Do you guys go through the same JB compund hand lapping of your  new bore, and barrel cleaning after every shot or two fired  (for the fist  box of  cartridges) with your Colt Carbine like you do with your other new rifles? I always do this with all my new rifles.

But I was told that this is unecessary with a chrome lined barrel. Frankly, it's a pain in the ass to have to open the receiver, remove the bolt, and clean after each shot. But I'll do it if a Colt is no different then any other rifle that I'd want to maintain and get  the best accuracy from.

imhop, jb has no rerason to be near any new rifle. Used and abussed maybe jb will see the bore.  

I do not belive in barrel brake in. All I think it is doing is shorting the usefull life out of your barrel.

i do not see the need for hand lapping but hey its your money and your rifle.




teh colt barrel is no different from any other its chromelined and will need proper break in!!
so go clean it now and then shoot about 1k through it and clean again.

Chrome lining is so hard, no amount of JB will do anything to it.

Just go and shoot it.

Its not a match bbl. No need for any of that. Just run a patch down it to get any shipping oil out and put some ammo through it (like at least 500rds) go home and clean it. Repeat this process as much as possible.

I have a Bushmaster 4150 steel 24" barrel with chrome lined bore and chamber (basically same config as military except for length, profile, and twist). I never bothered with "breaking it in".

I noticed very good accuracy using even Wolf.

Quoted: Chrome lining is so hard, no amount of JB will do anything to it.

My question was not whether you endorsed and practiced barrel prepping/lapping, as I firmly believe that the process DOES smoothen the bore of a new barrel to minimize copper fouling and enhance accuracy. I just wasn't sure how effective it can be with a Colt Carbine.

I was seeking a validated reason argueing for or against  the pocess of prepping a Colt barrel in particular. The above quote might be a valid point and reason NOT to pursue vigerous prepping.

To be safe, I think I'll do the usual boiling water procedure, and the hand lapping with JB just to make sure the bore is clean and smooth as possible.  But I will cut back on the processs of cleaning after each fired shot at the range.

I suppose the worse thing that can happen is that the Jb compound will have no effect on a hard chrome bore, and I wasted an additional 30 minutes playing with my toys.

Thanks Gents for your input.

Quoted: Quoted: Chrome lining is so hard, no amount of JB will do anything to it. My question was not whether you endorsed and practiced barrel prepping/lapping, as I firmly believe that the process DOES smoothen the bore of a new barrel to minimize copper fouling and enhance accuracy. I just wasn't sure how effective it can be with a Colt Carbine. I was seeking a validated reason argueing for or against  the pocess of prepping a Colt barrel in particular. The above quote might be a valid point and reason NOT to pursue vigerous prepping. To be safe, I think I'll do the usual boiling water procedure, and the hand lapping with JB just to make sure the bore is clean and smooth as possible.  But I will cut back on the processs of cleaning after each fired shot at the range. I suppose the worse thing that can happen is that the Jb compound will have no effect on a hard chrome bore, and I wasted an additional 30 minutes playing with my toys. Thanks Gents for your input.

Go back and re-read my post. I neither endorsed nor refuted barrel break in or "prep" as you call it.

It is a simple fact that chrome lining is hard, very hard. JB bore paste is a mild, very mild abrasive but will do nothing to chrome lining. It will clean stubborn fouling, but it will not smoothe chrome lining or anything close to it.

What do you do with boiling water? That's a new one on me.

Sounds like a lot of work just for a carbine barrel. This ain't no Kreiger you know.

To each his own I guess.

My question was not whether you endorsed and practiced barrel prepping/lapping, as I firmly believe that the process DOES smoothen the bore of a new barrel to minimize copper fouling and enhance accuracy. I just wasn't sure how effective it can be with a Colt Carbine.

 Rebel Rifle

Sorry, I placed that quote in my last post in a confusing manner.  It wan not intended for you, but was intended for some of the other folks who evidently NEVER consider prepping any barrel in ANY rifle!

