Does my freebore look weird?

[Ice-kub]

Was having some trouble with some handloads for my 7 wsm, it's on a long action 700. Provided a dummy round to the gunsmith. 175gr berger elite hunter seated with boattail junction seated at neck shoulder junction. Measured 2.450 cbto with comparator. Had rifle about two years now and have been having trouble chambering rounds unless cbto is less than 2.350 cbto, anything longer and I get scuff marks on the bullet around the entire shank just north of the case mouth. Finally bought a bore scope to see what's going on. I don't believe it's carbon ring.

Could it possibly be that the reamer didn't actually cut away all the rifling in the freebore based on the photos below?

I also could be seeing things as I do specifically remember him telling me it would get chambered when his reamer returned from "sharpening"?

 

[The Guide]

Was having some trouble with some handloads for my 7 wsm, it's on a long action 700. Provided a dummy round to the gunsmith. 175gr berger elite hunter seated with boattail junction seated at neck shoulder junction. Measured 2.450 cbto with comparator. Had rifle about two years now and have been having trouble chambering rounds unless cbto is less than 2.350 cbto, anything longer and I get scuff marks on the bullet around the entire shank just north of the case mouth. Finally bought a bore scope to see what's going on. I don't believe it's carbon ring.

Could it possibly be that the reamer didn't actually cut away all the rifling in the freebore based on the photos below?

I also could be seeing things as I do specifically remember him telling me it would get chambered when his reamer returned from "sharpening"?

Show us a cartridge that you have colored the bullet with a black sharpie and then chambered and extracted. Push in on the cartridge on the way out so that the ejector doesn't force it against the side of the action or chamber on the way out.

Jay

 

[BBob]

Scuffs like this? If so it's usually normal.

Is this ring on my jacket rifling?

I am getting a ring mark on the jacket of my bullets after chambering. Still pretty new to reloading so just wondering if anyone knows of this is the rifling? I tried marking up with a sharpie too and could not see any engraving. Thanks!

rokslide.com

Is this ring on my jacket rifling?

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”...

rokslide.com

 

[Ice-kub]

I covered one in sharpie.

Also, along with being hard to chamber, it's quite tough to extract and pull the bolt back and eject the round

 

[The Guide]

I covered one in sharpie.

It is inconsistent and doesn't look like it has sharp edges like it was made by metal. How many rounds on the barrel?

Jay

 

[Ice-kub]

It is inconsistent and doesn't look like it has sharp edges like it was made by metal. How many rounds on the barrel?

Jay

It's got 200 and change on it.

 

[The Guide]

We're you ever able to use cartridges @2.450" since you got it?

Jay

 

[Ice-kub]

We're you ever able to use cartridges @2.450" since you got it?

Jay

Yes, I was. With FL sized brass, this is neck sized. Maybe I'm crazy, I'll full length size one and try it at 2.450 and report back.

 

[The Guide]

My wife has a 7mm-08 that got a serious carbon ring after less than rounds using Superformance. Had to do a full 24 hour soak with Boretech Eliminator to remove all the fouling.

Jay

 

[TaperPin]

That black in the bore looks a lot like hard carbon buildup. What is your cleaning routine?

 

[Ice-kub]

It's the same with a fl sized. Took before and after one chambering.

 

[Ice-kub]

That black in the bore looks a lot like hard carbon buildup. What is your cleaning routine?

I use patch out, put a couple soaked pads down the barrel, sit over night and then dry patches. Couple more wet ones go through, sits for an hour amd they come out clean.

I'm also not convinced it's carbon by the way it looks. Almost looks like rifling that wasn't cut down all the way in the chambering process? I'm not 100% but shouldn't there be a bit of bore after the case mouth that is rifling free?

 

[gbflyer]

How does it shoot?

 

[TaperPin]

I’ve heard of guys using patchout and it works well for copper fouling, but they also use something else to help with carbon buildup. A lot has been written for and against using bronze bore brushes, some barrel makers say use it and others don’t. Same for abrasive cleaners like jb bore paste. I’d try a different solvent that’s tougher on carbon, like one of the guys above have used, and then you might have to go to an abrasive on a patch like jb. The nice thing about jb is you don’t have to do the entire barrel - just go back and forth for the 6” or so in front of the case neck. it’s nice that you have a bore scope and can watch progress on the cleaning.

One of the reasons I’d say it’s carbon buildup is the rifling lands don’t leave distinct impressions on the bullet and its a condition that wasn’t there when the barrel was new.

 

[Wrench]

If you look right behind the bushings, you can see the taper into the leade. Yours is holding up pretty well for 200rds of high horsepower.

 

[Wrench]

The throaters have a much slower taper.

 

[Ice-kub]

How does it shoot?

It was shooting well, half moa allllllll dayyyy haha, biggest three shot group it ever shot during load dev was just over an inch. Just reallllyyyy tough to eject a loaded round.

I’ve heard of guys using patchout and it works well for copper fouling, but they also use something else to help with carbon buildup. A lot has been written for and against using bronze bore brushes, some barrel makers say use it and others don’t. Same for abrasive cleaners like jb bore paste. I’d try a different solvent that’s tougher on carbon, like one of the guys above have used, and then you might have to go to an abrasive on a patch like jb. The nice thing about jb is you don’t have to do the entire barrel - just go back and forth for the 6” or so in front of the case neck. it’s nice that you have a bore scope and can watch progress on the cleaning.

One of the reasons I’d say it’s carbon buildup is the rifling lands don’t leave distinct impressions on the bullet and its a condition that wasn’t there when the barrel was new.

I will definitely try some of that stuff mentioned above. Wipeout/patch out says it takes out carbon but who knows. I'll give something else a try. Don't like the idea of that abrasive stuff.

 

[Ice-kub]

If you look right behind the bushings, you can see the taper into the leade. Yours is holding up pretty well for 200rds of high horsepower. View attachment 615339

Well I'm glad to hear that. It sure hold onto that bullet when it's chambered. Would sharpening the reamer have caused a slightly smaller throat? When I first started loading for this rifle I thought I was in the lands but I'm wondering if it was just the throat now?

 

[Wrench]

Reamer sharpening can be a trick to keep dimensions.

 

[Ice-kub]

Reamer sharpening can be a trick to keep dimensions.

I don't know how you would sharpen it without changing dimensions. Is there a way for a smith to measure the dimensions of the throat to see if it is in fact undersized?