Bore Treatment and Cleaning.

[Badger Arms]

Let's talk about bores. I'd like to hear other's ideas about factors that have an effect on bore erosion. This is a very broad subject and some are VERY anal retentative about the whole bore thing.

We all know what is good and bad for a bore. Corrosive ammo is bad, cleaning is good. (one may argue with me about either of these but that is another subject) Beyond this, how do you guys and girls treat their bores?

I'll start. I lap the bore from the breech when I get a gun (bolt actions only). I judiciously use 800 grit lapping compund and follow this up with some polish using patches and jags. I then thoroughly clean out all the compound, and apply some Tetra-Gun oil to it. I used to use EEZOX.

Following this treatment, I clean the bore after each range session by altrenating between wet patch, bore brush, dry patch, wet patch. The final patch is wet for storage or dry for near-term usage. The main reason I lap is for ease of cleaning. I frankly don't care about velocity or accuracy as these are almost always satisfactory.

As far as leading or metal fouling... I've never really had that much of a problem with either. Leading on my revolvers has never concerned me. I guess others just shoot softer bullets than I do. Copper fouling has NEVER bothered me. I know I get a little and it looks funny, but it's never changed the accuracy, point of impact, or anything in how my guns act so why worry?

Any thoughts? Moly-Coating? Fire Lapping? Break-in Periods?

 

[bullseye]

I don't own any match grade barrels, so I don't get obsessive about the various approaches to breakins, lapping, etc. When I get a new gun, I give it a complete cleaning to get the factory crud out and lube it up. Then I go out and shoot it, give it a good cleaning, oil swab the bore, lube, oil and wipe down the gun and put it away for next time.

 

[Southla1]

Badger Arms, your theory makes sense to me. I guess we both shoot the same kind of cast bullets because I have NEVER had a leading problem with any of my personally cast bullets, and as far as copper goes a few of the copper solvent patches take care of that in a jiffy. Half the time I do not even use a brush, I just pass a wet patch in the bore let it sit for a few minutes and pass a dry one and do this over and over till they are not bluish-green. Oil it and its finished! Velocity and overbore cases seem to be the biggest cause of throat erosion. There is also some schools of thought that double based powder contributes to bore erosion more than single based powders, and that single based ball powders are easier on a bore than extruded pwoders. I guess this is true because lots of smarter shooters than I am have deduced this! Now, on to corrosive primers ........ yes they can ruin a good barrel in short order ........ IF improper cleaning methods are used. If proper methods are used, corrosive primed ammo is no harder on a bore than non-corrosive proimed ammo. Look at it this way 50 years ago ALL military ammo (except the M1 Carbine) used corossive primers, but there was not a great deal of concern about it because back then all shooters knew how to clean after firing it. Even GI bore cleaner back then was designed to remove the chloride residues of corossive primers.

 

[Badger Arms]

Wheel weights and beezwax are all I ever did. I don't cast bullets anymore for fear of the Environmentalists (and my children).

It's insightful that even though they KNEW how to clean their guns, GI's often couldn't or didn't. The result is that their guns often showed undue erosion because of it. This was acceptable. The M-1 Garand was not intended to last forever. Indeed, Military Rifles have a top limit of about 20 years in service (John Browning designs being the exception). While Non-Corrosive ammo was partly the reason why the Carbine bores fared better, it must be remembered that velocity and pressure were also much lower.

Is it grain shape that causes the erosion with extruded powders? Never gave that much thought? Is there something different about the burning characteristics of ball and extruded powders? Single vs. Double based?

I don't buy into the 'if everybody thinks it' school of thought either. If I can't visualize it, I doubt it. I think Dick Casull came up with a cartridge that burned the powder in the case instead of pushing it down the bore to burn as most cases do. There is a flash tube in his case that starts burning the powder behind the bullet avoiding the stream of sharp powder that is shoved down the bore in current designs.

 

[Southla1]

"Is it grain shape that causes the erosion with extruded powders? Never gave that much thought? Is there something different about the burning characteristics of ball and extruded powders? Single vs. Double based?"


NOW THATS A GOOD QUESTION!
Everything that I have read from Nonte on, says the same thing. I figure the man that can shoot enough to notice the difference is a LUCKY man. I do have one thought on the matter, and that is that the shape and size of the powder grains may erode (abrade) the bore as they are "blown" out of the case on ignition. Some do get blown into the barrel and burn there. Possibly the balls being round have less friction and less sharp edges to do that abrading? I don't know its just a thought. As to double based pwoders possibly the nitro added burns hotter? Again I don't know.

I use a mix of linotype and wheel weights with a regular alox lube. I drive some 30 caliber 170 bullets right at 2300 fps (gas checked) in my 06 with no leading. 1600 in my 44 Mag (no gas check) with the same result.

Corrosive primers do not erode a barrel throat they just flat out rust the whole damn barrel and real QUICK to. Espically in this humid area down here! Something else I always noticed was that GI's that were more caring and intelligent (not always but most of the time) were the ones that did everything right, including weapons cleaning. When I was instructing at the Air Police school weapons training I can promise it was woe to the trooper that I caught not cleaning one properly .