Results of a bad crown
I was wondering what one might look for on the target if he though he might have a crown issue? I had a really hot shooting 6dasher Krieger barrel that i dragged out of the cabinet 2 weeks ago to play with, and now i cant get the dam thing to shoot. Barrel only has 300 or so rounds on it. Lots of vertical and buck shot type groups at 200 yards. I looked at the crown with my eye glass magnifier but i don't see anything obvious. Looks maybe a little dull maybe? I have several of these dasher barrels so no big hurry on this, but none the less i would like to get it fixed up, if i can determine the problem. I have been shooting this barrel for the last two weeks so i am confident there is an issue. Boy i wish i had an Hawkeye! What does a bad crown look like on paper, if there is any one tall tell sign? thanks Lee
What do you mean by dull? I was given a barrel that had 'quit' shooting after it had been bead blasted and found the muzzle hadn't been sealed when it was bead blasted and a good half inch inside the muzzle had been bead blasted.
Another rifle went south with groups opening up to keyholing in a two week period and the crown looked normal under a magnifying glass, but a .219" pin gage could be inserted 1/2" into the muzzle, while a .218" pin gage would pass through the bore. - nhk
By saying dull, i guess i mean the lands dont look sharp, like they do on my ppc barrels. I dont know really. I will have it looked at. Lee
My Dasher was shooting great, and as the summer progressed I started having to work harder and harder to keep my scores up (500-600yd F-Class) with it. Finally went and took it to the range for some practice and holy cow, it was grouping close to 3/4 MOA @ 300yd! Went home, scrubbed the heck out of it, went back the next day, same thing. Took it home again, scrubbed it again, and checked my seating depth. The throat had moved out just enough that instead of being firmly jammed in the lands, I was right at 'kissing', which it obviously didn't like. I seated the bullets back out and the groups tightened down again.
Dunno if its the same problem you are having, but it might be something to look at if you haven't already.
Thanks Monte but i have checked the jam a few times now. I think i dinged the crown. I have an old leather gun case that i liked real well and it finally blew out one day this past spring while this barrel was in it. i didnt think it hit anything but i cant be sure. I am going to recrown and go from there. im sure it will fix it right up! I have several of these dasher barrels so no big deal. I just wondered if a bad crown had any particular characteristics as far as spitting shots or going vertical or anything that one can look for while diagnosing the situation. No sweat! Thanks to all! Lee