In a bit of a quandary.

Rifle is a ZG47 in 30-06. Original barrel cut to 21". Very pitted inside with immensely long throat. Suffers from excessive headspace manifested in case stretch and care needed in sizing. Despite issues it is very accurate indeed. It's also slow - 2,650fps with 180s, 2,720fps with 165s.

I have two schools of thought on this.

1. If it ain't broke don't fix it. The headspace is manageable and it's possible I may only gain 100fps which I won't practicaly notice.

2. I'm lugging around a 308 with excessive headspace

If I do rebarrel it will remain a 21" 30-06.

Have you actually measured the headspace or are you overly sizing your brass?
If the barrel is pitted and has a long throat, then you might want a new barrel.
But you are right; won't gain much. Just depends on if you want to spend some money. As long as it shoots well, who cares? But you?
I would rebarrel just for the pitting thing.

If it bothers you to take the extra care (the headspace issue) then get it re barreled.
I probably would.
Tempting to leave it alone if it is accurate.
I would not consider the velocity as a reason for re barreling it is really accuracy that matters. ( in my opinion)

I find that most "headspace" "issues" are in the minds of the shooters. Where does the bolt handle fall on a field gauge? That is the only measure.

Been there. Had a Ruger which shot very well but which had noticeable pitting in the bore. Unable to live with this, I re-barreled it with a highly rated custom barrel. It never shot as well again but looked great doing it.
I once barreled a 375 H&H for a friend of mine. Rifle was a real tackdriver but the Shilen barrel showed numerous tiny dents at six o'clock in the bore. Possibly a result of unburned ball powder granules. Unable to keep using the flawed barrel, he had me put on a new Shilen. All went well and the barrel looked great. Still shot OK but group size increased by about 75% so not the tackdriver it used to be.
Your choice but, if you are able to work around the possible headspace issue, I would leave it be. Regards, Bill.

I don't care about the headspace really provided it's safe. I've shot it for 10years like that and only made the mistake of shutting it on guages a month ago.

I don't give a damn about the pitting and it's most accurate if copper is left in the bore.

It shoots 180gr ABs into 0.3moa repeatably at 2,650fps.

I think I'll leave it alone.

quote:

I think I'll leave it alone.

Good choice

Yes, good choice; just fit the brass to the chamber and carry on. A new barrel probably wouldn't shoot that well.

It's done similar with 165gr ballistic tips. I also have 300 cases 'fitted' to it. I find it rather amusing that a 58year old barrel with such issues should be this accurate.

20150913_133246 by adshools, on Flickr

That is not particularly slow for a 21 inch barrel to start with.

With a long throat you should be able to get more velocity by seating the bullets out and using more powder if they will fit in the magazine and they probably will as that was practiced by many Mauser manufacturers..

Always fire form cases before anything else with such a gun, and not a bad idea on any gun.

Same velocities I get out of my BLR in .308 with 20" barrel--my favorite hunting rifle. Leave well enough alone.