Signs That A Scope Has Gone Bad?

[gilream]

I'm getting a lot of erratic groups with my 6.5 X 47 Lapua. Used to be a tack driver. Pretty much eliminated anything else. Many times it strings in a diagonal or horizontal direction other times it puts 3 in a group and two together someplace else. End of my rope. For those with experience, what happens to the groups when a scope goes bad?

 

[john 800]

Here is my experience with failed scopes: two had massive point of aim shifts, one after being dropped one for seemingly no reason. Off by multiple feet at 100 yds, not inches. Also had sevral that would not track well or at all, then sometimes the group would move all at once including previous adjustments. When they start to act weird I try a different scope, I don’t give them much time. I have had a rifle with a bedding issue act similar to what you describe, it was a rem 700 varmint barrel laminate stock model that I had a gunsmith bed the action. The bedding was to tight around the front amd sides of the recoil lug and the first few inches of barrel was bedded. I releved the sides, front and bottom of the recoil lug and the bedding under the barrel. This rifle was shooting a bit under 1/2 moa and was throwing fliers maybe 3/4” give or take out of the group at 100yds, sometimes clustering a few together sometimes not.

 

[tharger]

I had one, would throw shots only about an inch. every which way. was previouly a good shooter. changed out the scope, fixed

 

[Eagle Six]

As others have stated, swap out the scope, or swap out the rifle to this scope. Then you will know if you can eliminate the scope as the problem or the scope is the problem.

 

[K22]

I never had one that went bad but a friend of mine did, at least that's what we determined. A bad scope was the last issue I considered because I had never positively seen it before.

All of a sudden, after years of faithful service, his rifle would not hold zero. It was a hunting rifle but previously a 1 moa rifle. We tested it off a high-quality front and rear rest. Two shots would be off zero but close together. Then the shots would shift several inches at random. It was extremely frustrating. After assessing as much as I could, I suspected a bedding issue but that didn't make sense either since it shot well for years, and nothing could be identified as changing the bedding. Also, there were not enough rounds through it to suspect that the barrel gone bad. It was 308 Win which isn't hard on barrels anyway. He is not a target shooter, just a hunter an puts about 20 rounds a year through the rifle.

Just for the hell of it, I put one of my spare Leupold's on his rifle and bingo, the groups returned to normal. I shot a couple of sub-1 moa groups with good factory ammo.

This was the only case I ever encountered in 50+ years in this sport but it was undeniably a scope that went bad, probably due to rough handling during tough mountain hunting.

Ron Spomer wrote an article about this, and he described scope failure attributes as follows:

1. Reticle doesn't move when turrets are changed.
2. Reticle out of focus
3. Reticle titled to one side off center.

Interesting enough, my friend's scope did not exhibit any of these characteristics. That is one reason why it was so difficult to narrow the problem down to his scope. So, I would try another scope and shoot a few groups off a solid bench rest to see if you can either eliminate or identify the problem as the scope.

 

[Jeff Porter]

Had it happen today. Consecutive shots without touching the knobs.

 

[Jeff Porter]

Swapped scopes - same load.

 

[Steve Blair]

Signs a scope has gone bad:
- Hanging out with the wrong crowd
- Blurred view and unresponsive to input
- Sudden behavioral changes
- Empty packs of cigarettes in the gun case

 

[Coyotefurharvester]

Zero shift, erratic or irregular turrent(tracking) adjustment. Scope will not focus. Zero shift(poi) when decreasing,increasing magnification power. Parallax shift(reticle image moves) from repositioning your eye cannot be eliminated.

 

[DirtySteve]

It is your mount... Check every screw in your bases and rings..

 

[john 800]

Signs a scope has gone bad:
- Hanging out with the wrong crowd
- Blurred view and unresponsive to input
- Sudden behavioral changes
- Empty packs of cigarettes in the gun case

Next thing you know there is money missing from the dresser and yer daughter is knocked up, seen it a thousand times

 

[acloco]

Run a box test.

Shoot ONE shot at 100 yards.
Move UP 1" and Right 1", shoot.
Move DOWN 2", shoot.
Move LEFT 2", shoot.
Move UP 2", shoot.
Move Right 2", shoot.

Should end up at the same place you started. High 1" and Right 1".

 

[Sandstorm]

Empty packs of cigarettes in the gun case

Out all night ..and sleep all day.
Yea id find another one if I were you.

 

[JFrank]

Next thing you know there is money missing from the dresser and yer daughter is knocked up, seen it a thousand times

Your lawn mower and chainsaw is missing.

 

[Forum Boss]

I had a Leupold 8-24x50mm scope go bad in the middle of a 600 yard match. I was zeroed within 3" on steel.

First record round went into the target center just outside the X. Second round went into DIRT below target frame. Third round -- not sure, but did not appear on target. Fourth Record Shot went OVER the target and kicked dirt on back of berm high.

I stopped the match. The next week send the scope back to Leupold. 6 weeks later I got the scope back with a paper saying Leupold had pretty much replaced ALL the moving parts inside.

So what I observed was Point of Impact changing by 3 feet or more (6' total) at 600 yards.

 

[fkimble@charter.net]

Signs of a bad scope will vary depending on what part inside goes bad. It's not a one symptom deal. And it is not always the scope. Consider rings, bases, ammo, shooter, dirty barrel, ammo lot change, component lot changes. The list is long.

Frank

 

[SteveOak]

• getting tattoos,
• hanging out with unsavory characters,
• challenging rules and directions
• talking back
• moodiness
• seeking independence
• staying up late and sleeping even later
• taking occasional risks
• identity confusion
• experimentation with clothing and hair styles
• being argumentative

 

[Uthink Uknow]

Hmm. No one has heard of the Hood Scope Checker? Charlie Hood built and sold this item few years back. We have two.
You remove your scope and mount the scope checker on the dove tail. Mount the suspect scope on one rail and a good one one the other rail. Fire a shot and adjust the good scope to POI zero, Then move the suspect scope to exactly the same spot. Shoot a few more shots to confirm your zero and check to see if the suspect scope if the two scopes are still properly aligned.

 

[LHSmith]

I used a scope checker made by Mike Ezell. Using it in conjuction with a proven high magnification scope it showed that the 45x scope did indeed shift POA with every shot from a 6PPC bench gun. The movement was very subtle and I may have went through several matches until I addressed the real problem.