Mythbusting? Can a bore be too polished?

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Canuck Bob posted this 05 December 2014

I've bumped into varying opinions regarding this topic.  To be clear I'm not referring to bores ruined by polishing or lapping.  For discussion lets consider a healthy polished bore for cast primarily.  If it is different for jacketed that is worth discussion too I suppose. Confirmed or Busted.  Folks who firelap, handlap, and use other techniques like Onondago's snake method often talk about reduced or eliminated leading and cleaning after polishing.

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onondaga posted this 05 December 2014

http://www.castbulletassoc.org/view_user.php?id=4124>Canuck Bob

The physics of polishing relies on grit size, applied force and velocity of the polishing instrument doing the work. I limit the grit size to 500 with the Chrome polish I recommend and I limit the pressure to the fit of the BoreSnake and I limit the velocity of the BoreSnake with abrasive to the speed of hand pulling.

It is easy to use even a coarser grit than 500 with the force and higher velocity of fire Lapping and end up in a situation removing substantial bore metal. That is not polishing by definition and easily capable of damaging bores when done carelessly.

A reasonable harmony needs to be met with what you use and how you do it to help a bore instead of ruining it.  You would really have to be an aggressive odd bird to ruin a bore with a BoreSnake and Turtle Wax Chrome polish and Rust Remover. Review my Bore Polishing Method and instructions  at:

http://www.castbulletassoc.org/viewtopic.php?id=8364&forumid=63

Gary

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onondaga posted this 05 December 2014

Joe B believes a bore can be over polished and cause lead to stick to the bore. He can support that with historical references too. The support he sites only shows me that anybody can overdo anything to the point that it is just wrong and not relevant because it is a deliberate error to prove a point and not constructive at all.

Gary

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gpidaho posted this 05 December 2014

Out of just dumb luck my new 24” 223 Handi may have had the barrel cut to a reasonable quality to start with, but for the first time I tried Gary's bore conditioning technique. The little rifle shoots much better than you might expect for $300 and clean-up is a breeze. I'll do it again on the next barrel I want to break in. Thanks for the tip Gary, works for me. GP

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Ed Harris posted this 05 December 2014

I agree with JoeB that ultra-smooth microfinished bores foul worse because you get increased bore drag in the same manner as dragging a pair of gage blocks against each other or fusing prisms together through their surface adhesion.

I once had an HK hammer-forged 7.62mm polygon bore which gave very high pressure signs and hard bolt lift firing 168-grain M852 Match ammunition until it was lapped with 320 grit and then the pressure signs went away like magic!

73 de KE4SKY In Home Mix We Trust From the Home of Ed's Red in "Almost Heaven" West Virginia

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onondaga posted this 06 December 2014

http://castbulletassoc.org/view_user.php?id=207>Ed Harris

The 500 grit chrome polish I recommend pulled at hand speed on a BoreSnake will not over polish a bore so shiny that lead will stick to it like fusing prisms or gauge blocks. That is an example of abuse like Joe has used in his unproductive argument. The chrome polish pulled at hand speed for 100 strokes per instructions does not make a barrel bore surface like prisms or gauge blocks,  it hand polishes the metal to a 500 grit hand polished finish that lead doesn't readily stick to and leaves the bore polished and easier to maintain.

How many of you members are going to line up and beat a dead horse here? My polishing method does not over shine a bore. It is a hand polishing method with a gentile abrasive. The instructions are simple, they don't say use 1,000 grit abrasive and pull it through 2,000 times with a power drive at 300 feet per second and ruin your barrel.

Face it, there are people that think they are following instructions for fire polishing when they dip their bullets in glue and roll them in beach sand before firing them. These are the people that will condemn fire polishing as effectively as the invalid arguments against my Bore Polishing method.

