I have a Remington 700 hvy bbl in 22-250.  I want to change it to 308.  
There is the option of changing the bbl or reboring.
Has anyone here done either and who did you use?

Nick,

I think instead of reboring, you'd probably be better off buying a take-off barrel in .308.  Your gunsmith would have to reset the headspace for your action, but that's going to be a good deal cheaper than having to rechamber and rebore your current barrel.

Another option would be to buy a pre-contoured barrel, or even a bored blank, from a good barrel maker (Shilen, Douglas, Lilja, etc.) and have it chambered and contoured to your specs.  You'll end up with a great barrel, and probably still spend less (just guessing, I've never priced reboring) than doing all that work to your current barrel.  Unless you have some sentimental attachment to your current barrel, I can't see any justification to reboring it.

As to gunsmiths, it depends on your expectations.  If you're building a benchrest shooter, your choices are narrowed considerably.  Otherwise, most well-equipped shops should be able to rebarrel your action with either a take-off barrel, or an "aftermarket" barrel with good results.  I did have the name of a company that rebores and rifles barrels, and if you're set on going that direction, I'll try to find the info again.

Quoted: I have a Remington 700 hvy bbl in 22-250.  I want to change it to 308.   There is the option of changing the bbl or reboring. Has anyone here done either and who did you use?

The bolt face on both rounds is identical so a conversion is as easy as a barrel change. I'd suggest an aftermarket barrel for best performance. Talk to a reputable gunsmith, there are many options out there. A Brownell's catalog should list most of them.

Reboring costs roughly the same as a rebarrel job. To me, reboring would only be advantageous if there were certain factory barrel markings that you wanted to preserve. At any rate, Brownell's lists some Shilen threaded factory contoured barrels for the 700 (apparently they are a new product). That should save you some money on installation. For .308 WCF the product numbers are 801-782-308 for a .308 Win 1-10 Twist Varmint Contour CM Barrel ($206.25 retail/$165 dealer) and 801-783-308 for a .308 Win 1-10 Twist Varmint Contour SS Barrel ($291.25 retail/$233 dealer). I'm assuming that the CM barrel is in the white, so figure some additional cost for bluing ($45 from Glenrock Bluing). Plan on spending around $100 or less for labor on just the installation (gets more expensive if you have a custom contour made or have the barrel made from a blank).

Here's Shilen's description of these barrels from their 'site.

Thanks much.
Looked through Brownells a week ago and did not see the barrels that are mentioned here. I guess I'll have to give them a call.