# Indexed barrel?



## trad1 (Jun 26, 2018)

Had my marlin 1895 guide gun sent back for repairs due to accracy.They had written on the paper work that they indexed the barrel,what does that mean?


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## james243 (Jun 26, 2018)

That probably means that they made a mark on the barrel and receiver prior to removing the barrel in order to put it back together with the barrel oriented the same way relative to the receiver.   Maybe they removed the barrel and recrowned it in a lathe.


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## jmoser (Jun 27, 2018)

Could also mean that they set the bbl back and rechambered; have to machine carefully so the front sight stays exactly at 12:00 when it is threaded back into the receiver with proper torque.

A bbl with no sights on it would not need to be indexed.


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## trad1 (Jun 27, 2018)

Is it possible to rerifle a barrel?If so seems it would weaken it.


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## JackSprat (Jun 27, 2018)

trad1 said:


> Is it possible to rerifle a barrel?If so seems it would weaken it.



Several people around the country specialize in doing that.

Think about it -

Go to  a custom barrel maker site.  Look at all the configurations.  Most common calibers use the same shapes.

There is no difference between rifling a barrel from the get -go in ..375 Winchester and reboring a .30-30 barrel to the same caliber.


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## rayjay (Jun 27, 2018)

jmoser said:


> Could also mean that they set the bbl back and rechambered; have to machine carefully so the front sight stays exactly at 12:00 when it is threaded back into the receiver with proper torque.
> 
> A bbl with no sights on it would not need to be indexed.


No way to do this on a lever action with a tube magazine.


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## Jester896 (Jun 27, 2018)

usually if a barrel is "shot out" it's replaced.  Indexing could mean a couple of things, but it is basically centering something in most cases like mentioned above.

If it had a throat issue they could have done it the way jmoser spoke of...just the beginning of the rifling has an issue.  A machinist/gunsmith can figure out how many additional threads are needed...index it...since it does have sights on it...cut the threads and remove material from the end of the barrel as needed for proper clearances and then screw it back in so that the writing is where is is supposed to be and the sights line up where they are supposed to and re-cut the chamber back to spec.

indexing could also mean finding the center of the bore when the barrel is in the lathe so that all work is done with the bore centered in the lathe or if there is a good curve in the rifling they can figure out where it needs to be to get the curve in the correct vertical position for the rifle to perform better or properly.


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## rayjay (Jun 27, 2018)

To the op, I think you are being baffled with bovine excrement. Probably some inexcusable oversight in production was the cause of your issue so they came up with some BE .


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## jmoser (Jun 28, 2018)

http://www.marlinowners.com/forum/marlin-rant-forum/72195-receiver-barrel-alignment-1895-1894-a.html

Read the link and tell me what you think then.

Indexing the bbl means just that - could be they merely corrected a minor misalignment [or possibly just verified the correct indexing.]
Very very common on revolver gunsmithing jobs and not a big deal.

Always needs to be indexed so the front sight is at 12:00, also some of the tube mag guns have a bbl cutout at 6:00 for the tube hardware.


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## rayjay (Jun 28, 2018)

Sounds like an inexcusable oversight to me. There is not a huge range of torque values for this threaded joint. If the dovetails are not properly aligned at this torque then you are either going to over-torque or under-torque the bbl to "fix" it. Also, due to the size of the thread there is not a lot of rotational difference between under , over and just right.

If the bbl needed to be screwed on an extra few degrees then it would be possible to move the torque shoulder forward enough to do a good job with the repair. If the bbl needed to be unscrewed a few degrees to fix the problem then a new bbl is the proper repair.


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## jmoser (Jun 29, 2018)

You almost never 'unscrew;' you machine off one full thread and screw in.  That is when chambers may need to be recut etc.


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