Neck size error danger
I took a used 6.5 x 284 BR rifle to a gunsmith who is in fact a competition BR shooter/champ. I knew the rifle had some flaws but I wanted to shoot it just to learn and have fun.
I had a cerro safe chamber casting done and all I wanted to know was could the gun shoot factory ammo until I changed out the barrel. He said yes I could but it would be a tight neck but no real problem. I might have to clean it every couple shots. OK. Just s tight neck.
I have some of the brass fired thru the rifle b/4 and with a micrometer the neck size is .291-.292. Clearly it was turned. Like a dolt, I never really asked what the chamber casting measured, I just assumed stock ammo would be OK, because I was told by a smith it would work. Stock brass neck for a 6.5 is .296. By admission I should have been more discriminating and done the math myself but when I called the smith back to ask about his measure of the neck he said it was .294 -.295. He still has the casting.
Those numbers don't seem to work. Trying to fit a .296 measure into a .294 measure seems dangerous.
I had a cerro safe chamber casting done and all I wanted to know was could the gun shoot factory ammo until I changed out the barrel. He said yes I could but it would be a tight neck but no real problem. I might have to clean it every couple shots. OK. Just s tight neck.
I have some of the brass fired thru the rifle b/4 and with a micrometer the neck size is .291-.292. Clearly it was turned. Like a dolt, I never really asked what the chamber casting measured, I just assumed stock ammo would be OK, because I was told by a smith it would work. Stock brass neck for a 6.5 is .296. By admission I should have been more discriminating and done the math myself but when I called the smith back to ask about his measure of the neck he said it was .294 -.295. He still has the casting.
Those numbers don't seem to work. Trying to fit a .296 measure into a .294 measure seems dangerous.
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My first question would be, what are you using to measure with? Dial calipers, Vernier, Digital? when was the last time they were checked against a known measurement?
If the neck was indeed that tight you should at least have the primers flattened so they look like they are one piece with the case head/rim. It should have popped a primer or two. Was it hard to extract? It should have been hard to chamber a round.
We need more specifics.
Best0 -
First, a loaded round with a .296 neck will not chamber in a .295 chamber. It is dangerous to shoot a round that does not have .0015 to .003 clearance. The bullet cannot release easily causing higher than normal chamber pressure. The signs should be evident. ie, sticky bolt opening, flattened or cratered primer dent etc. Usually, tight necked chambers are inscribed on the barrel by most good gunsmiths. If the brass after firing does not accept a new bullet easily without sizing, the chamber neck is too tight for that brass. Neck turning is needed. There is a normal "spring back" after firing of the brass neck after it contacts the chamber wall of about .001. Therefore, if you measure .292 on fired brass, the chamber neck should be .293 to .294. Bob 0 -
Any sane gunsmith should know better than to tell a customer a tight necked chamber can shoot factory ammo, find a new smith before you get hurt..... 0
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