I was in fact quoting what you had to say here as one really good example of  a valid post on this thread using facts concerning metalurgy. (and thus making the case for why not to bother prepping a Colt chrome barrel.) Opinions by others too, citing that a Colt barrel in a Colt Carbine doesn't exactly fall into benchrest category, are also valid opinions relying on good reasoning behind the rifles design and intended use. (It was never manufactured with the intent to deliver 1/4" MOA groups.)      

As far as the "boiling water process"......that concerns taking the action off of a stock, (or in this case, the upper off of an AR) . After cleaning some of the initial gunk/oil out of the barrel with a patch or two, you wrap a thick towel around the barrel bore, put on rubber gloves, and proceed to pour hot water through the barrel letting it spill out into your sink. You patch and clean ther barrel some more, and repeat the process a few  more times. This helps expand the metal, opening the pores during the process. (Whatever is poured into the trigger group or anywhere else will evaporate from the heat and will not rust) You then proceed with the JB process.
I then clean the rifle after every shot at the range for the first 25 shots or so.

I have performed this process on my factory rifles and have seemed to be able to report better groups out of the box then other guys have reported with the same rifles that they had bought. Is ity just luck that my rifles shot better from the factory?....or does the fussing pay off?


Admittedly though, this is likely overkill in an AR rifle.....especially a carbine with a chromed bore.

Quoted: As far as the "boiling water process"......that concerns taking the action off of a stock, (or in this case, the upper off of an AR) . After cleaning some of the initial gunk/oil out of the barrel with a patch or two, you wrap a thick towel around the barrel bore, put on rubber gloves, and proceed to pour hot water through the barrel letting it spill out into your sink. You patch and clean ther barrel some more, and repeat the process a few  more times. This helps expand the metal, opening the pores during the process. (Whatever is poured into the trigger group or anywhere else will evaporate from the heat and will not rust) You then proceed with the JB process. I then clean the rifle after every shot at the range for the first 25 shots or so. I have performed this process on my factory rifles and have seemed to be able to report better groups out of the box then other guys have reported with the same rifles that they had bought. Is ity just luck that my rifles shot better from the factory?....or does the fussing pay off? Admittedly though, this is likely overkill in an AR rifle.....especially a carbine with a chromed bore.

Don't take this wrong, it is not meant as a flame.

Where did you hear of this? I am curious. I have read and talked to many different barrel makers on their break in process or lack thereof and their opinion on it as well and yours is the very first time I have heard of using hot water in this process.

Some barrel makers say break in is essential and some say it does nothing but take barrel life away with every shot. I have broken some in and have not on others and to honestly say I have seen a difference, I cannot. I have yet to get a bum barrel but some do. This includes factory and premium barrels. To say I could have gotten *better* accuracy out of a barrel if I had broken it in, I do not know and quite frankly no one else does either, it cannot be quantified since the break in did not occur. How do you know what you *could* have gotten?

All that being said, I have talked to some barrel makers and they do advocate proper break in mainly to remove tool marks from chambering and rifling. These tool marks are in just about all barrels (non chrome lined) and if not smoothed out you will see above normal fouling such as copper and the like. In this respect break in does help.

I have also read from Gale McMillin (McMillin Bros.) that he said all break in was essentially nonsense. Some say it works and some say it doesn't. I think in the end, use what you want it is your barrel. Even after all of my experiences I am still somewhat neutral on all of this. At times I think it does work and others I don't think it does much if anything at all.

I think your last statement (highlighted in red) is VERY true.


Good luck with whatever you do.

A few years ago there was an article in American Rifleman on the Water method.  JB can harm chrome just as well as any other barrel. Use it the wrong way it can and will do damage.

Just to be safe I would flush out the gas system after you use JB. You do not need any jb getting blown into the BC group causing premature wear of the parts.

