Barrel break-in&cleaning????????

[yotebuster]

I just purchased new Model 7 223 for my wife and have read 20 different opinions on barrel break-in from it's a wasted time to 100's of different procedures. In my Kreiger barrel I just followed Krieger's break-in, but on a factory what have you had the best luck with and what cleaning agents used? I've been using Montana Xtreme and Bore Tech on Kreiger. Thank You for your time and input.

 

[tightneck]

IMO custom barrels don't need to be broken in. Factory barrels are more likely to benefit from some kind of breakin procedure. That being said, I think their are lots of factory barrels out there that cannot be helped, no matter what you do. If it makes you feel better, follow the same procedure you did for your Krieger, but don't be suprized if the barrel still fouls badly. I find that custom barrels simply don't copper up much unless they are chambered for really overbore cartridges, no matter if I use a breakin procedure or just shoot the first 25-30 rounds and clean it.

 

[chino1969]

yotebuster,
I agree with what Tighneck just said. If you look in the bore of some factory bores with a borescope you will see that no amount of break in can help; just load and shoot! The gun may still shoot well enough for your purposes but don't waste your time breaking it in. Custom barrels are a different story with different opinions. I shoot a couple of rounds, clean and shoot a couple more rounds and examine the color of the patches. If the patches are a light blue, I'll increase the number of rounds fired and then clean. The color of the patches dictate my break-in regimen and many times I'm shooting ten round groups after about thirty rounds. When I hit fifty rounds, I usually start cleaning after twenty rounds. On custom barrels, I never go over twenty or thirty rounds max. before cleaning.
Chino69

 

[Spotcheck_Billy]

I just finished breaking in a Bartlein 5R barrel. I used Montana X-Treme bore cleaner followed up by their 50 BMC Copper Cutter doing the shoot one and clean routine. By the third shot copper, as evidenced by the amount of blue residue coming out on the patches, was definitely getting less and less on each shot. By the ninth shot there was very little, if any, copper evident after a single shot. That's when I stopped the shoot one and clean regimen and started cleaning only after twenty rounds or more went down the bore. Even then there is very little blue coming out on the patches. I've switched to Wipe-Out on this barrel, as I normally do once I feel that a barrel is broken in.

I've had other high-end barrels that took almost forty shots to break in.

All barrels are different. I've seen factory barrels that never seem to stop coppering. If they group well I just shoot the heck out of them. If they don't, I'll either get rid of the rifle or rebarrel.

 

[mikecr]

Break in?
I don't understand how a smooth copper bullet can effect much change in a barrel.
Seems to me that a change in copper fouling rate during breakin would be due to carbon fouling filling in voids previously filling with copper. Eventually cleaning will not remove ALL carbon.. So you get to go more rounds before copper fouling sets.
Good or bad, I think thats what happens. I think thats why you have to get a barrel fouled to shoot consistant.

Actual break in must have a purpose.. To remove, or change the shape of unwanted metal. To match metal parts in contact.
The only thing I can think of here to 'match' is the bullet ogive to the leade. Remnants from chambering, or imperfections from rifling might be smoothed out. Anything about the bore which isn't straight,least resistance) might be worn through shooting, without loss of accuracy,but I doubt it).
The only way to make these things happen..To actually breakin a barrel..Would be through fire lapping.
Atleast, that's the way it seems to me. So I use Tubbs TMS for break in. 10 shots, finest grit.

 

[jb1000br]

You are not breaking in the barrel, you are breaking in the throat...I have done hte last several and documented it...there is a lessening of copper fouling as the process goes on.

2 broughtons, a kreiger, a pac-nor, and working on a rock right now.

1 shot till there is no blue from copper. the 2 shots at a time till there is no blue after 2. I quit there, and go on to load development. I have not needed more than 20rds to do this.

YMMV,
JB

 

[mattdienes]

I used to do the "1 shot,clean" deal. Well I don't do it anymore. I'll take a new barrel and work on the throat are with JB or isso for a good while,clean it up,run a patch of Lock-ease down the tube and shoot a 5 shot group with a relative mild load,take it back in and clean,making sure its real clean,,I use 50 BMG for copper,Butches for carbon),lube it again and shoot a 5 shot group,clean again,the go to load develope.

This has worked for my last 4 barrels-Kreigers& Barleins everytime and the barrels still clean easy.

As JB said you just have to smooth out the throat area,the barrel maker did the hard part.

