I have an A3 Upper that I would like to put a 3-9 x 40 scope.  It's a 20' HB which I plan to use for shootin critters.

Questions:

1) Should I bother with a mount or should I put the rings directly on the upper receiver?

2) Can anyone recomend some good rings?  I probably need high ones so that the front of the scope doesn't hit the handguard.

The ARMS #22 High rings are (IMHO) the best rings you can get for an AR. Kinda pricey at around $90 a set, but they WILL remove and replace without losing zero, and when mounted directly on an A3 receiver, they position the scope at the same height as standard iron sights, so no cheekpiece is needed. If you put a scope which has a 1-inch tube in 'em, you'll also need the 1-inch inserts, which will run $30 or so. BUT, that $120 to mount the scope is money VERY well spent, trust me.

Thanks for the reply Wizard, do you have the 1 inch inserts in yours?  Just curious as to how well they work.  Don't want the scope to shake loose.

Thanks Troy,
U Da Man!!

Just got in from work.....