POI change, RWS-460 at 45 yds. Scope is the problem right?

[Lt. Dan]

This morning I decided to shoot my RWS-460 .22 cal this morning. It was zeroed at 35 yards, weirdly it was shooting about an inch low and a 1/4" right this morning.   Hmm? Oh well, I couldn't remember if I had changed the zero or not.  I decided to move my zero to 45 yds.

I began adjusting the turrets on the scope and POI moved as it should. I had it dialed in just about perfect. POI = POA at 45 yds. I was satisfied, I was hitting the 1-1/2" spinners at 45 yds everytime.

Okay here's where it gets strange.
I take a break, fix a cup of coffee, then put some target stickers on my spinners.  Thirty minutes have passed. I sit down and settle in, take aim at the spinner, miss it completely, second shot, third shot both miss as well. What the heck?

So I shoot at a larger plate to see where it's hitting. Same size groups just low and right.
I shoot at another plate, it's hitting even lower.

Before you ask, first thing it did was check all the screws.

I'm thinking my scope is my problem. It's a Nikko STIRLING GAMEKING 3.5-10X44  AO IR. I've got three and I haven't had any problems before.

Has anyone ever had a scope drop POI  but maintain the same size group?

Those are five-shot groups after the POI change.

You can see I was popping the groundhog in the head everytime then notice where the POI dropped.

[Roadworthy]

I had a similar problem with a Nitro Venom.  After the POI dropped if I left it alone for a day or so the POI was dead on again - until it wasn't.  That was perhaps a two inch drop at twenty yards.  If I kept shooting it would come back up an inch or so after fifty shots.  I suspect piston seal but I sent it back on warranty.  Interesting.

[Deerstalker]

I had a similar problem with my HW95L and it turned out to be a loose moderator.

[SteveP-52]

I've got 2 of the Gameking's and so far haven't had any issues but I also don't have them mounted on anything that recoils are hard as
your 460 likely does.
First lame thought would be email Nikko-Sterling and ask if that model is rated for springers in case it is the scope: https://nikkostirling.com/contact

Seen any number of stories about guns going from cold to warm to cold to warm and POI changing so maybe temp is having an effect? You already
know chrony will give you a good idea if the piston seal is going bad so it would be one thing to check.

[Mark 611]

Did you change your magnification? I have had problems like this before, I usually find it's my hold or a change in air temperature wind {etc} usually when scopes go bad it's a shot gun pattern, all over the place, Hi, LOW Left, right, I see a grip change in pressure on these 2 targets IMO

[mobilemail]

Did you change your magnification? I have had problems like this before, I usually find it's my hold or a change in air temperature wind {etc} usually when scopes go bad it's a shot gun pattern, all over the place, Hi, LOW Left, right, I see a grip change in pressure on these 2 targets IMO

That is what I was thinking, or possibly a change in how/where the gun is resting on its supports. You would be surprised what a change can do, especially with a magnum springer!

[Lt. Dan]

.... chrony will give you a good idea if the piston seal is going bad so it would be one thing to check.

Chrony Beta Master at 2 ft from muzzle. Using JSB Exact Jumbo 15.89gr pellets
Results:
Shots 1-10: Avg 840, ES 48 & SD 15
Shots 11-20: Avg 828, ES 33 & SD 9

Using JSB Exact Jumbo 14.35gr pellets
Shots 1-10: Avg 841, ES 43 & SD 12

[Lt. Dan]

Did you change your magnification? I have had problems like this before, I usually find it's my hold or a change in air temperature wind {etc} usually when scopes go bad it's a shot gun pattern, all over the place, Hi, LOW Left, right, I see a grip change in pressure on these 2 targets IMO

That is what I was thinking, or possibly a change in how/where the gun is resting on its supports. You would be surprised what a change can do, especially with a magnum springer!

No change in magnification. I very rarely change magnification.  No change in the way I was holding it either. 

[gloob]

Scope in the rings/mount is another thing to check.

