Borescope Help

[timeout]

Thinking about getting a borescope. Are there any good training aids available that show what the various internal barrel issues look like when viewing the scope? When I first started my career as a mechanic (back in the stone ages), Federal Mogul had a very good pictorial on bearing failures. Something like this is what I am searching for.

 

[Rustystud]

Look at the Gradient len web site. Dan Lilja on the Lilja barrels has a pretty good video on comparing a factory barrel to a custom barrel.
Nat Lambeth

 

[TheSnake]

Agree with Nat and there are quite a few videos on YouTube. You could also give a local smith a call and see if he is wiling to take a few minutes to show the the basics when your scope arrives. The local smith in my small town is very nice and spent an hour with me in the shop when I picked up my last job answering questions.

 

[timeout]

Thanks for the replies gentlemen! I will check out the videos and website.

 

[DanCarey]

What you can see.

 

[spclark]

First time you 'scope a bore you'll be SHOCKED I swear by what you see. Getting over that is a matter of time and experience.

One warning: these things are FRAGILE despite their fairly robust appearance. Take every precaution to keep them from flexing AT ALL whether during use or just in handling. There's more in that skinny tube between the lens up front and the eyepiece at the back than you'd ever think could be packed into such a skinny pipe. Not impossible to put right after you find it non-functional some day but not cheap either.

 

[timeout]

Interesting photos Dan. Would you care to explain what they show? I watched the video on the Gradient Lens website. What I saw on there was a little more as I expected. The ones you have displayed here appear to my untrained eye, to be a fairly new bore with some funky markings made during the barrel manufacturing process.

 

[DanCarey]

You have that part right, they are all new stainless barrels. Shilen, Savage and Olympic Ultra Match.

 

[GerryM]

First one shows plenty of reamer marks the second a hand lapped barrel the third a barrel that has a few marks lefy ad the 4th a almost finished lapped bartrel with some type of solvent on one spot from what I can see.
The first one is pretty rough and should foul pretty easily, The second shood shoot good groups and scores. if it a uniform diameter.
The third should shoot fair but would foul after a while
The forth looks ok but it might foul at aslower rate. that too should shoot fair to good.

 

[DanCarey]

The 1st barrel is a Savage, the marks are uniform, meaning they were made by the deep hole drill.

The second barrel is a SS Shilen.

The 3&4 are of the same barrel.
They shows tears, reamer marks and some drill or chatter marks. I wouldn't stick my borescope in a barrel without running a couple clean patches thru it first. So there is no solvent or oil on the lands. Those are tear marks.

 

[timeout]

The 1st barrel is a Savage, the marks are uniform, meaning they were made by the deep hole drill.

The second barrel is a SS Shilen.

The 3&4 are of the same barrel.
They shows tears, reamer marks and some drill or chatter marks. I wouldn't stick my borescope in a barrel without running a couple clean patches thru it first. So there is no solvent or oil on the lands. Those are tear marks.

Thanks Dan! Very interesting.

 

[GerryM]

From what i see its looks like 3 and 4 are a photos of the barrel being lapped\
look closely and you will see very slight marks going lenght wise down the barrel
It may be the barrel at different stages of lapping. if its the same barrel, at different spots left this way, it,s a mess

 

[DanCarey]

Picture number 3&4 are of an Olympic Ultra Match stainless broach cut barrel. It is NOT lapped. The marks you can see are caused by the broach.

This is a barrel cutting broach. WW-2 technology

 

[fdshuster]

timeout: Don't be intimidated by the Hawkeye borescope. In a very short time and after looking into different barrels you will quickly become familiar with the "good, bad & ugly".

All you have to see is one of the hand-lapped barrels, made by several big name makers & a sub-quality barrel will be easily identified.

The pictures Dan posted are excellent / wish I had the ability to do the same.

 

[timeout]

Thanks for all the help. You guys are top shelf!

 

[GerryM]

where did those marks going lenght wise come from?. looks like a barrel that was lapped to some extent. was the hole lapped first? thats an awful fine finish.
But a reply is correct after you see a hand lapped match barrel you will know what a clean match barrel looks like.
After you shoot a match barrel, you will be able to see just how clean you are getting it. Your going to get a surprize. you will see carbon tracking , fouling from copper and possably corosion if your not cleaning the barrel correctly.
I know a scope is kind of pricey, but after you get use to haveing one you will wonder how you ever did without it.