Just got a bore scope, what's up with my bore?

jiffx2781 said:
Since you've had it for a while I'm just trying to figure out if it's one of their barrels from when they were still using cheap Green Mountain blanks.

Hopefully it's not new enough to be one made from an IBI blank. Not exactly sure when they switched.

I was hoping the ones made from IBI blanks would be decent.
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Same


also;


"The Savage factory .223 Remington barrel is pretty typical of what you'll find in most Savage barrels - lots and lots of tooling marks. All button rifle barrels will show evidence of some tooling marks as they are indicative of the process being used, but Savage barrels always seem to be the worst. I can only speculate, but I suspect that this is because they are drilling and pulling the rifling buttons through at a much faster rate (inches per minute) than other manufacturers."


http://www.savageshooters.com/content.php?334-Lyman-BoreCam-Digital-Borescope-Review
 
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Those chatter marks didn't come from a boring button. Those are made by cutters while not using enough lube, in a tight bore.

I've used lots of "cheap" Green Mountain barrel blanks and I have only had one that looked like that. I phoned them and they sent me another, which was fine. They didn't want the bad barrel back and suggested I use it for making pillars.

You might be able to clean up those "tracks" with handlapping with a lead jag. This can be a laborious effort in futility though.

I've never been happy with bores I've had to lap. Especially on a match rifle. Usually they are fine for hunting rifles though.

I have a 30-30Win built on a Martini action with a barrel that looks like the OPs. It shoots very well. The only issue it has is it takes a half dozen fouling shots to get to the sweet spot, which it will hold for the next 20 or so shots. It's a pain in the butt to clean, even with Wipe Out it takes a couple of attempts to clean up properly. One other thing about cleaning it partially and hoping it won't take so many rounds to come around, doesn't seem to make any difference. So I just clean as usual, back to shiny steel.

OP, if that barrel is going onto a semi auto tactical type rifle, I would send it back if you haven't already started working on it.

The supplier should never have sent that out as a match grade example. Has it been machined true to the axis of the bore????

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Marks like that are the result of reamer marks in the bore being ironed out by the button. A cut barrel would have shown the reamer marks more noticeably unless it was lapped or there were no reamer marks in the first place. In my experience, the perfectly reamed barrel is not all that common which is why many makers of buttoned barrels are honing prior to rifling and lapping afterward. Most makers of top-grade cut-rifled barrels lap after rifling. Those who do not will produce some which are smooth and some which are less so. By the way, the most perfect-looking barrel I have ever used was a cut-rifled barrel from Ron Smith. I couldn't find a tool mark in it anywhere and it was as close to perfectly straight as I have ever seen.
A well made barrel will be free of major tool marks regardless of the method of manufacture. However, I have seen numerous barrels which shot very well in spite of being less than perfectly finished inside.
 
Here's a picture of my Savage 116fcss 25-06 I was talking about. When I saw that I was practically horrified. I decided to shoot it and see how bad it would be but to my surprise once it gets some fouling in it the rifle can still shoot minute of coyote out to 400+ yards.

View attachment 233699
 
GMC403 said:
I’ve posted this before,

No borescope needed to see the crap bore on one of my Marlins. Other than it fouling faster than my other rifles, this rifle still shoots above my expectations (especially for a 30-30). It’s hard not to obsesses when you see something like this, but if it shoots well, then its nothing to worry about.

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When did marlin start threading for chokes tubes?
 
rifleman762 said:
It's micro grooving in both directions!
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I was just thinking that, the new marlin micro groove. They should market it as if it is there to displace carbon fouling into the grooves so you have a no maintenance rifle. I suspect there was a damaged tool used in drilling the bore, and then it was compounded in a button rifling.
 
Just got my MRA AR-10 pencil barrel. It looks really good, minus the gas port. The AR-15 must have been a Green Mountain blank.

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Just got my ar10 SPR barrel too and was relieved that the bore looks smooth, similar to yours. Hopefully it shoots sub MOA with match ammo - that's all I really care about.
 
GMC403 said:
I’ve posted this before,

No borescope needed to see the crap bore on one of my Marlins. Other than it fouling faster than my other rifles, this rifle still shoots above my expectations (especially for a 30-30). It’s hard not to obsesses when you see something like this, but if it shoots well, then its nothing to worry about.

Click to expand...

I thought it was just fine threaded...
 
My guess (and it’s only that ...a guess) is these are rings from each hammer blow as the rifling die is pulled through the barrel during the hammer-forging process. I watched a video on this once.
 
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