That one looks promising
http://www.mrbulletfeeder.biz/
.223/5.56:
The small rifle calibers are not yet available, but will be after the summer, we expect to start shipping rifle caliber bullet feeders by September 2012. A new dropper system has been developed to handle these very small and light bullets, and their performance is every bit as good as the pistol calibers. Especially with these small and difficult to grab bullets, a bullet feeder is a must have item.
.308/7.62:
The large rifle calibers will also be available later in the year. Note that the rifle calibers do not include or require a custom powder funnel.