Here's the short layman answer:
Yes, but it's expensive.
Normal railed handguards still "clip on" to the rifle, using the factory delta ring, and the sheet metal bracket right behind the front sight tower.
If you want a rail longer than that, it will have no forward attachment point. So, you'll need a free-float handguard.
These involve removing the factory (spring-loaded) delta ring that holds factory-type handguards on, and replacing it with a large fixed, threaded nut that engages the free-float handguard more firmly, and clamps it against the receiver.
This allows you to hold the weapon by the handguard which is only attached to the rifle on one end, and bang it around, without upsetting the handguards mount.
The obvious question, though, is why you want a longer handguard on a carbine? how much shit are you going to put on the rail system?
If you just want something that projects further forward, like a weapon light, there are many good small rail sections that bolt through sides of the front sight tower and give you about an inch of rail on either side. Midwest industries makes a good one: http://www.midwestindustriesinc.com/ind ... gory_id=94
At $35, its far cheaper and lighter than a free-float handguard, and if you're just looking for somewhere to put a light or laser, its a far better solution.
MF'N TEAM LEADER
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