Gary

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Ken Campbell Iowa posted this 06 December 2014

the closest thing to interesting that i can input is that i had a rimfire 40x barrel that was just an average shooter ...after some 10,000 rounds dipped in jb paste it shot the same ... i got bored with it and put on a new barrel. got real shiney, tho. it didn't advance the throat, bullet engraving remained the same, i had chambered it to engrave up to the case. the new barrel was extremely good, so the comparison was valid. ken

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Larry Gibson posted this 06 December 2014

I've been doing considerable high velocity (2500 - 2800 fps so far) testing of cast bullets (#2 alloy and 80/20 lino/lead alloy)in 3 different .308W rifles with 10, 12 and 14” twist barrels over the last 5 years. I have found my 2 rifles (M70 Target and M98 Palma) with the smoothest (mirror smooth) bores give the least fouling....practically none.

LMG

Concealment is not cover.........

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Ed Harris posted this 06 December 2014

500 grit is a far cry from a metallographic microfinish of less than a micron RMS....

73 de KE4SKY In Home Mix We Trust From the Home of Ed's Red in "Almost Heaven" West Virginia

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onondaga posted this 06 December 2014

http://www.castbulletassoc.org/view_user.php?id=207>Ed Harris

"500 grit is a far cry from a metallographic microfinish of less than a micron RMS...."

EXACTLY! Thanks Ed.

Production barrels are generally finished 300-400 grit. My Polishing Method at 500 grit is just slightly finer of a polished finish that will break-in a new barrel without firing a shot, polish the black out of an old military barrel, make the barrel attract and hold Lead from cast bullets less and make cleaning maintenance easier when cleaning after cast or jacketed bullets are fired. It is a one time procedure to give a barrel a slightly finer finish.

Unfortunately, this will never be enough said for people that require looking a gift horse in the butt with a rectal scope. My polishing method is free to look up and try for the members here. I have developed the method and donated it to the forum members here. The stuff needed to do the job is easy to find and obtain and the work required takes elbow grease but can be done in a couple of hours or less.

Gary

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joeb33050 posted this 06 December 2014

(Don't read this, Tom!)

Gary: “Joe B believes a bore can be over polished and cause lead to stick to the bore. He can support that with historical references too. The support he sites only shows me that anybody can overdo anything to the point that it is just wrong and not relevant because it is a deliberate error to prove a point and not constructive at all.”   Ed: “I agree with JoeB that ultra-smooth microfinished bores foul worse because you get increased bore drag in the same manner as dragging a pair of gage blocks against each other or fusing prisms together through their surface adhesion.”   Gary again: “The 500 grit chrome polish I recommend pulled at hand speed on a BoreSnake will not over polish a bore so shiny that lead will stick to it like fusing prisms or gauge blocks. That is an example of abuse like Joe has used in his unproductive argument. “   None of this is what I said, or believe. “”¦cause lead to stick to the bore.” ? Who said that? “”¦gage blocks against each other or fusing prisms”¦” Where was that written? Or said? “”¦ abuse like Joe has used in his unproductive argument.” Abuse? Unproductive?               I don't know when or if polishing a rifle bore will increase accuracy, and neither do Gary or Ed. I don't know when or if polishing a rifle bore will reduce leading or fouling or cleaning time, and neither do Gary or Ed. There's no testing that I know of, with a few barrels, surface finish measured-can you use a profilometer inside a barrel?, shot for group, cleaned and notes taken,  sicked up, shot again, groups measured, cleaned, notes”¦ Anyone done this? Wait a minute- I did a little, maybe 25 years ago. Here's the article from the ASSRA Journal.

onondaga posted this 06 December 2014

http://www.castbulletassoc.org/view_user.php?id=3>joeb33050

Joe, you said over polishing causes lead to stick in bores in your voluminous tirade comment #28 to my original post on bore polishing. You started this. You erroneously equated my polishing method to over polishing that causes lead to stick to bores.

The response of http://www.castbulletassoc.org/view_user.php?id=8045>gpidaho, above,  on this page is supporting proof that my polishing method works as I claim and there have been many others in support also that have contacted me and thanked me.

