Tubb's Bore Polishing Process

[Rex Rugged]

Has anybody got experience with David Tubb's bore polishing kit? It contains a a series of bullets impregnated with a polishing compound in sequential steps for new barrels. The idea is to load these bullets in low velocity amounts and fire so many rounds of one compound clean the barrel and proceed to the next finer polishing compound. The idea is to remove any microscopic roughness left in the barrel from the manufacturing process.

 

[JohnKSa]

The process is sometimes called Fire-Lapping. Some people claim you can get a roughly similar effect by doing a barrel "break-in" process that involves repeating the steps of firing and thorough cleaning when the barrel is new.

Or, you can find an expert to lap the bore by hand or maybe even try to do it yourself.

 

[FrankenMauser]

Fire-lapping can really wake up (or 'calm down' if you prefer) some bores.
Or, it can cause premature wear and make a bad rifle worse.

Is it worth the gamble?

 

[stagpanther]

Controversial stuff--I've heard very strong opinions on both sides of the issue--some saying all you're doing is prematurely wearing your bore--while other say it's great at smoothing out the rough spots and improves consistency. I've actually used the tubbs stuff on quite a few different calibers--but never on a new barrel or one that I've had no problems with. I have used them on barrels that started to show signs of problem throat erosion and/or a barrel that came with obvious bore damage that I couldn't return. Once in a while the Tubbs bullets even print a group that's beaten my best developed loads!

I wish we had the internet version of the bat-signal that we could turn on to get Unclenick to drop by and comment, he had some good pointers a while ago on using Tubb's lapping bullets.

 

[Shadow9mm]

I did it once. Followed the directions to a T. All i did was chew up the start of the rifling. Personally i will NEVER, use it again, and i recommend against using it.

Let me ask this. What makes you think your barrel NEEDS the tubbs system? And exactly what are you hoping to accomplish or achieve by shooting abrasives down your barrel?

Many high end barrels are hand lapped with a lead lap poured into the barrel and coated with polish. None that i know of use the tubbs system.

In some circumstances having a highly polished bore can cause increased copper fouling based on my research and personal experience.

I would offer 2 suggestions

Break in the barrel. Shoot 2 or 3 rounds, clean the barrel, especially copper, and repeat. By keeping the microscopic imperfections clean the plain bullets will smooth them out. Thats the idea behind a barrel break in. I don't buy it, but thats what they say.

Option 2 is the jb, vfg bore pellet system and kroil as a lubricant from brownells. They have jb bore pase which is an abrasive meant to help clean stubborn fouling.they also offer jb bore bright, which is supposed to polish the battel and make future cleaning easier. Remember, the black you will see is metal that has been removed, not fouling, dont go crazy. Heres a video on the process. https://youtu.be/_pFNccaNVOA?feature=shared

 

[HiBC]

I value my time. Years ago,a I was building a few rifles, I figured out that "bargain barrels" were a crap shoot and generally not a bargain.

The threading an chambering ,etc is the same for a Kreiger as it is for an Obscure Barrel Co $79 on sale today special barrel.

How much does a bar of proper grade barrel steel cost? How much does it cost to gun drill the blank? What I'm getting at is am I even tempted to buy an "under $130 pre-threaded short or long chambered barrel?

There ARE different budgets and priorities, but what I consider very good,worthy barrels would come from Criterion, Lothar Walther,Douglas,Shilen,
White Oak, Wilson, etc. All good barrels. Good barrel makers.

I have no fantasy that any home remedy I do on those barrels will be an improvement.

But suppose we do end up with a "bargain" barrel that fouls badly or is inaccurate. Bore finish or tight /loose spots .

If its a garbage barrel for a utility rifle I might figure I have nothing to lose and fire lap it.

When Ross Seifred wrote a review in the Ruger Lipsey special ,he suspected the bore was tight where the barrel shank screwed into the frame. The bore was swaging the bullets undersize for the remaining bore. He fire lapped the constriction out. Accuracy improved.

There are SOME applications where a specific problem is identified that fire lapping MIGHT remedy. Maybe.

Grit size, like 240 grit or 600 grit,those (as I understand it) are screen mesh sizes. Roughly,200 grit would be .005 rocks. 500 grit would be .002 rocks,
1000 grit would be .001 rocks. Thats over simplified,but it will serve to illustrate my point, Assume the "lapping bullet" is sized .300 Assume 50% of the grit gets embedded in the lapping bullet.
What happens if you lap with coarse to fine grit? (Note: This applies to lapping a 1911 slide to frame,also)

The effective cutting diameter of the 200 grit bullet would be .305 The 500 grit bullet would be .302 and the 1000 grit bullet would be .301,

If the coarse grit cuts .305, will the fine grit at .301 even cut?? Maybe Mr Tubbs has that worked out, But I was rolling my own diamond compound on the bullets. I chose 1 grit,green # 9 diamond and its the only size I used.

