What makes a barrel quit shooting

[JRB]

Hovis,
Thank you for your detailed input,
I can see your points and appreciate them, was just seeing if you or others, wanted to know more about barrels and what made them work
Does your barrel have increased fouling as its aged
I can only assume that the sudden jump in AOL, was the lands were quickly eroding, as the taper was moving up the bore, as wear compounded.
What's your thoughts on what makes this a freak barrel
The internal characteristics must have changed dramatically over its life, but it still performs
Jim

 

[HovisKM]

JRB,

Fouling has never really seemed to get worse as the barreled aged and yes, the throat is eroding at a very rapid rate now. Up to the 4000 rd mark, it only moved about .001 per 400rds, so the pace has really picked up now.

I spoke to a barrel maker this weekend and a couple of others who have seen barrels like this "back in the day". No one had an answer other than they "just exist", same answer you'll get about a hummer barrel.

My opinion is three fold...one, great steel....two, an excellant button that worked perfectly in this type of steel....three, something unmeasureable.

One thing is for sure...when shilen had their prized 6mm button break...it wasn't long before they fell off the top ten equipment lists. But, when shilen gave away barrels to winners, it was told to me by several that people listed their barrels even if they wasn't using them.

Hovis

 

[Pete Wass]

Choke

One of the comments about muzzle end damage stuck a cord.
If a dry patch is first run down my 30BR barrel after a shoot, the normal expected resistance is felt until the last 2 inches where the resistance rises very noticeably.
It feels almost like the bore narrows. When cleaning is complete, the resistance is constant the whole way.
I couldn't guess if this is bore damage (accuracy killer) in the making. Just something puzzling.

Many or mebby even most rifle barrels are lapped with a "Choke" in the area behind the muzzle. I recently sold a rifle that had a 30Cal Kostyshn barrel on it that has a very tight choke at the muzzle end. Shoots great though but there is a very noticeable tightness when cleaning. When one looks at that area with a borescope the barrel looks pristine, when clean. I have noticed that when barrels start to Copper Foul a lot they start to shoot less well. I know some lads who have taken discarded barrels and made tem shoot well again by lapping them. They do say those barrels don't last long though.