I was just at the range shooting 3/4 MOA groups at 100 yards on a ladder test... When suddenly my last heaviest ladder group scatters everywhere at a 2 foot radius. I then checked with a proven load and it’s still scattered.

I think obvious things to look at are my scope mounts and the scope itself. I’ll check screws and bedding on my picatinny rail, and I’ll check the tightness and position of my Warne PA Rings. I’ll check my scope (Leupold VX3i 2.5-8x36) with a box tracking test. I have already checked action bolts torque when I was on site, but I will take the stock off later to see if there is any obvious with the bedding.

So is there anything else I need to consider?

Thanks,
Frank

Gee, sorry to hear this.
Let's hope it's somthing easy to fix.

I’m thinking most likely issues are scope mounting or the scope itself. It’s a bummer that I don’t have another scope to try - so that’s why I want to get into a box tracking test.
Any other recommendations?
Thanks

After you secure the mounting set up, go back to the proven load and shoot a group. If it groups it was the mounting. If it doesn't group then a tracking test is a waste of time.

If tracking test is a waste of time, can you suggest any way to check the scope itself?

Use a mirror laid flat on a table and center the reticle of your scope, then whack the scope in the palm of your hand a few times and put it back on the mirror to see if the reticle remains in alignment with the reflection in the mirror.

Two foot? Bad chit. .When you redo your mounts, note if everything was loose as hell or not?

I put my scope on a mirror as suggested and it was interesting to see reflected shadow of crosshairs thru the mirror. So I adjusted the elevation and windage knobs to align the shadow of the crosshairs with the crosshairs as I assume you suggested for me to do. Then I “whacked” it with palm of my hand as suggested and I did not see any change in alignment. Please confirm whether I got all that right.. And thank you!

I just took everything apart and I did not find any of the mount screws to be loose. I checked with a torque driver. Base of rail to action appeared to still be 20 in-pds with blue loc-tite. Epoxy bedding on rear mating surface from rail to action still seems good. Bottom screws on vertical Warne PA Rings still appeared to be 25 in-pds, they were forward in the picatinny rail slot, and top ring screws to scope still appeared to be 20 in-pds.

I am using acetone to clean the loc-tite residue from rail screws, bottom of rail, and from the action. And I am similarly cleaning all other screws and mating surfaces. I’ll put everything together and give it another go at the range next week.

I would be grateful for other good ideas. Thank you

Sounds like you got it right, Frank. The technique can't prove a scope is good, but it can prove one is bad when you see the reticle go out of alignment with its reflection.

Hope you get the problem figured out without too much fuss!

I had two rifles go from 1" or less to 2" or more last weekend. After I tightened the loose action screws they returned to normal. Just mentioning it.

Thank you all. I just put everything back together and I will give it another go at the range next week.

What is the rifle and chambering?

Could it just be a dirty barrel? Although I have never seen one go that far out that quickly, I have seen accuracy deteriorate relatively quickly once I reach the point where it needs to be cleaned.

Sigh....


A dirty barrel is not producing 2ft groups.


Op,

You have a total scope failure, mount failure, loose barrel, or extremely loose action screws.

It’s a very basic budget hunting rifle setup in 308win. Specific model is Browning AB3, with bedded pictatinny scope rail, Warne PA Rings and Leupold VX3i 2.5-8x36 scope.

I thought about the cleaning aspect, too, but still had problem after I cleaned it. Thank you for the response

AB3’s generally shoot well.

Vertical split rings are garbage and cause for quite a few scope issues. Leupold is beyond suspect.

Interesting problem and it's got me thinking (look out below! ;)).




I could be wrong, but this to me says something BROKE. Suddenly.

I know you've tested the scope like I suggested, but it did not really PROVE the scope is good.

Ever had a guard screw fail? I'd have a look at the bedding just to make sure there's not some kind of structural or mechanical problem.

I think I'd mount a different scope on the rifle for the next trip to the range, if it was mine.

I’d check:
1.Scope mounts
2. Carbon ring in the throat.
3. Excessive copper fouling
4. Scope
5. Muzzle device fouling and installation

Two feet is mega haywire. Are the bullets keyholing?

Could your powder charges be varying wildly?

Thank you. I took the scope mount completely apart, cleaned everything up with acetone, and torqued everything per manufacturer recommendations.. And I did same with the action and its screws. Being a Browning, I’m pretty sure the barrel will never come loose from those fine threads and red loctite. I hope I don’t have a scope failure.

