I'm looking for a new project and pretty much have my sights set on a piston system. I have found a supplier for HK 416 components. Just wondering if anyone has experience with the components and their fit in anything other than a HK upper. I've used a 10.5 416 so I know it pretty well from an operator standpoint, just wondering if anyone has ever heard of someone retro-fitting another mfgr's upper to use it.

Cheers

PS here is the supplier, if anyone has any info on them as well...

http://www.hkparts.net/416%20417.htm?wwparam=1222200081

Thanks!