Here’s some advice: DO NOT OWN ONE unless you’re a metallurgist. What you see will not make you feel any better. It will confuse and scare you and will ruin the fun you could have shooting. Just because you’re curious is not a good reason to start examining things you simply will not understand. When you need a bore scope, you’ll be taking the gun to a gunsmith who will already have one and he’ll know what he’s looking at.
I answer this question easily once a day and it’s always the same answer, “Don’t bother. Just shoot.” The times when I might have answered differently were answered with, “Dude, your shit is busted. Take it to a gunsmith.”
There. I either saved you $25 or quite a hell of a lot more. You’re welcome.