Barrel break in: Yes or no?

[Busterpayton54]

This makes me face palm. Literally I just did it.

As someone who knows a little thing or two about metallurgy, machining, engineering, physics, and mechanics I can't for the life of me figure out how the tooling marks in a rifle barrel are going to know if they are at round count 20 of a concentrated break in procedure, or the 20th round in 5 years.

This is what happens.. Tooling leaves marks, microscopic jagged marks, burrs and pores.

When a bullet passes over them, frictional forces help lay them in the direction of passing, smoothing them out, and or breaking them off. Heat from friction help as well.
Some jacketing is snagged and deposited on/in these microscopic burrs and pores. Closer to the chamber the more heat helps burn the burrs off.

20 rounds of this in one day is no different than 1 shot per year for 20 years. The end result would be identical.

Copper likes to stick to copper better than it sticks to steel. So once it gets a foothold in these pores and on the burrs, it will build up more and more and more as more bullets pass, and this protective layer of copper is not only protecting the burrs from being beaten down or broken off but building up even more.. Copper fouling.

So yes running some copper solvent through there will keep the buildups to a minimum, so each bullet passing is acting on bare steel and actually leading towards a smoother bore.

But it will the bore know if it's was one day or 20 years? Nope.

Bottom line is cleaning the copper out regularly will speed up the break in/smoothing process via round count, which eventually means more rounds between fouling and better accuracy.. You do not have to do it all at once.

[REMINGTON JIM]

This makes me face palm. Literally I just did it.

As someone who knows a little thing or two about metallurgy, machining, engineering, physics, and mechanics I can't for the life of me figure out how the tooling marks in a rifle barrel are going to know if they are at round count 20 of a concentrated break in procedure, or the 20th round in 5 years.

This is what happens.. Tooling leaves marks, microscopic jagged marks, burrs and pores.

When a bullet passes over them, frictional forces help lay them in direction of passing smoothing them out and laying them into pores, or breaking them off. Heat from friction help as well.
Some jacketing is snagged and deposited on/in these microscopic burrs and pores. Closer to the chamber the more heat helps burn the burrs off.

20 rounds of this in one day is no different than 1 shot per year for 20 years. The end result would be identical.

Copper likes to stick to copper better than it sticks to steel. So once it gets a foothold in these pores and on the burrs, it will build up more and more and more as more bullets pass, and this protective layer of copper is not only protecting the burrs from being beaten down or broken off but building up even more.. Copper fouling.

So yes running some copper solvent through there will keep the buildups to a minimum, so each bullet passing is acting on bare steel and actually leading towards a smoother bore.

But it will the bore know if it's was one day or 20 years? Nope.

Bottom line is cleaning the copper out regularly will speed up the break in/smoothing process via round count, which eventually means more rounds between fouling and better accuracy.. You do not have to do it all at once.

Excellent ! Yupp barrels are not that " Smart" ! Just Don't let the copper build up too much ! jmo RJ

[adriaticum]

This makes me face palm. Literally I just did it.

As someone who knows a little thing or two about metallurgy, machining, engineering, physics, and mechanics I can't for the life of me figure out how the tooling marks in a rifle barrel are going to know if they are at round count 20 of a concentrated break in procedure, or the 20th round in 5 years.

This is what happens.. Tooling leaves marks, microscopic jagged marks, burrs and pores.

When a bullet passes over them, frictional forces help lay them in the direction of passing, smoothing them out, and or breaking them off. Heat from friction help as well.
Some jacketing is snagged and deposited on/in these microscopic burrs and pores. Closer to the chamber the more heat helps burn the burrs off.

20 rounds of this in one day is no different than 1 shot per year for 20 years. The end result would be identical.

Copper likes to stick to copper better than it sticks to steel. So once it gets a foothold in these pores and on the burrs, it will build up more and more and more as more bullets pass, and this protective layer of copper is not only protecting the burrs from being beaten down or broken off but building up even more.. Copper fouling.

So yes running some copper solvent through there will keep the buildups to a minimum, so each bullet passing is acting on bare steel and actually leading towards a smoother bore.

But it will the bore know if it's was one day or 20 years? Nope.

Bottom line is cleaning the copper out regularly will speed up the break in/smoothing process via round count, which eventually means more rounds between fouling and better accuracy.. You do not have to do it all at once.

Lol, I don't think there is an emoticon for facepalm.
The only time round count could make a difference in metal composition is if you shoot a high number of rounds in a short time and make the barrel over heat. Than you could damage the barrel.

[RiverOtter]

Funniest part of it all is, lotsa guys go through the motions of cleaning, thinking they are doing this wonderous job to the inards of their barrel, "Breaking it In", when in fact they are merely removing powder residue and leaving most of the real copper fouling behind. Patches are coming out clean, barrel must be clean, right? Not necessarily. Factory barrels being the worst obviously, due their rougher interiors. Even using products like Sweets, CR-10 and Wipe Out, I'm sure a bore scope would prove that clean is not really clean.

