Not sure what happened. I had PT&G regrind a 6 BR reamer to no freebore. It has been used 3 times previously and these guns shoot nicely. The Kreiger barrel chambered with same reamer with no freebore would not shoot. I seated a bullet well into the lands and examined the engravings...Not Good! The 12:00 and 3:00 lands were twice as long as wide BUT the 6:00 and 9:00 engravings were barely noticeable! If the bullet was seated .010 deeper, the 6:00 and 9:00 engravings were gone. My gunsmith is a perfectionist and has never chambered a crooked chamber for me. Can a barrel have an internal defect like a void/bubble? Gunsmith doesn't cut any barrel off chamber end as he does at muzzle. Borescope did not reveal anything gross. Anybody seen this?
Uneven lands after chambering with reground reamer
- Thread starter lpreddick
- Start date
Dusty Stevens
Shiner
You either got a bad regrind or the gunsmith cut his first barrel crooked. An examination of the reamer will tell the story
Tim Singleton
Gold $$ Contributor
the bore scoping showing no signs of a problem makes me wonder a little
Did you scope it? If it is a bad grind or a bad setup by the smith either one would show up with the bore scope
Is your loaded ammo straight?
Did you scope it? If it is a bad grind or a bad setup by the smith either one would show up with the bore scope
Is your loaded ammo straight?
I'm not sure that any issue with a reamer could make it cut longer on one side of the throat than the other. Even if it only had one flute cutting, it'd still cut all the way around the bore.
I'm betting on a barrel issue.
I'm betting on a barrel issue.
ridgeway
Silver $$ Contributor
I got a reamer going back with a similar issue. It's not cutting the end of lead perpendicular to the lands. I cut a chamber and 2 stubs...all similar shape as pic below. All 4 lands are cut uniform, but not perpendicular. The two stubs were different barrel makers and did the same thing. Not as bad as the picture below.
Attachments
Tim Singleton
Gold $$ Contributor
thats what i was thinking if it is a barrel or reamer issue it should show up with a bore scope
Dusty Stevens
Shiner
Is this a brand new barrel?
DCRYDER
Silver $$ Contributor
I've got to agree, can't see how this is a reamer problem. Seems to me that the rifling is taller one one side or the reamer is getting pushed backwards when cutting fluted come in contact with the lands.
This isn't a ratchet rifled barrel is it? If the riflings are canted it would cause this.
How does your smith set up for chambering? Is he cutting the whole thing with the finish reamer from start to finish with a proper fitting pilot? Is he pre drilling and then pre boring before using the finish reamer?
More than likely, it's either the barrel or setup issue. This is why it's good to check your work as you go IMHO.
My guess is your smith will be more than happy to check it out and correct it.
More than likely, it's either the barrel or setup issue. This is why it's good to check your work as you go IMHO.
My guess is your smith will be more than happy to check it out and correct it.
I'm leaning this way.
Good news. My smith set barrel back a little and rechambered using all skills he possesses. Borescope looks perfect...4 land's slopes look the same. Engraved a bullet at .020 into lands and I get 4 equal marks. Shot proven loads yesterday and grouped in the two's! I suspect this was a barrel issue...Not sure what but a lesson learned...If a gun is not shooting and all other variables are optimal, engrave a bullet at max into the lands, then seat it gradually to be sure lands are equally engraving. If you jump bullets and your lands are as these were, imagine the bullet hitting two adjacent lands, then the other two...Thanks for your responses.
Tim Singleton
Gold $$ Contributor
May not have cut enough off to get completly out of the lapped area
Glad it's shooting !
Glad it's shooting !
shortgrass
Silver $$ Contributor
Little to none! Work hardening barrel steel is a myth, IMO. Unless, of course, your tools are dull and you don't have sense enough to know it, or you just plain don't know what you're doing.......... Again, Machining 101 !
Last edited:
dmoran
Donovan Moran
The only chambers that I have seen that do not have work hardening rings are those that were single point cut. Unlike reamed chambers, were work hardened rings are always obvious.
Donovan
Exactly. Probably a barrel issue.
But, but, but...
It's basic machining, whether it's on a barrel or a piece or cold rolled doesn't matter. It seems that there are people with lathes in their basement claiming tolerances, day in and day out, that are better than professional tool and die shops and that, logic nor real experience has no place here.
Chambering a barrel is basic machining. There is no magic pill and no super human gunsmith in existence.
This is coming from someone who has done both and built multiple world record holding rifles.
No, just because your calipers have .0001" or .0005" resolution, does not mean they are that precise, by a long shot.
I wouldn't want to be a barrel maker.
Dusty Stevens
Shiner
you mean you wouldnt want one of your barrels back after somebody drove a lead slug thru it and told you it sucked?
Lol! No, but my point was, I wouldn't do well at tolerating someone telling me that the bore measures wrong, because they checked it with their digital calipers that have 5 decimal places of resolution.
...for example
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