The barrel I lapped looked like a washboard road with stretches of smeared cheese, It actually ended up shooting very well.

I say,save it for when you have nothing to lose. Then,have fun.

One more thing . Whether fired through the barrel or cast in the barrel, a lap has form and size. No rag or felt or wad or tampon shoved through the bore with ay grit past from flitz to simichrome to JB ,etc has form or size. Shiny is NOT the point. This stuff just washes out what your barrel maker was trying to achieve. It might be OK for removing fouling,maybe, but you can't lap a barrel with a rag,or a pellet.

While I'm here,some big name hot shot shooter was recommending CLR for bore cleaning. I advised "Thats just wrong"
But the Lemmings followed "Big name hot shot shooter" because he is,after all,Messiah.
So the Lemmings swabbed their bores with CLR.

Later,I recently saw his Youtube post, Big Name Hot Shot Shooter said " I was wrong! That was a BAD IDEA! Don't use CLR!!"

Great. Will he buy the Lemmings new barrels? Use your heads,folks! CLR? Thats nasty!!

 

[Shadow9mm]

Clr works fine, provided you have a stainless barrel. It eats bluing for breakfast.

 

[stagpanther]

While I'm here,some big name hot shot shooter was recommending CLR for bore cleaning. I advised "Thats just wrong"
But the Lemmings followed "Big name hot shot shooter" because he is,after all,Messiah.
So the Lemmings swabbed their bores with CLR.

Later,I recently saw his Youtube post, Big Name Hot Shot Shooter said " I was wrong! That was a BAD IDEA! Don't use CLR!!"

Great. Will he buy the Lemmings new barrels? Use your heads,folks! CLR? Thats nasty!!

I was one of them that followed big shot's advice (though I just tried it out of curiosity on one barrel). I agree, CLR is not something that should be used with firearms in the same sentence or otherwise. (wonder if big shot got a fat commission check from barrel makers)

 

[Bill DeShivs]

Using lead and an abrasive to lap a barrel will work- on the first stroke or two. Lead is pretty soft and deforms almost as easily as a tight patch. Think about it.

 

[Rex Rugged]

Thanks for the input guys. I will store these bullets forever probably now. That is exactly why I signed up here, to get info from experienced shooters. I firmly believe what makes wisdom is intelligence enhanced by experience!

 

[HiBC]

Using lead and an abrasive to lap a barrel will work- on the first stroke or two. Lead is pretty soft and deforms almost as easily as a tight patch. Think about it.
__________________

I have thought about it. I have done it,too. So did Harry Pope (but he knew what he was doing)
In the 1920's or 1930's, a Gunsmith named Clyde Baker wrote a gunsmithing book. I think the title was "The Modern Gunsmith" ,not to be confused with Dunlap's version.
He describes the process.
The lap is cast in the bore around a tapered brass screw. Turning the screw tightens the lap.
I appreciate that you are a skilled craftsman.
I was sent to a Mold and Die finishing house in Chicago by my employer to understudy a Master.
When I arrived,he was working on coining dies for a Mint.
We used laps a lot.
Polishing plastic injection molds requires maintaining form. And hitting dimension. Clear plastic parts have to look like glass,no distortion.
With respect to you,I know something about polishing with laps,and brushes,and hard and soft felt. Many of my laps were made of cast iron on a surface grinder.
The stones I used most of the time were puddle stones. A lot like Japanese Water stones.I drove them with my DME Jiffy Profiler. The setup was a lot like a Custodians dust mop, The stone was stroked but floated flat in the surface.
These stones are designed to break down quickly,and assume the form of the workpiece.

Properly used,laps preserve form. They don't wash out detail,or create ripples ,or round corners.

FWIW, the cast 30-30 bullets I used to successfully fire lap a rough 30-06 barrel only made one pass through the barrel.
I only used one grit of abrasive, Gesswein #9 green diamond polishing compound,smeared thin on glass, I rolled the bullets in it.

 

[Rex Rugged]

Nothing like a serious, experienced craftsman HiBC. I appreciate your knowledge sir and thank yopu for sharing.

 

[4V50 Gary]

Years ago barrel maker Bill McMillan was asked about barrel lapping. His response was just to shoot the gun.

 

[HiBC]

Years ago barrel maker Bill McMillan was asked about barrel lapping. His response was just to shoot the gun

Gary,I agree! I don't put my time into cheap barrels anymore!

For all the effort and expense that goes into building a rifle,why cut corners trying to save $ on the barrel?

While I'm sure Mr McMillan had people skilled at lapping barrels, I have no fantasy I can improve a McMillan,or a Krieger, or any other quality custom barrel with any of my amateur efforts.
The times I tried firelapping or other experiments I was working with a known stinker barrel.
I had nothing to lose. It was as much an experiment with the process as it was "I'm going to "fix" this barrel" I was figuring I'd probably remove it and use it for a cheater bar or something.

My advice is "Buy a good barrel" and then "Don't do anything to it. You paid the barrelmaker for all that"