Gary

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joeb33050 posted this 06 December 2014

Now, as Gary said, I've posted some “sites” about bore polishing. Here's one from Dan Lilja: http://www.riflebarrels.com/articles/barrelmaking/barrelfouling.htm Barrel FoulingBy Dan Lilja I read the excellent article by Fred Barker on fouling and accuracy in his 6.5 caliber 1000-yard type rifle. Per your request I'll do my best to convey my thoughts and observations on rifle barrels and bullet fouling. It has been my experience in shooting a number of rifles and barrels used in 1000- yard rifles, that longer barrels and faster twists tend to foul more. And as Fred pointed out, this could be caused more by the long bullets (and the internal forces acting on them) than the barrel. I found too that some bullets just seem to foul more than others. This is no doubt caused by differences in the gilding metal used to make the jackets. Fred makes some important observations and distinctions between true high-quality custom barrels and production barrels. I liked and agreed with his comment that ” . . . in poor quality, mass-produced barrels, that build up thick, rough fouling and shoot poorly, every shot is a flier.” One of the big differences between these barrels is the internal finish. A rough barrel is going to foul. After looking at the differences between a production barrel and finely finished lapped barrel in our video borescope, a customer made the comparison that the production barrel looked like railroad ties and the lapped barrel like a mirror. Makers of custom hand-lapped barrels spend a lot of time achieving the internal finish that they require. We've experimented with different techniques and products and have settled on what we believe gives us the best finish. We strive to get a smooth uniform finish without losing the geometry of the rifling -- that is, keeping the lands sharp-cornered and crisp. And though it may surprise some, lapping to a finer finish will result in an increase in fouling. A barrel can be too smooth.

And here's an article from the book, (Don't promote it, Tom!) with contributions from Ken M and others, and an article written by Horace Warner before the Maine was sunk.  

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joeb33050 posted this 06 December 2014

And the article about fire lapping, some parts well over 20 years old.

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onondaga posted this 06 December 2014

Joe, I revoke my permission for you to use my polishing method, You just don't get it like you just don't get collet dies and will ruin your rifles worse.

Gary

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joeb33050 posted this 06 December 2014

Now Canuck Bob has you guys riled up, Gary is staunchly defending his bore polishing method, Ed was seen to write “rms", and I still don't know if bore polishing Improves accuracy or Reduces cleaning effort or Can be overdone.

And neither do you. 

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joeb33050 posted this 06 December 2014

onondaga wrote: Joe, I revoke my permission for you to use my polishing method, You just don't get it like you just don't get collet dies and will ruin your rifles worse.

Gary

As I'm sure you know, Gary, all the best machinists will tell you that paper is a very hard substance to cut, and dulls tools quickly. Ken?I've been cleaning my guns with strips of paper towel on an undersize brush for ?3 years now, and seen no reduction in accuracy or cleaning problems.Now that I'm revoked, maybe the paper is polishing my bores and I don't need that bore snake!.(got 223 and 308 Lee Collet Dies, $20 to your door.) (I hope you didn't read this, Mr. A.) 

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onondaga posted this 06 December 2014

Joe, I am just chilling here and back to work on building a Flintlock Kit that I am posting.

Gary

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Ed Harris posted this 06 December 2014

Reminds me of the story about the farmer, the logger and the civil engineer arguing aboyt the best way to remove a 2-ton rock from the middle of a muddy field....

73 de KE4SKY In Home Mix We Trust From the Home of Ed's Red in "Almost Heaven" West Virginia

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Canuck Bob posted this 06 December 2014

Wow, I've decided to fire lap a couple of rifles and then try paper patching in a couple.  If I get Ed's discussion there is no way the results I'm talking about will be as smooth as he relates to cause any drag.  When I worked at Timken Bearing years ago we worked to what us floor staff referred to optical dimensions.  Where the white jackets would measure tooling dimensions by their finish in a sealed room.   I asked this question as an education.  I had read about a slick bore finish causing problems and it seemed counterintuitive.  Anything out of my gunroom would not ever be slick enough to be a problem. 

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Pentz posted this 07 December 2014

I'm surprised that no one has wondered if polishing interferes with the entropy of the bore?.>

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Larry Gibson posted this 07 December 2014

I've fire lapped numerous barrels over the years using the NECO(SP?) kit. I found no improvement in accuracy or lessoning of fouling with good quality barrels. However, with many milsurp and production factory barrels accuracy most often does improve and they foul less with both jacketed and cast bullets.

