I bought a used 338/06 last week that was built on a Ruger M/77 tang safety type action. The price was good (about what the action, rings, and B&C synthetic stock were worth), so I thought that I could use it for rebarreling if it didn't shoot well (and I already have a338/06 on a VZ 24, so it wasn't a problem to come up with ammo to try in it before rebarreling).

On cleaning of the barrel I noticed a series of circumferential grooves for the first inch or so at the muzzle end of the bore (sort of like threads). I assumed that this might have been done in the process of crowning the barrel(not a great job, as it seems a little less than smooth). I considered cutting the rough area off and recrowning, which would bring the barrel down to about 21 1/2", but I decided to shoot it first just to see how bad it would foul. Today I took it to the range.

The best load was with 225 grain blems from LSB (appear to be Hornady) and RL 15 (groups from 5/8 to 7/8 at 100 yards). The other loads were in the 7/8 to 2 inch range (Sierra 250 BT's, Nosler 180 and 200 grain Ballistic Tips, and 250 grain Hornady, with RL 15 and IMR 4320). Not great, but a reasonable start.

Altogether I fired 30 shots, and expected a heavily fouled barrel in the rough area near the muzzle. Imagine my surprise when I started to clean and found that there was no more fouling than most "normal" barrels (just a FEW copper traces here and there, but not nearly as much as several other rifles that I have).

The circumferential grooves are fairly noticeable, and the really weird part is that they are in the bottom of the barrel grooves as well as the tops of the lands, but they do not extend all the way to the bottom of the lands, so it seems strange that they should be in the grooves at all. It almost looks like chatter from the rifling process, but I have no idea who made the blank or who did the rebarrel so I am a bit in the dark about what might have gone on. I can only see them in the first inch or so of the barrel, but I don't have a bore scope to check for other patches further toward the chamber.This might even be a projact to play around with fire lapping before rebarreling .

My real question is whether anyone else has had a large rough area like this in a barrel that seems not to foul heavily? Any comments ? The only other firearm that I have had with similar grooves in the barrel was a Ruger Super Blackhawk 44 Mag that had similar marks the full length of the barrel from the factory, and it fouled so heavily that I rebarreled it.

Jim

Sounds like bore reamer marks from before the rifling process. I bet it is a botton rifled barrel. Its hard to guess, but I'd say the possibility that it is a Douglas is not off. They do not pre-lap their barrels before they get rifled. This means all tha marks form the post drill reaming are "smoothed out" in the rifling process. I think it is cutting a corner. They ought to be lapped. As far a firelapping goes, I personally do not care for it. I would rather hand lap it and either keep the lap out of the throat, or re cut the throat after it is lapped. If you can live without lapping it at all, do it. If the accuracy you are getting is acceptable to you, then leave it. The groups you posted might be the best the barrel will do regardless of the marks. The lapping isn't going to do a lot for you except add pre-mature wear to the barrel. The marks you see are not a sure sign that you'll see added fouling. Sometimes, those barrels will still work.

First; If the rifle shoots ok and dosen't foul don't worry, be happy.
Second; the "grooves are probably not very deep, they just look "bad".
Thirdly; They are concave, not convex so the bullet will not touch them anyway.

Take Care!

Don't rebarrel, don't lap, just shoot......