What the heck is this?

[codyadams]

Ya I'm going to buy a bore scope. It will let me know what kind of throat erosion I have as well. I've never had a carbon ring before. Any tips on removing one?

Iosso, a snug nylon brush, and some elbow grease is where I would start. Monitor progress with your handy new bore scope.

 

[Creedmoor shooter]

Iosso, a snug nylon brush, and some elbow grease is where I would start. Monitor progress with your handy new bore scope.

I'm going to order the teslong. Only 50 bucks on amazon

 

[Muddyboots]

Looks like the bullet from my 300WSM throat that was ugly as sin. I would bet more on throat being severely eroded. Rifles can still shoot OK with throat erosion, as my 300 WSM did but seating bullets became to much of a chore plus I lost my COAL capability in the DM since I couldn't seat them to fit DM and be close to lands anymore.

 

[ntg]

A borescope will tell you quite a bit. If you have a OAL tool like the Hornady, I'd let the bullet sit way back in the neck, put it in the chamber and push it out until it stops. That would tell you a little as well.

 

[Creedmoor shooter]

Looks like the bullet from my 300WSM throat that was ugly as sin. I would bet more on throat being severely eroded. Rifles can still shoot OK with throat erosion, as my 300 WSM did but seating bullets became to much of a chore plus I lost my COAL capability in the DM since I couldn't seat them to fit DM and be close to lands anymore.

Im sure the throat is in rough shape.According to my last measurements I had I only had .20 to go before I was out of my magazine. This is a savage with a 3.005 box mag so that's saying something

 

[Alibiiv]

I'm thinking that the scratches on the bullet are from sliding in and out of the case mouth/neck, and the brass is scratching the bullet not the barrel???

 

[wvelk huntr]

I had similar issue with my 28 Nosler. Ended up being carbon build up in the lead. What tipped me off was an increase in velocity and hard bolt lift. Then it started to get hard to chamber a round so I ejected a loaded round to inspect it and noticed the marks on the bearring surface of the bullet. So I barrowed a bore scope and could see the carbon build up. You can also see from my pictures where the copper transferred when clambering. Several hours later soaking and scrubbing with C4 and it eventually came clean and velocity/pressure returned to normal.

 

[keithcandler]

The hornady OAL tool works a whole lot better with a case you have fired in your chamber, too much slop other wise.

I have the drill bit and the tap for $20 plus $3 postage, you will not regret using a fire formed case on the Hornady.

 

[birdiemc]

The hornady OAL tool works a whole lot better with a case you have fired in your chamber, too much slop other wise.

I have the drill bit and the tap for $20 plus $3 postage, you will not regret using a fire formed case on the Hornady.

I just drill a hole in the case but dont bother tapping it to screw onto the hornady tool, just slip it on and use as you would with a threaded case, it measures just the same, the calipers hold the case against the tool.

 

[highdrum]

You'll love your teslong bore scope. I picked up a tap and bit off Amazon for 15$ to make my own fireformed cases, works quite well.

 

[Creedmoor shooter]

I had similar issue with my 28 Nosler. Ended up being carbon build up in the lead. What tipped me off was an increase in velocity and hard bolt lift. Then it started to get hard to chamber a round so I ejected a loaded round to inspect it and noticed the marks on the bearring surface of the bullet. So I barrowed a bore scope and could see the carbon build up. You can also see from my pictures where the copper transferred when clambering. Several hours later soaking and scrubbing with C4 and it eventually came clean and velocity/pressure returned to normal.

That does look very similar! Did it scratch it bad enough to feel in with your finger nail? I'd never think carbon could be so hard!

 

[wvelk huntr]

I cant honestly say whether it did or not, but my guess would be that it would have. I too have since purchased the Teslong borescope.

 

[highdrum]

That does look very similar! Did it scratch it bad enough to feel in with your finger nail? I'd never think carbon could be so hard!

Diamonds are made of carbon, extremely hard stuff. Carbon rings can be a mofo to get out of a barrel & the lead is a very common place for them to form. That's what this looks like.

 

[Creedmoor shooter]

Bore scope should be here Wednesday. I'll know more then. I'll post pics of what I see