View Full Version : Convert high cap 5.56 AR mags to 6.8?

04-28-2009, 9:36 PM
I have legally acquired standard capacity AR mags back in the 90s. They're all for the AR in 5.56x45. I was wondering if I could change the followers to work with 6.8 SPC rounds? To me, the only difference between the 5.56 and 6.8 mags are the followers. Would it be legal for me to change the follower on a legal 5.56 30rd mag to work with 6.8 SPC?

04-28-2009, 9:43 PM
I think the feeding lips are also modded for the 6.8 SPC.

Bottom line, as long as the original rounds function then there is no problem. However, .223 does not function well in my 6.5 Grendel mags (and I am told they are the same as 6.8 SPC.

04-28-2009, 10:12 PM
Last I checked the feed lips are different on the 6.8

Ten Rounder
04-28-2009, 10:39 PM
If 5.56 mags worked for 6.8, then why do they sell 6.8 mags.

6.8 mags are very different. The internal ribs are shallower and the feed lips are wider too.

Using 6.8 in a 5.56 mags the rounds are too crowded after 4-5 rounds and begin tipping. You will not be happy doing this either. Think FTF.