Borescope results?

[cdhknives]

I actually recognize that problem! If I approached the 'which scope is bad' issue the same way I do control and instrumentaiton failures in my normal (engineering) job, there are several solutions. 2 out of 3 checks are the quickest, mount 3 and see if 2 agree. Odds are VERY high the odd one out is the bad one, or at minimum you see 3 different results if 2 (or all 3) are bad. Otherwise process of elimination works. 3 scopes, compare 2, different readings, swap one, check again, still different==one that stayed is bad, read same==one swapped out is bad. It helps to have a known good (or at least trusted) instrument for reference. Or to put it another way, if A=/=B and A=/=C and B==C then B and C are good, A is bad. Classic 2 out of 3 testing for failure. That is a lot easier for us laymen than building a locked down scope for the testing. I could mount a couple of rails on a single heavy aluminum block for comparing, I could not dissect the internals of a nice scope for such an operation!

 

[Papa Charlie]

You can get an idea of the scopes POA accuracy by doing the box method of testing also.

Example:
First shot is your baseline Elevation and Windage at Zero or where ever your starting point is
Second shot Elevation Zero, Windage to -5 (Left) minutes
Third shot Elevation -5 (Down) minutes, Windage unchanged (-5 minutes)
Fourth shot Elevation Unchanged (-5 minutes), Windage back to Zero
Fifth shot, Elevation back to Zero, Windage at Zero

You should end up with a perfect square and last shot should be very close to the first shot, same hole would be perfect. Of course best to perform this and any testing on a sled and in calm conditions. I like to do testing as early as possible in the morning when wind and heat are not an impact. It is not unusual for me to get all set up and have a wind come up and that will cancel this type of testing. Essential that you have good loads that are not going to add impact to the out come. I will generally perform this test on my competition rifle for friends to check scopes when they are having issues.

 

[Earl]

They have talked a lot about those over on Accurate Shooter, it is my understanding that just like our test equipment, you need to have one scope that has been locked so that the reticle cannot move. They were sending scopes out to be modified for this purpose. Then you could be assured that the point of aim will not move and provide accurate measurement of the subject scopes movement.

Never used one, so this is from reading the threads on the subject.

I have had scopes (yes - more than 1) that were "frozen" by a well known (for his scope work) Gunsmith. They were great for a year or so. I didnt know the reason my shooting took a nose dive. I could not get to the top 10 in any match I attended. I change barrels, bullets, powders, guns to no avail. I was at a match and could not get my gun to shoot. A buddy loaned me his spare gun. I put my barrel on it and proceeded to place 3rd in the match. The next week I put that barrel back on my gun and could not get it to shoot. I finally put one of my old scopes on the gun and bingo! It was almost a year that I struggled. It was because my "known good" scopes were moving on me and I did not recognize it as a bad scope. Perhaps it was the heat in Phoenix the caused the glue to come loose. I dont know. I now regularly test all of my scopes on my unlimited rail gun. I put the cross hairs on a known spot on the target. I shoot 10 or more shots and then insure that the cross hairs are on the same spot. I realize that not everyone has a rail gun available but it sure makes it easy to weed out bad scopes.

 

[Earl]

I have had scopes (yes - more than 1) that were "frozen" by a well known (for his scope work) Gunsmith. They were great for a year or so. I didnt know the reason my shooting took a nose dive. I could not get to the top 10 in any match I attended. I change barrels, bullets, powders, guns to no avail. I was at a match and could not get my gun to shoot. A buddy loaned me his spare gun. I put my barrel on it and proceeded to place 3rd in the match. The next week I put that barrel back on my gun and could not get it to shoot. I finally put one of my old scopes on the gun and bingo! It was almost a year that I struggled. It was because my "known good" scopes were moving on me and I did not recognize it as a bad scope. Perhaps it was the heat in Phoenix the caused the glue to come loose. I dont know. I now regularly test all of my scopes on my unlimited rail gun. I put the cross hairs on a known spot on the target. I shoot 10 or more shots and then insure that the cross hairs are on the same spot. I realize that not everyone has a rail gun available but it sure makes it easy to weed out bad scopes.

I neglected to mention how we used "frozen scopes." There were so many problems with scopes moving, that a gunsmith (dont remember which one) made adjustable rings - rings with micrometer type adjustments. This actually just moved the problem from inside the scope to outside of the scope. I will look and see if I have a picture of one. Weird looking scope - no turrets. They were removed and flat plates were installed in their place.

 

[Earl]

Frozen scope

 

[Liljoebrshooter]

I think those are Bob Brackney mounts. I had a set of Buckys mounts and a frozen scope. They worked but they were a pain to move your POI.

Joe

 

[Papa Charlie]

You make some good points. Just because our equipment performed yesterday, does not mean that it won't have issues tomorrow. They are mechanical devices and things will break. I hear all the time when someone hears of a scope malfunctioning that, that is why they buy the expensive ones. Well I got news for them, every single scope, I don't care how expensive, has the potential to fail.

On the other side, I have had other shooters claim that their scopes must be broken because all of a sudden it isn't shooting right. In this sport, there are literally dozens of things that can cause this. More often as not, it is something small, a change in procedure, improper cleaning, reloading issue, and of course there is the loose nut behind the gun.

Part of what can make this sport, whether BR, F-Class, PRS, etc, frustrating and exciting at the same time.

Good shooting Earl. Enjoy!

 

[Earl]

I think those are Bob Brackney mounts. I had a set of Buckys mounts and a frozen scope. They worked but they were a pain to move your POI.

Joe

Yes, those are indeed Bob's rings. I do believe that Gene was the one I was trying to think of. He may have been to first to sell them. It was somewhere around 2005 - 2006. We were having issues with lots of scope brands. Bob is local here (Wickenburg). We are in the same club. Bob is the only Bench shooter that I know that shoots a Remington 700 action. His does a good job on those things. He hasn;t been to the range much this year. He is coming back from a knee replacement. I dont know his exact age but I know he is in his 80's. Another shooting buddy of mine went up to see him last week and said he is looking forward to the upcoming season.

 

[Liljoebrshooter]

Wickenburg? You don't run with that outlaw Chuck Miller do ya? Hehe

Joe

 

[Earl]

Wickenburg? You don't run with that outlaw Chuck Miller do ya? Hehe

Joe

Me and the Chuckster are good friends. He likes to tell my wife that if she had any money, they could run away together! I believe that Chuck and Dan Sutton are going to Raton later this month. Chuck has had his share of medical issues but just last Thursday, he was out at the range delivering a barrel that he fluted. I am going up to see him later in the week.