I was at one point getting a lot of really nice 3/4-inch groups with everything I had - but it seemed like something came loose with my last few test shots.

Sadly this is where your heading! Been there done that.


https://www.leupold.com/service-support/services-repair

I’ll reiterate this.

Getting everything right with vertically split rings is substantially more difficult than with other designs.

I doesn’t take much misalignment and/or excess clamping force and/or out of round rings to stress an optic. The consequences are magnified when dealing with a lightly built optic.

When you inspected the scope on the mirror, was it still mounted on the rifle?

Did you use a quality set of scope alignment bars to see if the rings when mounted to the base are lined up (both parallel and in the same plane)?

So what rings do you recommend without breaking the bank.

And I also heard a lot of Leupold horror stories. I’ll need to research some scope test methods beyond RiverRider’s helpful mirror test if my re-mounting efforts don’t work. I really wish I had another scope to try but that not an option at the moment.

If you are referring to a trigger guard screw, my particular rifle uses the rear action screw to hold my trigger assembly in place.

First thing I did was check my bedding from action to stock and it still looks great. I bedded it last year and it still fits like a glove after a lot of use.

You need a mounting system that can be readily installed so that it doesn’t stress the optic.

What rifle/platform is this?

Ok, I see Browning A-Bolt 3.




First, check the rail to see that it is flat across the top. Check front to back and corner to corner. I use a ground bar, but you can use a machinists parallel, or any straight edge, that’s actually straight.

Then check the rail down the sides where the clamping surfaces come to a point.

Get yourself a set of Seekins 1” Lows.

Thank you for the response. I remounted scope and action as discussed earlier. My rifle has about 800 rounds thru it but haven’t seen carbon in the throat. I typically clean my rifle with “Ed’s Red” swab, bronze brush thru the bore guide, and multiple patches with mineral spirits pushed by a jag. But I did thoroughly clean it last month using the “wipe out” foam cleaner until I didn’t see any more blue copper residue. I don’t have any muzzle device and the recessed crown looks good. Bullets are not keyholing. And since I was working up new loads at the time, I very carefully weighed everything with two-scale verification.

That all leaves the scope itself so I may have to figure out how to rule it out.

Seekins 1” Lows

My money is on this being a scope problem, possibly exacerbated by the mounting system.

Check the rail as described above.

If the rail is straight, get a quality set of picatinny rings. Mount the rings and check that they are parallel and in the same plane with a quality set of scope ring alignment bars. If the bars have points, ignore them and use the butt ends. If rings are parallel and In the same plane, use an artist brush to dust ring to scope tube mating surfaces with powdered rosin. Gently blow off any excess. Place scope (use a different scope to verify rifle) in mounts. Adjust for ER and align reticle with bore axis. Then slowly tighten down screws, alternating side to side front to back, until you reach 15in/lbs. *Ensure scope reticle does not rotate out of bore axis when installing ring tops.

Thank you, Kingston, for your responses.

I didn’t use scope alignment bars because I didn’t think I needed that precision for max hunting range of 200 yards with 2.5-8 scope.

I did mount a new picatinny rail (“Weaver” brand in this case) a couple weeks ago - I bedded the rear mounting surface on the action and alignment is really good so I don’t think that’s my problem.

I would love to get the Seekins rings but I sadly cannot justify spending $100 on rings for this rifle. Those rings are lovely on your rifle, and I actually already decided I’m going to get them when I upgrade my rifle someday (that’s how I know they cost $100).

I fear that I have a scope problem

Read my edits/additions above.

You can’t assume anything. I had a crooked rail come through on a $1300 custom action a few weeks ago. It happens.

If your mounting system is tweaked, it will stress the optic, which can result in the optic failing.

It should be noted that the OP has had the gun shooting well already for hundreds of rounds. Then a sudden degradation in accuracy, not simply a shift in POI.

Something broke--that is your problem.

It is about 99% probable that it is the internals of the scope, since you did not find anything loose/broken/different with all of the screws/mounts/rails/bedding.

Get a different scope and try again. You will know immediately.

I removed the scope from its mount before I inspected it with the mirror.

I do try to be really careful when I mount my scope and I always torque rings at 20 in-pds as recommended by Leupold

Thank you. I will keep this in mind

I just inspected my scope with mirror after it was reinstalled on my rifle. I did not notice any shift after bumping the scope as discussed earlier.

Where are you located? You need another scope. That's great F'ing Avatar BTW, ohhh nevermind the big F is just on your profile... It'd make a good F'ing avatar rather than the quilt..

