New to rifles, "slugged" my barrels. Now what?

[F. Guffey]

No stories about a chicken that swallowed keys or whatever...

Whatever: The question asked by jimmy Dean had to do with the chicken crossing the road; it seemed there was an interest in 'Why the chicken crossed the road'. Jimmy said the obvious answer to the question was to show the opossum it could be done.

And then there was the question about the chicken dipping snuff; I said if I tell you the chicken dips snuff, don't argue. All you have to do is catch that little pullet and look under its wings to determine which side she carries her can.

Back to the OP's question; he wants to know how to accurately measure the slug. And there was a question about the accuracy of the slug.

I have Br'er Rabbit barrels, those are barrels reloaders got cute and or fancy with methods and techniques when checking the diameter, I also have a few barrels that are rendered scrap by smiths, no way to determine what caused the problems because I can not get an honest answer. One barrel has a stuck bullet, stuck jag and a drill that sheared off when he made an attempt to drill the jag. I asked him how the bullet got between the jag and drill bit.

F. Guffey

 

[RC20]

OP: I am glad you think you have your questions answered but if you look at the cross diagram on a 5 grove barrel I supplied you can see how iffy that is to measure.

It seems I have scored a clear miss on the 50 yard target, sigh.

I will take this into the philosophical realm as at my age that is becoming important, if only to me.

It seems to bother you more than it bothers me, I do not approach problems like they are complicated and or 'just can not be solved'. For 10+ years I have been told how difficult life can be when the rifling comes in odd numbers. Measuring the two diameters of the barrel does not change for me when I go from 2, 3, 4, 5, 6, or 7 etc., and then I have one barrel that looks like hair.

Mr. Guffey:

Could you then explain the very narrow window of being correct for the 5 grove diagram?

Yes, I have come to think you have a lot to offer, so yes it bothers me. Being able to express and pass knowledge on in a coherent and straight forward manner is what a legacy is about. Once we are gone, all that is gone as well unless its passed onto others. Knowledge can live on forever.

I am sorry we can't meet in person, it would be one if not the most interesting interactions of my life I believe.

I would hope it would bother you as well, but that is just a hope, I can only speak for myself.

Where I work when I am gone, I can see it even now, the deviation of it that you have to bring back to what is right is an on going battle. That is why the good story tellers were so honored before print, they accurately and clearly passed on hard won knowledge.

The communist party used to have an ideologist to keep it all straight so that a running dog capitalist did not become something endearing and warm and fuzzy animal thorough drift.

Just my thoughts.

 

[JeepHammer]

Mehavey is closest.
The 'Bore' is the hole in the barrel blank.
For instance, .223 is a .218" bore blank before rifling grooves are added.
A pin gauge is how most smiths determine initial bore diameter.

Personally, I start with an undersized bore, do a smooth hone to proper bore size so I know I've removed scratches and have a round bore,
Then cut rifling.
It's pretty easy to determine rifling depth on the broach (cutting tool that cuts the actual rifling is called a broach)...

Not that gauging the rifling is needed a lot anymore with modern equipment...
Older, particularly military barrels should be inspected/gauged if you have issues, military production was often done on old, worn tooling & fixtures,
Modern barrels are often produced on CNC equipment and have superior QC equipment for checks, so not nearly as many issues as we had back in the day.

A good bore scope is a wonderful thing, any actual gun smith should have one.
On the older rifles in particular, look for the rifling to start straight, then wobble a little before it starts to spiral evenly.
This is a sign the chamber was cut before rifling, A bad way to do things.

When the rifling is cut first, the chamber reamer removes the loading/unloading start of the rifling broach.
The start up load on the broach often causes problems with rifling depth requiring lapping to even things out.

Hammer forging rifling will cause 'Chokes', tight spots or large spots in the bore/rifling.
When hammer forging is done EXACTLY RIGHT it's hard to beat,
It's easy to do wrong, and it's FAST to make barrels hammer forging, so during wartime there were a lot of hammer forged barrels that aren't quite 'Right'.

This brings in the air gauging process for bore/rifling check,
And about all of us have seen the pictures/video of the press operator STRIGHTENING barrels by eye...

With modern equipment, the bore *Should* be straight to start with,
With pulled broaches, the bore/rifling *Should* be correct.

Now, keep in mind you can buy an AR barrel for $20 (or less) in bulk, made in China, bore off center to the outside profile, rifling wonky, chamber no where close...
I'm talking a reasonable quality barrel made in a country that doesn't use slave labor!