Funnier yet, every barrel I've owned from new has had copper fouling right from the factory. I would expect this is due to legalities, that every production rifle would be proof fired to rule out a catastrophic flaw, which begs the question, "Was it a single shot from a pristine barrel, then greased for shipping, or was it a few shots and highly unlikely that it was scrubbed to bare steel between each?"

My exact "Break In" for a factory tube is this.
1)Pull bolt, insert Tipton bore guide
2)Run a wet patch of Butch's Bore Shine from chamber to muzzle, via Dewey brass bore jag and discard at muzzle
3)Repeat step 2
4)Let barrel sit horizontal for 10-15 minutes and let solvent work its magic
5)Install bronze bore brush, a caliber or two smaller than bore and wrap it in a cotton patch. Add some solvent and run down the bore
6)Repeat step 5
Now that most of the grease, powder residue and some copper is dealt with, I park the solvent.
7)Reinstall jag and run 2 clean patches down the bore to remove leftover solvent
8.)Soak a patch in Isopropyl alcohol and run down the bore, repeating until patches are clean at the muzzle.
9)Run dry patches until the bore is dry
10)Install a nylon bore brush of smaller caliber, wrapped in a patch soaked in Sweets or CR-10 and work it back and forth in the bore several times.
Even though your bore was "CLEAN", you'll notice a weird blue tinge developing on the patch; that's copper. Lotsa guys would have already blasted off round number 2 after step #9 and been rigorously cleaning for shot #3....but hey, they're feeling good about the "break in" and shooting is way more fun than cleaning anyway. Everyone who knows better is currently waiting 10-15 minutes for the copper busters to work their magic, so they can carry on.
11)Reinstall jag and run a couple clean patches through bore
12)Reinstall nylon brush and work the Sweets/CR-10 through the bore to confirm the blue is gone and patches are clean.
13)If your satisfied with step #12, run a couple clean patches via jag, followed by Isopropyl alcohol and lastly more clean dry patches.
14) Wipe your jag clean with IA, as well as your bore guide and chamber, then allow a minute or so for the IA to evaporate.
NOTE: NEVER leave your rifle at this stage, as it is stripped of anything that would help fend rust
15)Install a clean nylon bore brush wrapped in a clean patch and lightly coated in Kroil and work it back and forth in your now "pretty clean" dry bore, followed by removing the guide and carefully doing same to chamber. Allow it to sit for a few minutes for the Kroil to penetrate the pores of the steel.
16)Take a dry patch and work the bore to remove any excess Kroil, as well as the chamber walls so the case can grip during firing.
17)PHEW, can't hardly wait for shot number #2, so I can hurry back to step #1........

Or, just shoot the freaking thing at this point until there is sufficient fouling to group properly, then wait for groups to open up, signalling it is time to clean.

Or, go a step further and skip the Kroil stage in the bore and give it a JB bore paste treatment (Follow instructions on container). Moly coat your bullets, start shooting same and park your cleaning rod outta the way, as you won't need it again for a loooong time.......

[REMINGTON JIM]

Otter had me going for a second Holy Phuck its not a IBS Gun ! then read 17 - OK got me ! LOL RJ

[RiverOtter]

Hey, either you're cleaning or you're just going through the motions..........

[RiverOtter]

Otter had me going for a second Holy Phuck its not a IBS Gun ! then read 17 - OK got me ! LOL RJ

And that is just it, it's a freaking hunting rifle. Whole different animal.

I had the privilege of spending quite a number of hours/days with the Forslund brothers, 2 of the best BR shooters this province has ever seen, so I've seen the lengths people go, to eek out a few thousandths in a 5 shot group. Fact is, 99% of regular shooters/hunters would/could never realize that difference, even if that caliber of gun(Pardon the pun) was placed in their lap; me included. Reason being, even if you master the rifle(the easiest part of the equation) you will get used ugly style by atmospheric conditions, which is what really seperates the men from the boys, if you will.

[brian]

I had the privilege of spending quite a number of hours/days with the Forslund brothers, 2 of the best BR shooters this province has ever seen, so I've seen the lengths people go, to eek out a few thousandths in a 5 shot group.

My wobble zone alone is 3000/1000th of an inch for seated so I naturally pay extremely close attention to any factor that can shave .0002 or .0003 thou off that number.

[hoochie]

....................................

[guntech]

I had the privilege of spending quite a number of hours/days with the Forslund brothers, 2 of the best BR shooters this province has ever seen, so I've seen the lengths people go, to eek out a few thousandths in a 5 shot group.

They were quite the guys... I remember when we hosted a Registered Benchrest Super Shoot back in Alberta at the Namaka Benchrest Range south of Strathmore in the early 70's ... they showed up and cleaned up... they knew what to do when it came to rifles and shooting... I forget which brother won the 40X as first prize...