Blackfork
Member
Took three uppers over to a buddy's house today to look at them with borescope. Two were pretty well used with competition loads. One has less than 1000 rounds on it, the fourth was an unfired Compass Lake belonging to my friend with the borescope
The two 4000+ round uppers had throats and rifling that looked like alligator skin or cracked and flaked dried lakebed. It also looked like the pattern of cracks was drifting down the barrel. Nothing was 90 degrees. Some flakes missing. Lots of copper in the cracks and crevices. Both of them gauged 5-6 on a throat erosion barrel. They had been carefully cleaned with dewey rods and bore guides all their lives. Down the barrel and at the muzzle the rifling looked normal and sharp. The gas port had a teardrop shaped drag mark coming out of it.
The 1000 round upper looked fine, though you could see some striations that looked like cutting tool "chatter" in between the riflings. The throat gauged a 1.
The New Compass Lake with an unfired Krieger Barrel looked clean. All the edges were sharp. No tool marks. The rifling all started at the same place and had a sharp edge left where the chamber tool cut it.
I shot one of the 4K barrels last week at Panola. It shot OK up close, 192X3 standing, 193X10, (with a weird 8) sitting. 194X5 at 300 prone. At 600 it was a total disaster. Some shots were on call, most weren't. You couldn't predict where it was going to shoot. I shot several eights and two sevens. 176X1 I think.
I'm rebarreling, or limiting that 4000 round rifle to Infantry Trophy and practice only. Going to try and limit use of my 1K rifle to save it for big matches only, and Camp Perry. The other 4K rifle belongs to someone else. I'm suggesting he rebarrel it.
The two 4000+ round uppers had throats and rifling that looked like alligator skin or cracked and flaked dried lakebed. It also looked like the pattern of cracks was drifting down the barrel. Nothing was 90 degrees. Some flakes missing. Lots of copper in the cracks and crevices. Both of them gauged 5-6 on a throat erosion barrel. They had been carefully cleaned with dewey rods and bore guides all their lives. Down the barrel and at the muzzle the rifling looked normal and sharp. The gas port had a teardrop shaped drag mark coming out of it.
The 1000 round upper looked fine, though you could see some striations that looked like cutting tool "chatter" in between the riflings. The throat gauged a 1.
The New Compass Lake with an unfired Krieger Barrel looked clean. All the edges were sharp. No tool marks. The rifling all started at the same place and had a sharp edge left where the chamber tool cut it.
I shot one of the 4K barrels last week at Panola. It shot OK up close, 192X3 standing, 193X10, (with a weird 8) sitting. 194X5 at 300 prone. At 600 it was a total disaster. Some shots were on call, most weren't. You couldn't predict where it was going to shoot. I shot several eights and two sevens. 176X1 I think.
I'm rebarreling, or limiting that 4000 round rifle to Infantry Trophy and practice only. Going to try and limit use of my 1K rifle to save it for big matches only, and Camp Perry. The other 4K rifle belongs to someone else. I'm suggesting he rebarrel it.
