quote:

Originally posted by Poleax:
Just a question but who here really follows a barrel break in routine? Not trying to start something but just wanted to know.

quote:

Originally posted by butchlambert:
What do you tell a customer if the barrel looks great and it still seems to have a problem? Do you ask him what the 'ell kind of question is that or try to find a reason?
Butch

quote:

Originally posted by Rick 0311:
Here’s what Krieger has to say about it.

Q: What causes copper fouling in a barrel?
A: There are several factors: · The finish of the bore. · The roughness of the throat after chambering. Fouling can start back at the throat. (Please see our "Barrel Break-In and Cleaning" Instructions.) · Quality of the bullets. I.e. match bullets Vs military style ammo (fmj) or lower grade factory ammo. Good quality hunting bullets that have pure copper jackets to control expansion will tend to foul more. · Pressure. Our experience and some of the bullet manufactures' is that the higher the pressure, the more the bullets tend to foul the barrel.
When your barrel is chambered, by necessity there are reamer marks left in the throat that are across the lands, i.e. across the direction of the bullet travel. In a new barrel they are very distinct; much like the teeth on a very fine file. When the bullet is forced into the throat, copper dust is released into the gas which at this temperature and pressure is actually a plasma. The copper dust is vaporized in this gas and is carried down the barrel. As the gas expands and cools, the copper comes out of suspension and is deposited in the bore. This makes it appear as if the source of the fouling is the bore when it is actually for the most part the new throat. If this copper is allowed to stay in the bore, and subsequent bullets and deposits are fired over it; copper which adheres well to itself, will build up quickly and may be difficult to remove later. So when we break in a barrel, our goal is to get the throat polished without allowing copper to build up in the bore. This is the reasoning for the "fire-one-shot-and-clean" procedure.

quote:

Originally posted by malm:

quote:

Originally posted by butchlambert:
What do you tell a customer if the barrel looks great and it still seems to have a problem? Do you ask him what the 'ell kind of question is that or try to find a reason?
Butch

No, I only use those terms here. What I tell customers where there isn't anything apparent, is that there are a gazillion reasons barrels foul.

I have a customer who has a little .308 with a very smooth hand lapped Shilen barrel, that only seems to foul with one particular bullet, and only then when that bullet is seated into the lands. Same bullet doesn't foul when backed off the lands, yet his best accuracy is when that bullet is jamed into the lands. He prefers the bug hole accuracy that this rifle delivers, and so he is comfortable with it even though he knows he's in for a little extra cleaning.

It's frustrating as hell at time to try to explain things when there is no obvious cause and so we are stuck with phrases like "I don't know". Most customers appreciate the candor and honesty when they see you aren't trying to blow smoke up their ass. Not everything is so easily explained and so it does no good to make something up. Most of the time you will find the cause, or, a contibutor to the fouling problem when scoping the barrel, or, while examining a recovered bullet, but there are going to be times when you just flat can't explain it. Those are the times I was referring to.