Warne makes horizontal Maximas now, the Mountaintechs and the Leupold PRWs. All domestic and resonable.

My location is typically Elizabethtown KY during the week and Indianapolis on weekends. I typically shoot at Knob Creek Range in Louisville.

Cool. Please follow up with us on any findings.... Folks generally recommend Burris FF2s for a budget scope if you need to go that way. Someone mentioned fouling. But 2 foot???? Dang.

I’ll definitely post whatever I find. Next step will be to give it another try at the range now that I’ve remounted and re-torqued everything - that will probably happen on Monday or Tuesday. Wish me luck!

Hello Frankk,
Do you understand how to check parallax? I've had rifles start acting crazy with Leupold scopes. When I checked the parallax at 100 yds, it was all over the place. On one scope, the crosshair was floating around almost 8", measured on a Redfield target with 1" grid squares. It was obvious there was something wrong internally. The parallax on that scope should be set at 150 yds. You shouldn't see much crosshair movement at 100 yds. Maybe none at all. Sadly this happened to me more that once.

Good luck,
Steve

Replace the scope

Burris Signature rings will alleviate any alignment issues unless they are extremely severe.

There isn't a lot to test on the scope without burning through ammo. If everything is mounted correctly and it still shoots crappy, take the scope off and send it to Leupold as that is most likely the problem.

Bedding is not going to cause that type of problem.. Some of these threads are just fu cking funny... Or "never not funny", to quote someone I've heard here....

My exact thoughts. I'd toss the damn vertical split fuggers in the trash can and at least buy a set of PRW's. There are a lot of great options (at many price points), that will fit on that rail... I'm very suspect of the rail mounting itself, as he says it was "glass bedded" onto the rifle. Not that glass bedding a rail is a bad thing, but I'm wondering if he actually removed the screws from the rail and action and checked every one to see if it was actually grabbing the receiver. Did he use longer screws in the area that needed the bedding? If it's not the scope (which I've had those (yes that brand) go bad a few times), it's the mounting system...

In the most complex of technical terms, I think your scope has simply schit the bed. Get some Burris Signature rings with the inserts and a new scope. Get the Leupold fixed and sell it. Happy Trails

You sound like a prime candidate for a Leupold executive...

Please let me know if you have something constructive to say. I’m not particularly advocating Leupold or anything else and I certainly did not intend to sound like that.

I would just like to solve a problem

I will definitely be looking for different rings. I really wish I saw some bad reviews about them before I bought them in the first place.

On subject of bedding I find the rail to be very straight but did see a tiny gap over back bearing surface when I only had front screws in place. The gap was almost but not quite large enough to shove a thin sheet of paper under it. I could have probably inserted all screws and be done with it but I wanted to do best that I could do. So based on friend’s’ recommendation, I applied epoxy under back bearing surface only and I only had front bearing screws in place when I did that. There is no gap now and all surfaces on a rail are flat. All screws were and are now again torqued at 20 in-pds with blue loctite. I’m not sure how else I should address that rail.

I too suspect it’s the scope from the sudden and dramatic shotgun pattern it’s shooting and your apparently eliminating the other possible causes.

I’ve had a Leopold back in the day that after a controlled fall with me protecting the scope as I was going down shoot a foot to the right at a 100 yds on checking it after missing a big bull at three hundred.

Should it turn out not to be the scopes fault which I think is quite doubtful, it’s never a bad idea to have an extra scope in the safe.

On subject of mounting, I previously had aluminum Talley Rings that bolted directly to the receiver with horizontal clamp. I purchased the rail and Warne rings to have adjustment for better eye relief clearance. So what does everyone think of those Talley ring?

I think most would agree that Talley Lightweights are okay, but if you need the flexibility of the picatinny rail I see no need toget away from it. There are plenty of good rings that will work on the rail. I personally like Burris Zee rings. I'm sure you're aware of the advantages of the Signature Zee ring, too. I use those myself on one particular rifle and they work fine.

Many folks have used Warne vertical split rings without issue for years. That is simply not the problem that'll cause 2 foot damned groups. He said they weren't all loose and chit.

I will not argue those that claim problems with them. I am sure they're convinced of it. LOL

Fugg the Chinmade Burris chit. Nobody needs commie crap.

I personally have no faith in Talley Lightweights anymore, but, many people have used them for years without discontent. LOL

Your scope is bad until proven otherwise, if you say everything was bolted up good.

Boomer, I don't think Burris Zee rings are made in China. If that's the case these days, I think I'd refrain from buying anymore. I know some Burris rings---I think they're Tactical Extreme, or some such, ARE made in China. They're okay, but I'd choose something else for that type of ring.

