Like always, this is aimed more at beginning to intermediate chamber cutters. I don't have anything of value for an experienced guy.
It was that brand of carbon barrel I REALLY dislike. They are always dirty inside, very crooked, horribly wallowed out at the breech, and button rifled. I think button rifling is a bad idea on a liner for a carbon barrel.
It was hard to dial in as these barrels usually are. It's like the rifling isn't a consistent height. These barrels always need to be scrubbed, which helps some, and I need to cut the rifling out of the breech with the chamber reamer (or a throater) just to have an even surface for dialing near the breech.
I still dial in these barrels just ahead of the throat and about a 1/2" in front the breech. I suppose drill and prebore would work as well, but they would be a terrible choice for end dialers--they are that crooked. They can also give a Grizzly rod a very hard time.
The reamer looked okay, but when I bore scoped after just cutting a little ways, the shoulder looked rough. This was a brand new JGS reamer in .223 Wylde. So I pulled the reamer and went over the flutes at the shoulder with a diamond file--25 micron I think. On subsequent inspections the shoulder looked fine.
However, the big deal was how awful the ends of the rifling looked. Now the rifling in these barrels is always funny shaped. When crossing a land, the Interapid needle jumps up and drops a little, stays relatively even, then jumps up again before falling into the groove. It's like there are ridges on each edge of the lands, with the trailing ridge seeming to be a little bigger. So the end of the rifling often cuts funny.
Well this time, along with the funny rifling ends, the throat wasn't cutting evenly. I thought I should have been past the wallowed out area of the breech, but I pulled the reamer anyway and dialed the barrel in some more. I did get it a little better. That solved the uneven throat cutting, though the rifling still looked funny.
Those ridges on each edge of the lands seem to leave thin lines on either side of the typically 5R "U" rifling end. I varied speed from 95 to 250 to try and clean that up. Best cut was at 140 RPM.
These edge lines are very faint and after a few rounds will go away. Still, it took me as long to cut this 223 chamber it as does to cut a 33 XC chamber.
For a while there I thought barrel was going to be junk. Given the irony of most things, this barrel will probably be a hammer.
I still hate this brand, but I was able to cut an even chamber that polished out nicely and did save the barrel. We are doing a load development on the rifle, so we'll see how it shoots ourselves......
It was that brand of carbon barrel I REALLY dislike. They are always dirty inside, very crooked, horribly wallowed out at the breech, and button rifled. I think button rifling is a bad idea on a liner for a carbon barrel.
It was hard to dial in as these barrels usually are. It's like the rifling isn't a consistent height. These barrels always need to be scrubbed, which helps some, and I need to cut the rifling out of the breech with the chamber reamer (or a throater) just to have an even surface for dialing near the breech.
I still dial in these barrels just ahead of the throat and about a 1/2" in front the breech. I suppose drill and prebore would work as well, but they would be a terrible choice for end dialers--they are that crooked. They can also give a Grizzly rod a very hard time.
The reamer looked okay, but when I bore scoped after just cutting a little ways, the shoulder looked rough. This was a brand new JGS reamer in .223 Wylde. So I pulled the reamer and went over the flutes at the shoulder with a diamond file--25 micron I think. On subsequent inspections the shoulder looked fine.
However, the big deal was how awful the ends of the rifling looked. Now the rifling in these barrels is always funny shaped. When crossing a land, the Interapid needle jumps up and drops a little, stays relatively even, then jumps up again before falling into the groove. It's like there are ridges on each edge of the lands, with the trailing ridge seeming to be a little bigger. So the end of the rifling often cuts funny.
Well this time, along with the funny rifling ends, the throat wasn't cutting evenly. I thought I should have been past the wallowed out area of the breech, but I pulled the reamer anyway and dialed the barrel in some more. I did get it a little better. That solved the uneven throat cutting, though the rifling still looked funny.
Those ridges on each edge of the lands seem to leave thin lines on either side of the typically 5R "U" rifling end. I varied speed from 95 to 250 to try and clean that up. Best cut was at 140 RPM.
These edge lines are very faint and after a few rounds will go away. Still, it took me as long to cut this 223 chamber it as does to cut a 33 XC chamber.
For a while there I thought barrel was going to be junk. Given the irony of most things, this barrel will probably be a hammer.
I still hate this brand, but I was able to cut an even chamber that polished out nicely and did save the barrel. We are doing a load development on the rifle, so we'll see how it shoots ourselves......