LMG

Concealment is not cover.........

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gpidaho posted this 07 December 2014

  • 1 Canuck Bob, It might shock and amaze some of the members how little sleep I loose worrying that I may have accidently got the bore too slick. LOL  GP

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Ed Harris posted this 07 December 2014

Gary's 500 grit will produce about 8 microinch RMS in a hard stainlezs barrel of Rc28-32.

The Ti02 liquid suspensions used for final polishing of metallographic specimens are about 2000 and break down further in use.

73 de KE4SKY In Home Mix We Trust From the Home of Ed's Red in "Almost Heaven" West Virginia

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RicinYakima posted this 07 December 2014

Here is another opinion. Gary's process does knock the big machine marks down, but I think the biggest improvement is that the “bore snake” rotates down the barrel at the same rate as the rifling pitch. As those little brass brush ends rotate the woven charged knitted sections, it is orienting the grooves, cuts and flaws to the same pitch as the rifling. So, less fowling and easier cleaning occurs and accuracy is better. My opinion and I'm sticking to it!!

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joeb33050 posted this 07 December 2014

joeb33050 wrote: onondaga wrote: Joe, I revoke my permission for you to use my polishing method, You just don't get it like you just don't get collet dies and will ruin your rifles worse.

Gary

As I'm sure you know, Gary, all the best machinists will tell you that paper is a very hard substance to cut, and dulls tools quickly. Ken?I've been cleaning my guns with strips of paper towel on an undersize brush for ?3 years now, and seen no reduction in accuracy or cleaning problems.Now that I'm revoked, maybe the paper is polishing my bores and I don't need that bore snake!.(got 223 and 308 Lee Collet Dies, $20 to your door.) (I hope you didn't read this, Mr. A.) The 223 lee collets are sold, 308's still ready to go at $20 to your door. Why wait?

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gpidaho posted this 07 December 2014

Midsouth has the Lee collet dies listed @ $19.03 but Joe is offering his shipped to your door. For a one item purchase I call that a good deal. The Lee collet dies are a personal favorite of mine, and I would have sent Joe a check when I first saw his post if I hadn't already had those dies. Now,got to order up the ones I don't have yet. GP

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cheatermk3 posted this 27 January 2015

Joe, As a retired papermaker with 31 years of experience in the industry from Doug Fir logs in the columbia river to chips to Kraft cooking to reams of hiwhite copypaper for Xerox to rolls of bathroom tissue destined for the septic systems of rural homes I can assure you that heavily loaded copy bond is a far cry from soft; it is loaded with TiO2 for brightness and is mostly virgin long fiber. 

Just sayin', there's paper and then there's paper.  Nothin' like a blanket statement to confuse the issue.

Gary's polishing method is not for Match grade or even good quality custom/retail bores it's for military bores mostly in 70+ year old battle rifles.  I have seen some highly regarded mass-market rifles with barrels crafted out of steel that was so full of inclusions it should never have made it out of the mill let along past the gunmaker's QC, but let's face facts stuff happens.  Batch testing is a fact of life.  We must live with it and trust the vendor to stand behind their product.

Some will benefit some will not/don't need it.

My M39 Mosin needed something and benefited from Gary's polishing process in that I can now shoot 40 record rounds (plus 10-20 sighters) in a CBA military match without losing accuracy due to (I have come to believe) powder and lead fouling, as evidenced by the condition of dry patches pushed thru the bore. 

Before the polish they'd have lots of speckles of lead at 20-30 rounds; after, Much less (almost none) speckling.

The Enfield I'm playing with now has a new old stock Johnson Automatics 2-groove barrel which is much smoother than any of my 3 M39s and shows a shiny bore after one dry patch even after 35-40 rounds, and no speckles

You can see from my tech data that I shot pretty much the same load/cases/boolit for three years of competition the only significant difference was the polish as suggested by Onondaga. (I shoot at Clark rifles and Canby using the same outfit in Military scoped and traditional shoots in production class).

For me it's “Thank you, Gary"

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