Rebel Rifle,

I learned of the water prepping method from a Rifle Shooter  Magazine article from 7 years ago that was authored by Jim Shults. He claims to have won a number of regional, state and national awards, as well as "Distinguished Rifleman".  I don't know if Distinguished Rifleman simply means he's one of those silly asses that dresses up in an 1890's reenactment uniform like from out of a John Wayne movie. I am not a competitor of any sought to be familiar with the various tournaments. But still winning a bunch of competion contests, I'm sure this guy knows a lot more on the subject of barrel prep then I do.

The '' hot water" method I mentioned is actually not hot water, but instead is really a pot of boiling water that you put to use. (about a gallon) After cleaning the initial factory gunk out of the new barrel with standard Hoppe's style cleaner, you then squirt dish soap int the barrel and pour the water in. You can stand the barrel muzzle on a rag in ther sinkand let the boiling hot water stand in the barrel, with the soap in there for a few moments, and then let it run out. You repeat the process, in between swabbing the barrel with a clean patch.  You then JB the bore. The patches keep coming back blacK and then gray. They never come back 100% white. So Obviously there's some cleaning and polishing going on during the process as intended. This is what I do with my bolt action rifles that I desire MOA accuracy out of.....

BUT AGAIN, I DON'T THINK THIS PROCEDURE IS AS IMPORTANT, NECESSARY or EFFECTIVE WITH A COLT CARBINE.

GREG,

That's a good point you made about the JB getting into the BC group. Though there's a natural amount of carbon residue that occures naturally in the barrel from firing the ammo anyway, I'll be sure to rinse out the barrel one more time with hot water after the JB compound process.

Thanks for the clarification on the boiling water. That is the first I have heard of using it other than cleaning up after using corrosive ammo. Sounds like a lot of trouble to me, but if it works for some, have at it.

Distinguished Rifleman means that he was/is a highpower competitor. Can't say as I have heard of him, he may have become distinguished long ago.


Thanks for the info.

VaniB, here are specific instructions directly from Bushmaster's website.  Hopefully this cuts to the heart of the matter.  Not saying anyone is wrong here or trying to start a flame war, this is just what this manufacturer says is best for their chrome lined barrels.

"Cleaning the AR15 - with its chrome lined barrel - is a little different than cleaning a regular sporting rifle. The chrome lining will take longer to break in - usually 100 - 200 rounds, and once properly broken in, will really not require much scrubbing until many thousand rounds later when your target groupings start to suffer. Chrome barrels don't get fouled nearly as quickly as steel barrels, and they won't rust or pit either. Here's the basic cleaning process - after a shooting session, clean the bore and chamber with a nitro solvent (Hoppe's or equivalent) and run patches through until all solvent is removed. Caution - any solvents that can affect nickel may damage the finish of the receiver unless removed. A Nickel Acetate sealant is applied as one of the receiver's last finishing steps, and some solvents will attack that finish. The use of a chamber rod guide (available in our catalog) will limit your cleanup. Once the rifle is clean and dry, apply a light oil with Teflon but don't over-do it. We sell the Tetra brand, others are Break-Free and Rem-Oil. The manual that comes with your rifle will show you how and where to oil. After many (thousands) of rounds, if the rifle's accuracy starts to suffer, scrubbing the bore down with a good copper solvent, plenty of elbow grease, and patience, will produce a barrel that shoots as good as new."

Here's the link:    http://www.bushmaster.com/faqnew/content_by_cat.asp?contentid=182&catid=101

Hope this doesn't violate any forum rules for copright infringement or anything.

Bobafett,

Thanks, this is more usefull info.  I had long forgot about this thread, when I happened upon your post. It just solidifies my belief that using the boiling water method along with Jb's at the start can't hurt, but is probably over kill with a chrome lined barrel.

I certainly will not fuss with cleaniong after every other shot during my initial range visit as I normally do with my other rifles.