Bore Horny!

[RamRoddoc]

Or my Redneck Chamber Polisher....and for the German's Shweiny Geil zehn millimeter polisher.

I read on the webs where you could polish your own bore with little more than a drill! Get out of here. Well I do have two new isonite processed barrels that are too tight for my reloads despite new brass for the zehn millimeter.


So the first task is finding a correct size drill bit.

This one seems to fit. It's getting interesting.

Well once you get a drill bit duct tape it up so it fits snug and no metal to metal contact can occur.

Now push it through the bore, it should be tight but not where you need to hammer it. Once it comes flush with the chamber, stop. This will prevent hosing up the chamber when you get to drilling.

I grabbed a .357 Magnum (fired) and drilled the hole just big enough to allow a cleaning rod tip to go through but not the whole rod.

I used a hackem up saw and just drawed the blade back a few minutes and cut the case center mass.

I marked the .357 Magnum case when it hit the end of the chamber, to know how deep to cut the case.

A cleaning rod, a few washers as spacers and a cleaning rod attachment on the inside of the case and it looks like this might work?

You're going to put that where....eeeek!

I kept the speeds low to mid and when it became uncomfortable to hold, took it out and hit it with compressed air then checked it. The metal was freaking hard as heck and this took several hours.

More to follow......

 

[RamRoddoc]

The red neck chamber polisher took a bit of time to do its job. After a a couple of minutes a virgin empty 10mm case dropped right in. I ended up using 100 grit to get the loaded round over 8/10ths in the chamber. Then went up to 150 grit for a bit and then 220 grit. When the round finally popped in with gentle pressure (it was that last 1/8" that was the issue). I actually shortend the paper width as to polish deeper since the chamber entrance seemed fine. I was also able to wrap a bit more paper around the case to put more pressure on the chamber for a more effective polish. Once I was thought it was good to go and the slide/recoil spring should be able to send it home, I stopped and used some 400 grit to polish the entire chamber surface.


A nice polish on the feed ramp often aids care and feeding. A fresh 10mm case works well with some 220 grit wet/dry sandpaper.

The first function check and the round failed to feed correctly stopping about 1/3 of the way in the chamber-nose to the top. I broke the "hump" some more at the 6 o'clock and 12 o'clock postion with some 150 grit then polished it with 220-400 grit sandpaper.

There were scuff marks on the breach face of the slide and the the surface was textured-sandblasted. It really needed a bit of polish too, just below the firing pin was where it was scuffing/hanging up.

Once back together this gun fed and chambered fine. Now it just needs a shooting but there is still more left to be done..... That will be yet another day and another thread gentlemen.

 

[Hayata]

How much material do you think you need to remove? Is it a polish, fit, repeat type process or is there a target measurement that you are attempting to meet? Either way, good luck and keep the pictures coming!

 

[RamRoddoc]

How much material do you think you need to remove? Is it a polish, fit, repeat type process or is there a target measurement that you are attempting to meet? Either way, good luck and keep the pictures coming!

Just enough metal to reliably feed my 10mm reloads ran through my dies. Basically it is a hand fit chamber to my rounds. It should make it very accurate or at least the potential. Yes a lot of stopping, compress air, fitting a round. I used a fired case to get me close then the last 1/3 of the work was pushing the bit down so to allow the round to chamber-or attempt as it was until enough metal was removed to allow it to fit.

 

[Clarke123]

Wow!

That's taking the bull by the horns!
I've used Mother's Mag Wheel Polish to polish feed ramps and to remove tiny scratches from stainless steel, even 400 / 600 grit to polish out deeper scratches (before using Mother's as the final polishing step), but never anything this daring!

Applause: Good Job!

 

[drjterrell]

Love it! Great ingenuity.

 

[loadnplenty]

That's cool and very interesting!!

 

[Clarke123]

When you do your posting on the results, please include "Do's" and Don'ts" regarding having a barrel processed with Isonite.
It appears that the chamber was coated to the point of being out-of-specification, but did that also include the bore as well?

Realizing that the earliest Christians met the hungriest lions, and the earliest pioneers are readily identified by their lack of hair and
the preponderance of arrows sticking out of their backs .... I ask the question out of respect for your experience (realizing that such experience is often earned
the hard way and usually evidenced by the number of arrows sticking out of one's 6 o'clock)

I really don't know anything about Isonite, and appreciate your sharing what you know about it. There are also other metal "treatments" out there that keep showing up, always with glowing testimonials, and you wonder just how "wonderful" they really are (and whether you are just buying some more expensive Medicine Show "bear grease" or perhaps a dose of "t-r-o-u-b-l-e")

I know that I've had slides, extractors and even fine-pitched screws CERAKOTED and was initially concerned about "fit", but was pleasantly surprised to find that even the extractor and screws fit back into their "holes" without binding; and functioned perfectly.

BTW: Thanks Again for your excellent posting as well as your history of providing a lot of people with valuable information!

 

[RamRoddoc]

Clarke123,


The isonite processing as best I can tell adds 0.0002" and if you consider a chamber/bore that adds up to 0.0004". I doubt that alone is the issue as long as what I have learned is the truth.

I suspect newer tooling or a production line chamber dimension tolerance change lends itself to become an issue at least for me. I have contacted both the group that does the isonite process and a Storm Lake representative. The older 2008 raw stainless Storm Lake barrel while exceptional in tolerances will accept quality reloads that are within specification. I measured them to be sure.

The bore would have to slugged to see what the actual diameter is, not something I will do unless I see issue (accuracy or excessive leading).

The isonite process of salt bath nitrocarburizing (isonite) has been around a while. I swear that the bolts I pulled out of many M16 A1/A2's look to have the same finish. I can say that the process really does harden the surface greatly and improves resistance to wear, tear and pits. When I fit the hood of the G34 to the slide (the 10mm fit perfectly) the resistance to the file was duly noted.

http://www.trutecind.com/isonite.aspx

I wouldn't order another Storm Lake or really any match barrel without an expectation some minor fitting. My experience with the 2008 barrel was such that I didn't expect it. A new guy buying a barrel might not be aware of what "some minor fitting" really means and may be over whelmed initially. Fitting is not a bad thing and actually insures you gain the most in accuracy. It does often come at a cost besides the fitting and that would be total reliability. Match grade and combat worthy are too separate issues that can meet somewhere in the middle.

I have done some homework on Cerakote and it does seem superior to many of the coatings. I ordered some yesterday with some Aluma-hyde from Brownells. In a week or two if my date with a milling machine comes through I'll post up something fresh.

I'm reasonably ignorant about far too much but willing to listen and learn a thing or two. Thanks for your input sir.

Lastly a pearl; when polishing a feed ramp the machine lines will make themselves known. Don't change the angle or go all the way through the machine marks. Rub your finger over the ramp prior-during and after then it's easy to see why it’s beneficial. Don’t' polish Aluminum feed ramps! The aluminum is surface hardened and a polish job can easily remove it and expose the softer metal.

 

[acmech]

Excellent work, glad you got it straightened out!