electro-polishing a barrel bore

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Although not PC correct, has anyone ever electro-polished a barrel bore? I read alot about lapping and steel wooling, cleaning jag with polishing compound, etc. Any thoughts?

 

[Zonie]

Electropolishing is, I believe, a reverse plating process.
It removes material from the part and deposits it on a expendable plate.

IMO, there are several things it will do, none of them good when it comes to the bore of a rifle.

Because it removes metal from the sharp edges first, it will remove the edges of the rifleing grooves much more than it will the surfaces. If it were used very lightly, it would could "break in" the rifling to reduce patch cutting, but if it was used "just a little" more, it would basically "wear out" the rifling before the gun was even fired.

Because it uses fluids and electricity to remove the metal, it will attack the ends (or mouth) of the bore and have very little effect further down into the bore.
(This is just the reverse of plating which tends to deposit the material at the mouth of the hole and deposits very little material further down in the hole.
Put another way, it would wear out the muzzle and the breech rifleing and leave the sharp edges down in the middle area of the barrel, still sharp.

Because this is a rather complex process, using special salt solutions (not table salt), it is not something the average person would be able to do. :imo:

 

[Chronos]

That is what I thought. The process was developed to clean welds of metal for use in HASMAT labs.

 

[Tahquamenon]

Actually, I've had these folks accurize an .223 AR-15 and an 30/06 M14 barrel that I had done after it was cryo-treated and the results were excellent.

The M-14's accuracy imroved by about 35% and the AR-15 improved about 20%.

Fouling was also reduced as well.

I've lapped more than a few barrels.

Were I shooting ML's for match accuracy. I would not hesitate an instant to have Black star electro-polish the bore versus me lapping one.
Also, I would have the barrel cryo-treated as well. Most of my pistols and many rifle barrels are cryo-treated.

I'm seriously considering having a couple of my ML barrels polished and cryo-treated.

Both of these companies are top notch! :thumbsup:

http://www.blackstar-barrels.com/body_accurizing.html

http://www.cryoplus.com/gunbarrels.html

:m2c:

 

Actually, I've had these folks accurize an .223 AR-15 and an 30/06 M14 barrel that I had done after it was cryo-treated and the results were excellent.

An M-14 in 30-06?

:shake:

I hope this was a typo!

 

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Did you notice much dimensional change? Did the muzzle bore have a bigger change in dia vs. the chamber end? What about the rifling? was it smoothed over or loose any of its' rifling sharpness?
It has been my experience that the change in dimension is in the order of one ten thousands(.0001), do you find this to be true?
Also, not just for cleaning up welds, it has many positive attributes. i had it done for some vaccuum chamber work to help get a cleaner draw down.

 

[Tahquamenon]

My bad typo - sorry.

M-1 Garrand in 30/06 not M-14. I have both rifles, but the M-14 is a 308.

:sorry:

 

[Tahquamenon]

Did you notice much dimensional change? Did the muzzle bore have a bigger change in dia vs. the chamber end? I did not have the bore's mic'ed, so I could not honestly tell you. The accuracy is better over a wider variety of bullets and loads and the fouling is reduced. What about the rifling? was it smoothed over or loose any of its' rifling sharpness? I did push a bullet through both barrels to observe the rifling cut. In both cases, the bullet engraving was still very sharp. But I've not a bore scope to look at the rifling under great magnification. To a visual, the rifling in both barrels appear sharp and distinct.
It has been my experience that the change in dimension is in the order of one ten thousands(.0001), do you find this to be true? Yes, I would agree. I did not mic/spec the bores either before or afterwards, but anytime you you lap or polish a bore you are removing material resulting in a dimensional change. Blackstar states that the maximum material removed during polishing is normally, a maximum of .0005 is removed from the land and groove diameters.
Also, not just for cleaning up welds, it has many positive attributes. i had it done for some vaccuum chamber work to help get a cleaner draw down.

 

[flashpanner]

thanks for your response! It is what I expected from this proceedure. :front: