POI help

[vandler]

I went to sight in my rifle and it was hitting 1 inch high and 1 inch to the right. I zero it in at 30 yrds and took off gopher hunting. missed 6 times. after the hunt i went to zero in again and i was and inch low and an inch to the left.  i don't get whats happening. When i zeroed before the hunt i ran about 30 pellets thru it and it was good. is this a lose in fps? should i inspect my seal? will temperature make this much difference from mid day to afternoon temps. new gamo with maccari tune and grt4 trigger leapers 3-9 ao scope.

[Supaflee]

Thats a big variation on POI. I`d say you have either ,1) bumped the sight or
                                                                         2) got a loose sight
 I wont say the sight is kaput yet , but it may also be the reticule floating around. Air guns are savage on Tele-sights. Is it specifically for use on an air rifle ?

[vandler]

yep. designed for air rifles. I also would like to add that my gun started  dieseling also, it got really laud/ there was a CRACK everytime i shot it.

[Supaflee]

MMMm, Bit weird , dieselling may cause a little flatter trajectory , if the velocity increases slightly , but then this is not always the case. The unknown problem is though , precisely what the effect is on every shot . What have you got in there to fuel it ??
 Can I suggest that you shoot the heck out of it until it stops combusting , then try for a group again at the same distance as before. Nothing consistant is going to be gained until it stops.
 good luck.

[vandler]

ill tighten my scope mount and run a bunch of lead thru it. see if it calms down. could a temp drop from 60- 48 cause this issue? I did a maccari tune on it 2000 rounds ago. the only lube was molly and a little clear stuff. it was great till now.

[Supaflee]

One other thing that "may ' be happening ,,,, are you allowing the fore-end to come against something solid, eg are you shooting through a doorway using the doorframe as a steady against the forend. This will make your shots go all over the place. Ensure that each time you let a shot go , that nothing other than your hands are supporting the rifle . Dont grip the fore-end too tightly , that will also make shots go left and low. .... Is it still dieselling ??

[vandler]

I have the artillery hold down and everything was great until suddenly POI wandering. I'm tearing my rifle down now.

[Danco]

So what happened seals go south? rebuild? just curious

[amb5500c]

The change in temperature can absolutely affect the POI. It's better if the gun has time to acclimate to the temperature before you try to zero.
Richard

[vandler]

so I tore it down, cleaned everything and relubed as needed. shooting like a champ... go figure. no screws were loose and seal looked ok. fresh lube helped I guess. Im going to clean the barrel and check again when the rain stops. I plan to try crowning my muzzle also.