Whoa. They ARE made in China now. Damn.

I was just going to buy Low Burris Signature Zee Rings for 1-inch scope, but I cannot find any on amazon, midway, brownells or natchez. It seems that I can only get them for medium or higher.

I buy all kinds of Chinachit, but draw the line with new rings! LOL

Crap, I have ChinkoSwfas and Burrichows in use. Whatever.

We'll need the scope tested before blaming the mounts, no?


Why was the rail epoxied?

The XTR Signature rings are dandies, but wish they'd make them incountry.

My plan of action will be to give my rifle setup another go at the range next week. I have verified all mounting and action torques, and verified alignments as best I can. I’ll have to find another scope to try if I still have problems.

I do appreciate the advice about the vertical Warne PA Rings but I decided to make them work for me. I honestly don’t think any minor misalignments would have caused damage because I kept to the specified low torque, but I decided to check that alignment. So I made some alignment bars out of some good 1-inch bar stock (I have a lathe) and alignment looks good. I may decide to lap the rings at some point but I don’t think those rings are my problem.

Thank you all for your comments and please wish me luck going forward.

Talley LW’s suck.


Burris XTR (aka Horn) rings are retard high and made by the communists.

See above^^^^^

I have used the Burris Signature Zee rings ever since they first became available, they are my go-to ring on all of my rifles.
I have some that are U.S. manufactured and some that are Chinese manufactured and as much as it hurts to say it the Chinese made ones have a better fit and finish than the U.S. made ones.

drover

Damned Reds!

The XTR Sig is my go-to ring. I wish they made them in Low, but I make do.

I thought they are available in low now??

Lo mein?

Their lowest ring isn’t even in the same universe as the rest of the industry’s low rings.

Wi Tu Lo

It’s a Medium (1.00”).

Ho Li Fuc Wi So Fooni!


https://www.foxnews.com/world/organ-harvesting-china-survivors-victims

What's the problem with Talley LW's ? I only have one set mounted on a .223 and although they don't inspire confidence as to strength/durability they haven't given me any trouble. The rifle shoots .5 MOA with them and has been doing so for years.

Flavor of the week......

Nothing wrong with them. 5 years ago, they were the campfire rage, now they suck. Lot of Reeds shaking in the wind around here. Combine that with LOTS/MOST who don't actually do anything but run up their post count and "bobs your uncle", Talley's Suck.....

Not inspiring confidence might be a downside for the pessimist.

I must have gotten lucky with my last couple sets of Signature rings.

Not luck, just old stock. (Pure guess)

Things went well at the range today. Getting my zero again was easy and I have my typical 3/4 MOA accuracy again - so my rifle again seems more accurate than I am as it should be.

All I did was take everything apart, cleaned all surfaces thoroughly with solvent, and re-torqued all my scope and action bolts.

There are two things I don’t like about my Leupold VX3i 2.5-8x36 scope but holding zero doesn’t seem to be one of my problems. For what it’s worth, I think the scope actually has very nice glass and it’s generally easy to get behind but I don’t like fact that eye relief varies a lot with magnification settings. And this variable eye relief relates to my other problem of the scope not having very much physical tube area to clamp my rings on - I had to get a full length rail just to move the scope back far enough to get the eye relief clearance I wanted.

Thank you all very much for the good responses.

What magnification did you select for setting the eye relief to your satisfaction?

Hummmmm? Two foot groups from, what exactly?

I used the highest magnification for my scope (8x) to set position of my scope for the eye relief. I’m not sure how I can actually measure eye relief but there is a significant difference when it gets above 6x.

My new scope position still works fine for my hunting at minimum magnification (2.5x).

I didn’t have any groups when I had a problem last week. Points-of-impact varied randomly within 2 feet around the target dot from a distance of just 100 yards. It was a real mess.

My guess is I had a seating problem or loose bolt somewhere.

That's really odd, Frank...but I'm glad you got it squared away.

I think it's just as maddening to not know what you've done right as it is to not know what you've done wrong. I guess ya jest takes what ya gets.

I'm a long time user of that model Leupold. I've always set them up at 8x and the eye relief at lower magnifications has always worked out well despite the difference.

That’s a fact! I’m almost afraid to take out the action screws to give the rifle a good cleaning.

Torque screwdriver is your friend. Making sure all of the bolts are the correct torque, and dialing them to the same torque every time, will take a huge variable out of the equation.

I agree that a Torque Screwdriver is essential.