one by one to try and narrow down the source of the issue.

Ha. I’m hard to offend, so none taken. Hold definitely matters. Holding drastically differently seems to throw it off 1/8-1/4” or so. No big deal there. That’ll still leave me with one (albeit large) ragged hole. It’s more than that. It also sounds louder again. Not sure why. Guess I’ll fiddle with it some more. If I can’t sort it out before the dreamlite arrives, I’ll send her off to have someone more knowledgeable look her over. This way I’ll have something to shoot while it gets looked at. 
 
Every time I miss lol . Just kidding

It really verys gun to gun and what pellets I shoot . 

But when it starts doing strange things that usually the problem most of the time . for sure the 1st thing I try .

My impact is just a smooth twist . not a x barrel. But my other guns act the same way when needing a clean. 






Ha. Yea. I’ve only put maybe 300 thru it since the last cleaning. So I can’t imagine it would need it. But if nothing else pops up I’ll try this too.
 
Meat popsicle???? Love that one. 

Guys don’t you think this is to some degree the nature of the shooting game?

So many variables Some you have no control over.

Good luck but you may never eliminate or even find the cause.

Trying another popsicle the best suggestion 

300 pellets might be to many?? I’ve seen this with every gun I’ve owned. 

We’re all chasing that perfect shooter. Maybe the problem is our expectations are unrealistic??? 
 
Meat Popsicle - let me guess, Bruce Willis, 5th Element????? Do I get a prize?

I had some problems with pellet speed variations until I completely rebuilt the gun this winter. Haven't had serious time on the chrony yet, but initial testing seems to show it's much tighter now. I'll have more info, I hope, this weekend, now that I have air again.

In my case I blew the regulatory (personal stupidity) an rebuilt the regulator, but that didn't solve the problem. It still had problems. After quite a bit of research I found the Valve Seat was crushed and needed to be replaced. I did the valve seat and all the related o-rings and now it seems problem solved. We'll see this weekend.

I understand on the earlier Impacts (mine is 2 years old now) that the valve seats were an issue you needed to watch. Once the valve seat goes, any consistency goes with the valve seat.

Since I bought the gun used, and have no idea how it was used before me, that valve seat may have been the root of the problems from day 1 for me.

To check the valve seat, first watch the Master Class videos, then look where you insert the magazine. There's a chrome circle on the front of the magazine well. There's a little chrome circle inside the big chrome circle. If the little circle sticks out, the valve seat is bad. Too easy a check not to do.

Good luck
 
I don’t personally feel that 1/2” groups at 50 are unrealistic expectations for a 2k gun...ESPECIALLY since I’ve had it shooting 1/4” groups at 50 for a week and then for 2+wks after I sorted out the pellet probe issue. It’s more than capable. It just won’t stay on for some damn reason. Haven’t tinkered with it much today except for one magazine thru it first thing. It was enough to know it was 1” off high n left from where I left it last night. Put it back on the shelf n started working on my house. May get time to go through my check list one night or this weekend. I checked pellet probe n barrel retention grubs. That wasn’t it. Valve seat good. Next I’ll do a cleaning and see. If not then I’ll look for broken orings.