Is this ring on my jacket rifling?

[BBob]

Well look at that! Freshly chambered 6.5CM and an old AMAX. Note the scuffs at the front of the bearing surface and further down on the side of the bearing surface all from the throat. SAAMI reamer and not a fat bullet at all and off the lands with that .199” freebore. Bullet is dead on .2640” with a tenths indicating mic. This is common stuffing something that’s less than .001” smaller than the hole you’re trying to stuff it into. I’ll bet I have more examples of this on my bench if I care to dig them out. Shoot that thing and the sharp edge at the neck throat transition will erode and round off and this etching will likely go away.

Oh and you can also see the seating stem mark further up towards the top of the bullet. That'd be a Redding Comp Seater w/VLD stem.

 

[35WhelenAI]

That pic shows a good example of what you have described, thanks for taking the time. The scuffs down the side are a given on most live rounds extracted.

IMO, plunger force would not make the defined ring around the entire bullet.

OP, how many rounds have you put through the gun before noticing this, and were any rounds shot with this batch of bullets?

 

[Lawnboi]

You should see my dummy rounds. They are beat to piss from ejecting

 

[Outdoorsman12b]

Well look at that! Freshly chambered 6.5CM and an old AMAX. Note the scuffs at the front of the bearing surface and further down on the side of the bearing surface all from the throat. SAAMI reamer and not a fat bullet at all and off the lands with that .199” freebore. Bullet is dead on .2640” with a tenths indicating mic. This is common stuffing something that’s less than .001” smaller than the hole you’re trying to stuff it into. I’ll bet I have more examples of this on my bench if I care to dig them out. Shoot that thing and the sharp edge at the neck throat transition will erode and round off and this etching will likely go away.

Oh and you can also see the seating stem mark further up towards the top of the bullet. That'd be a Redding Comp Seater w/VLD stem.
View attachment 494230

Thanks man this is what I was thinking.

 

[Outdoorsman12b]

That pic shows a good example of what you have described, thanks for taking the time. The scuffs down the side are a given on most live rounds extracted.

IMO, plunger force would not make the defined ring around the entire bullet.

OP, how many rounds have you put through the gun before noticing this, and were any rounds shot with this batch of bullets?

It’s a brand new gun.

 

[35WhelenAI]

Thanks on the info on being a new gun. Look forward to bullet measurements and if it's the same bullet in the factory load that didn't do it. Good thread, just doesn't sit right with me that a factory load was fine. All else being good info, it seems to be coming down to the bullet IMO.

 

[Outdoorsman12b]

Thanks on the info on being a new gun. Look forward to bullet measurements and if it's the same bullet in the factory load that didn't do it. Good thread, just doesn't sit right with me that a factory load was fine. All else being good info, it seems to be coming down to the bullet IMO.

Looking back on it I only tested one factory loaded round and I did not really thoroughly inspect to say conclusively it did not happen. In any case I shot the last rounds from that box of bullets so will be on to another one.

Now if anyone has been following along that has expertise on whether or not the rub on the copper jacket may cause irregularities on expansion would be great to hear. I am not concerned about the one time mark but rather repeated wear from chambering.

 

[Caseknife]

My thought is that you would have to chamber the same round hundreds of times to cause any appreciable wear that would cause the bullet to fly erratically or the jacket to come apart, if it would happen at all.