My gas ram Venom was a nightmare until the scope stopped creeping. I found an old scope ring in my bag with a piece of rubber glove I tried to stick in there to get it to stop moving. 

I butt the turret against the rear ring, evermore. If you don't do that, a piece of tape on the tube up against one of the rings should reveal if the scope is creeping.


Sharing the grief: I just had 3 of the best shots I ever had on a rat the other night, all within 45 seconds or so. Sitting in the fig tree, he froze in the flashlight. BAM. He jumped and fell to the ground. I reloaded, and he's still there, shifting around deciding what to do. Froze him again. BAM. Gravel spat up and he jumped in the air a foot then ran off. Two more rats ran out of the lantana, and as I scan there's a tail hanging down. Another one (same one?) froze, and I had another great shot and miss.

I get a shot this good only a few times a year, and I had 3 in a minute. Loose stock screw!

[Back_Roads]

 Sun shining on the scope and heating it up and changing the zero

[Lt. Dan]

Sun shining on the scope and heating it up and changing the zero

Nope it was in the shade the whole 30 minutes.

Scope in the rings/mount is another thing to check.

My gas ram Venom was a nightmare until the scope stopped creeping. I found an old scope ring in my bag with a piece of rubber glove I tried to stick in there to get it to stop moving. 

I butt the turret against the rear ring, evermore. If you don't do that, a piece of tape on the tube up against one of the rings should reveal if the scope is creeping.

Hmm? I looked and it seems the scope did creep back some in the mount, I hadn't noticed it until you mentioned it.

[gloob]

I don't know why I tried so hard to mount my scope "right." In addition to trying a piece of nitrile glove, I also slathered the ring screws with red loctite. Then I tried butting the front ring against the bell on my objective, for some dumb reason. It worked, eventually. After it gouged a dent in my scope.

The turret against the rear ring has never steered me wrong, so far. I just had to fabricate a couple extra long scope stops to get the eye relief right.

But this excludes a one piece on some of the shorter scopes.

[Lt. Dan]

, I usually find it's my hold ..... I see a grip change in pressure on these 2 targets IMO

That is what I was thinking, or possibly a change in how/where the gun is resting on its supports. You would be surprised what a change can do, especially with a magnum springer!

Scope in the rings/mount is another thing to check.
...... should reveal if the scope is creeping.

I apologize guys. I carried the 460 out to play again this morning. 
First I looked back in my journal, seems I was gripping the stock too tight with my trigger hand. Also should have had mythumb resting on stock behind safety instead of wrapping around.
Second, I noticed the scope had crept back some.

I made adjustments to the above items and without messing with the scope she back on target. 

Thanks to everyone for your suggestions and help.

[Struckat]

A little black book of “Holds.” Brilliant!
I only have two and can’t remember how to hold them.

[Rick67]

Even a recoilless PCP would suffer some loose ends here and there.

Was surprised when my 17xx would not group 2 days ago, so I decided to clean the barrel.

Once the shroud was removed, the loose barrel gave its guiltless smile at me.

I cleaned it anyway and was back to nirvana.

[Rick67]

A little black book of “Holds.” Brilliant!
I only have two and can’t remember how to hold them.

I have 2 who likes to be kissed 1st

[Lt. Dan]

A little black book of “Holds.” Brilliant!
I only have two and can’t remember how to hold them.

When all else fails, read the journal.  .. LOL
I have three underlevers and seventeen breakbarrels, it's hard to remember if I don't shoot them very often.

I'm not sure if it was the hold or the creeping scope. Anyway it's embarrassing. 

[SteveP-52]

Nothing to be embarrassed about, we all have off days. Even a bad day of shooting is better than not getting to at all.

[Mark 611]

Yes, tell us more!

[dtdtdtdt]

SCOPE CREEP!   SOUNDS LIKE PROJECT MANAGEMENT ISSUES?

Actually,  did you torque the screws to a "good" level with a torque wrench or cowboy wrist? Magnum springer is always a ticklish thing.

Creep suggests loose screws holding either the base or the scope tube. 

Suggest a torque wrench, it you didn't use one!

Cheers