accuracy

o.k here is the deal i have a viper non express ....it was very accurate with the stock 3-9-40 scope on it i just put on a new bushnell 4-12-40 on and i have always used the beeman crow mag pellets but now it seems my accuracy is suffering i mean with my old stock scope i could do 3/4 inch groups all day at 40 yds with a bench but now it seems right when i think im happy with the group a few shots later ...well they seem to be wandering ....one shot its low left next its center right..so on ....so i would re adjust only to run into the same problem....i like the scope i like the magnification ....but man i tell ya im becoming frustrated ....i put the stock 3-9-40 on my big cat....it shoots awesome.....any one else run into this problem after changing optics?..everything seems to be tight....i have already put about 1000 rds through it....any ideas??

[JTK]

Hi Hunter,  could be two things imo. either your scope is bust or you are having paralax problems. If it is a AO scope try playing with the paralax adjustment. also try getting your head at the same angle and same place on the stock every time. If this fails,then it probably is the scope that is bust.  Also make sure the scope is not moving in the mount or on the rail. a fraction movement could at 40yards be a lot of poi movement.

Cheers

[Big_Bill]

Hey Robin,

Check to see if there is any play on your scope tube. the rings may be loose around the tube. A thin piece of paper between the rings and the scope tube should fix it, if that's the problem. Did you change the mounts ? and third, the scope might be bad !

Hope this helps. ..Bill

head placment is a good point i will be sure to be careful of that thank you cause i know that everything is tight...

no i did not change the mounts i used the stock mounts that the gamo scope came with and i know the scope is secure i will play around with it a little more and if i cant get it right i will replace the scope thank you....

That kinda sums up my memory of my 6-18X40 Trophy Bushnell mounted on my RWS 48.  I don't recall what the name of the one piece mount is but it is fully adjustable and has a rail pin... and was costly 10 years ago, maybe a Beeman or RWS mount.  The RWS 48 was violent enough to make the internal scope lube splatter on the inside of the objective lens.  I sent it back to Bushnell and needless to say a few shots after getting her back, she was splattered again.  It also seems to suffer from wandering groups.  It will group extremely well then start to crawl until it settles in on a different location to group again.  Very frustrating!!!

I seem to be having the same thing with this same scope on a newly tuned CFX. Dead on for a while and then it changes. I am still getting smoke so that might be some of it.
I don't think the scope is moving. I made some pencil marks on the barrel and also on the scope tube so I have a reference but I cant see any movement.

so now what....replace the scope? they claim this banner series i have is made for springers.....

I'm going to keep working with it for a while to see if it settles down. I really do like this scope.

I have had the same problem with 3 scopes mounted on a tuned CFX with a Gamo 1 peice mount. I will literally put 5-6 rounds in an area less than 1/2 inch at 20 yards and then all of the sudden 5-6 are all over the place. Latest scope is a Centerpoint Adventure Class 3-9x40 RG Illuminated. All screws are treated with loctite. I really don't think it's the scope at this point. If you ever figure this one out, PLEASE post the solution.

[gamo2hammerli]

Does the scope have AO (Adjustable Objective).  I'm new to airgunning...but have been reading about pallalex (sp.)....apparently most rifle scopes are set for longer shots...  With airguns....we usually shoot around 30 to 40 yards or meters...so there might be pallalex and it will affect point of impact.

Mine scope is AO. I think I basically narrowed my accuracy problems to inconsistent pellets and/or my CFX is really rough on scopes. I mostly use JSB Exacts and JSB Match. Some get roughed up in shipping. I ordered a few more different kinds but I have to wait to get my gun back from CDT.

I was having the same problem with my tuned CFX and Centerpoint 3-9x50 scope.  It has only had roughly 200 rounds through it since the tune but I would expect my groups to be tighter.  If you are new to airgunning, like I am, try working on the fundamentals of shooting.  My groups have been getting tighter with more and more practice.