You'll probably need to remove the hand guard to install the rail, anyway.

I put a Magpul MOE hand guard on my Sport. GunKings has them for $28 with free shipping. They also have the rails. If you buy both, they put the rail in the MOE package and ship both for free. I bought the hand guard and a 7 slot rail for a total of $34.60 delivered by first class mail. Took about 4 days to come in.

The hand guard that comes with the Sport doesn't have a heat shield. The Magpul has an aluminum heat shield and has ears on the front that extend over the FSB to prevent your hand from touching the FSB, which also gets hot.

This is the link to the Magpul MOE at Gunkings:

Magpul MOE™ Carbine Length Hand Guard Black (Free Shipping) [MAG440BLK] - $28.00 : Gunkings, 10-22 and AR15 parts and accessories

7 slot rail link - http://www.gunkings.com/index.php?ma...oducts_id=1177