I use the Redi-edge sharpner. You can buy it at cabelas. It takes about 20 strokes on each blade to get the heads sharp the first time. Then just a few strokes will touch up the blades quickly. I also use a piece of leather to "strope" the blades to shaving sharp edge. It also makes a great knife sharpner, and does a good job of getting rocket blades sharp.

TAKE YOUR KIDS HUNTING AND YOU WON'T BE HUNTING FOR YOUR KIDS