Accuracy changed in one day

**NOKNOT** · 09-26-2014, 09:01 AM

I have a Trr-Sr 22lr. The other day I had it sited in to the point I was putting shots within a dime from 75 yards. The very next day I set up, using a rest and the same ammo, and I shot a box and could not get any grouping what so ever. Any ideas what might have happened?

**JASmith** · 09-26-2014, 09:15 AM

I had a similar challenge with a .270 Winchester a few years ago. My groups with the scope were over six inches at 100 yards and the group centers varied by more than that from session to session. The see-through base let me use the factory open sights. I got something under 1.5" with a three-shot group with them, so I knew something was wrong.

I checked the tightness of the scope mounting screws -- they were tight.

I checked the tightness of the screws holding a the base to the action -- they were tight.

The remaining possible cause was a defective scope. Swapped scopes and the groups tightened to better than the iron sights and the zero stayed.the same between range sessions, so I became a happy camper.

**big honkin jeep** · 09-26-2014, 10:58 PM

Did you clean it? If so it may take a while to settle in again. Did you remove the stock? Action screws may not be torqued the same as before.

**GaCop** · 09-27-2014, 07:08 AM

What scope are you using? It could very well be the scope has gone south on ya. Check the action screws to see if anything loosened up and, as stated, check for loose scope mount rings.

**NOKNOT** · 09-27-2014, 09:35 AM

Thanks to all for the suggestions. I have a Mueller scope. I really dont have another one to try in its place but I dont think its the scope, could be wrong. I would lean towards the scope if the groups were a little bit tighter and off but they are just random, but I dont know that much about it. It has been awhile since I cleaned it, I think I read in the forum where some people didnt clean their 22s that often. I have checked the action screws loosened and re-tightened them down to about 15 inch lbs. I will clean the bore and try to see if that helps sometime today and post the results. Thanks again.

Fenrir · 09-27-2014, 01:11 PM

In my opinion, consistently hitting a dime at 75 yards with a 22 rimfire rifle is exceptionally good shooting. It would be helpful to know a bit more about your situation to determine why you experienced one good shooting session and the next shooting session did not go nearly as well. Are there any clear trends that can be seen in your shooting sessions over an extended period of time? Are you able to hit a dime every time on a day to day basis or did this happen just on one day? If you consistently hit a dime at 75 yards several shooting sessions in a row, and then suddenly one day you can’t hit the dime at all, it’s safe to say that your shooting skills are highly developed, but you probably experienced a technical issue with your equipment on that one bad day. Or did you experience one good day where you hit the dime every time but most days you are unable to consistently hit the dime at 75 yards? If the latter is the case, then join the gang, you are doing about as well as us regular guys. I will venture to guess that you experienced one rare day where the wind remained calm or very light and steady allowing you to shoot up to the full potential of your skills and your equipment. Do you have a good idea of what the wind conditions were like between the good day and the bad day? One last question, do you use wind flags?

It has been my experience that the wind can have a significant influence on accuracy, especially when shooting 22 rimfires. The best shooter in the world, using the most accurate 22 rimfire rifle ever made, will have a hard time shooting consistently well from day to day without the use of wind flags. If you were to attend a 22 rimfire benchrest match, you would see the competitors using many wind flags, even for shooting at 25 and 50 yards. They use them because they know from experience that they could not shoot consistently well without them.

There are other factors to consider, besides technical issues with guns and ammunition, that make a big difference in how well we can shoot. These factors are often overlooked because they are not popular topics of discussion on the internet shooting forums. In terms of shooting 22 rimfire rifles consistently well, the two factors that I see overlooked most often are the skill level of the shooter and the effects of atmospheric conditions. Just something to consider when comparing the results on the target from one day to the next.

**J.Baker** · 09-27-2014, 04:59 PM

I would really recommend taking a serious look at the scope as your case sounds like a classic "scope went south" scenario. You say your groups are erratic which would be a good indication the erector spring (the spring that presses the erector tube firmly against the elevation and windage turret contact points inside the scope body) broke or came loose and is allowing your erector tube to dance around inside the main tube with the recoil of each shot.

This photo illustrates the erector spring assembly in a Swarovski rifle scope, but the principle is the same in most every scope on the market as they all use a spring of some type to support the erector tube. The erector spring is highlighted in red.