I have the Aitchisson kit, jams all the time. Any experience with a 22LR dedicated upper on a M-16? thanks!

Might want to check out Compass Lake Engineering, Mr. Frank White. He does one that definitely works and will shoot w/ most small bore match rifles. Believe their site is www.compasslake.com

I understand that some of the tactical people have a builder they like, but I wouldn't buy a .22 upper from anyone other than Compass Lake or Derrick Martin.
I believe they both use a modified Army M-261 kit.

I have with a 24" match barrel, flat top and front of barrel bachined for match sites. Two mag. I may be willing to part with Pm if interesred.

JD

thanks guys!