Well it would have to be an AR length cartridge so that rules out most of what you've got, but a .308 length RDB to replace the RFB chambered in 6.5 Creedmoor would be cool. For now a 6.5 Grendel RDB would be pretty cool. But given the broken bolts experienced with AR bolt heads and KT's quality control, I think it would be a disaster. I've never broken a bolt on the couple 6.5 Grendel AR's I've owned, but I know it can be an issue.Or 6.5 Creedmore,
Or .270 Winchester,
Or .300 WSM,
Or .300 AAC,
Can't do .308, the RFB owns that one:kiss:,
Even the commie 7.62x39 would be better than the overdone .223:wall:
And there was a 300 BLK SU-16 in the works that never materialized. I think they had a pseudo-prototype at SHOT one year. I'd like to have a 300 BLK SU-16 and a 300 BLK PLR-16 would be even better IMO. I've given up hoping for an awesome 10mm SUB-2000, but I'm eager to get my hands on the carbine version of the CP33.At one time the RDB-C was being advertised as 6.5 Grendel as well as .223, but I see that isn't on the Keltec web site anymore.
I've heard rumors before that KT planned on making a 308 version of the rdb to replace the RFB but we'll see if that ever happens.