how many rounds have you guys put through a non-chromed barrel? my mini-14 dont have one but I havent had a problem yet but it only has about 1500 rds throught it

I'm intersted in the reply to this as well.  I've never heard of anyone wearing one out, chrome or not.

Depends on many factors.  Twist rate of barrel, type of ammo used (i.e. sammi vs NATO), and how you shoot (lots of rapid fire, bump fire, or slow fire), how hot do you let the barrel get?

Not to mention at what accuraccy level?  If you can tolorate larger groups the barrel will last 'longer' - if you only want tiny little groups you'll replace it sooner.

Barrels can last as few at 5,000 round or as many as 80,000 rounds for an unlined barrel.  Given identical usage a chrome should last roughly twice as long - but unless you're in a lab environment I don't see much 'identical usage'.