For starters, I already have a Colt 6920 and a Krebs AK that are my dedicated 5.56 and 7.62 shooters, respectively.  My next project is building up a top-quality stripped lower for swapping other-calibers uppers such as .50 Beowulf, 6.8, etc.

(1) Do I need a Multi lower such as Stag, MEGA or POF Billet, or will a Noveske 5.56 lower function just as well for these >5.56 calibers?

(2) Are there any legal issues (particularly federal) if using a non-5.56 upper with a 5.56 lower?  (The reason I ask this is that a salesperson seemed to think there was.)

(3) Do Multi lowers use the same LPK and trigger groups as the 5.56 lowers, if I go the Multi lower route?

Thank you in advance for your responses.

Quoted: (1) Do I need a Multi lower such as Stag, MEGA or POF Billet, or will a Noveske 5.56 lower function just as well for these >5.56 calibers?

No, aside from the rollmark they are the same.  

(2) Are there any legal issues (particularly federal) if using a non-5.56 upper with a 5.56 lower?  (The reason I ask this is that a salesperson seemed to think there was.)

No, your 5.56 lower is fine.

(3) Do Multi lowers use the same LPK and trigger groups as the 5.56 lowers, if I go the Multi lower route?

Yes, same lower receiver dimensions, same LPK.




ETA - Welcome to the boards.

If you are doing a top quality lower build I recommend the slr15 lower.  There is a group buy on until the end of the month.  

Quoted:

Interesting screen name...


Welcome! And see 2 above for all your answers. He's got them exactly right.

Thanks for the replies, everyone.  Noveske N4 stripped lower en route.