Factory rifles are a different story,some "break in" some never do,but trying to polish out the throat on them will help a great deal along with a good cleaning while not shooting a high number of shots between cleanings.

 

[tenring]

JB - If all copper accumulates in the throat, why can it be ob served right at the muzzle on some factory barrels? There are some theories that a little copper aids accuracy.

And, the carbon ring at the throat is also important, but difficult to clean. How do you attack that area?

 

[mattdienes]

I have talked with some gunsmiths about that and is was conclude by all of them that the copper at the muzzle is a result of jacket material being stripped off and vaporizing with the gases only to become a solid material again as it cools down at the muzzle,most likely from a rough throat,factory) or excessive wear in that area.
It seems to me when i get alot of copper coming from a barrel if I spend some time in the throat and just after a couple of inches it will clean up faster.
I never paid alot of attn to streaks of copper on the muzzle as I believe you will always have some to an extent on factory barrels.

 

[edpmedic]

Yote..I have found that in a factory barrel that the Tubb Systm really helped my 308 barrel including a Mike Rock 5R. I even looked at it before and after with a Bore scope and it was really a major change at the Leade and through the barrel.

It also do close my groups up at 100 and 200 yds. Then at Williamsport I saw a slight difference. So I figure since I am a crappy shooter it would have been tighter if someone good shot the rifle.

I also have found at least on Factory Barrels that really cleaning them out is not a good idea. I think if you take all the copper out of the barrel your cold bore shot is always off. Till you get all those little ruts filled in. Getting the carbon out is the most important thing for barrel life.

 

[chino1969]

JB - If all copper accumulates in the throat, why can it be ob served right at the muzzle on some factory barrels? There are some theories that a little copper aids accuracy.

And, the carbon ring at the throat is also important, but difficult to clean. How do you attack that area?

tenring,
I can tell you what I have observed using a borescope during the break in process on a new custom match grade barrel. Looking down the bore in the freebore area, before the rifling, there are tiny circumferential scratches or marks left by the reamer. The theory is that the break in process serves to remove these circumferential scratches which act like file teeth the bullet jacket makes contact with, as the bullet is travelling perpendicular to these marks. Combine this mechanical 'rasping' effect with the pressure and plasma effect of the combustion process causes the copper to plate out in the throat area in these little scratches. Whether the break in process is necessary in a match grade barrel is, in my opinion, a matter of personal preference. These scratches are going to be eventually removed as part of the shooting process, whether you shoot one and clean or shoot twenty and clean. A very thin copper wash is going to fill in the microscopic voids in the barrel steel which is going to smooth the interior of the bore. This is what you are doing when you fire one or two 'fouling' shots from a clean bore.

The carbon ring that you hear about can build up over time in the throat area and can become hard like glass if allowed to. Visualize the interior of a rifle chamber for a moment. There is the chamber area, the neck area, the freebore area, and the rifling. The throat is actually the transition from the freebore area to the rifling and usually 1 1/2 degrees; a ramp if you will for the bullet ogive to mate with. The area where the neck ends and the freebore begins is a space where the larger diameter of the neck ends and the smaller diameter of the freebore begins. Think of it as a shelf where carbon can accumulate. In time, this area will build up with carbon and extend into the throat area where it can interfere with the bullet and also change the volumetric dimensions of the neck/freebore area. This build up of carbon needs to be removed periodically. I use Mercury Quicksilver carbon cutter and JB bore compound to go after the carbon. I use a borescope to monitor this buildup and go after it when it begins to accumulate. I don't do this everytime I clean, but after approx. every fifty or sixty rounds; again the borescope dictates the cleaning process. I hope this helps.
Chino69

 

[jb1000br]

Tenring...sorry I missed that Q...my response would mirror mattdienes post above.

BREAK IN TIDBIT:

Just finished breaking in a Rock Creek 6mm barrel.

1-shot then clean for 9 rounds,using near max loads with 105 A-Max bullets)...copper that was evident after each shot started lessening after 6-7rds...I had a feeling #9 was the break-in point...shots #10 and 11 were then fired back to back without cleaning between. Upon cleaning after #10 and 11, there was NO EVIDENCE OF COPPER. Bam! Barrel is "broke in"

obviously something was happening to lessen copper fouling...so I think there is some merit to the process.

Does it occur naturally without "proper" break-in, probably.

FWIW, I have also found the break in point similarly with broughtons, kreigers and a pac-nor...all wer similarly between 7 and 12 rounds fired.

JB