KEYMOD or M-LOK?
Lucas Botkin answers the question many people are asking today.
NSWC CRANE Study:
http://www.dtic.mil/ndia/2017/armament/McGee19427.pdf
Firearms used:
Sig Sauer MCX
BCM 13.7
BCM 14.5
BCM 11.5
ADM UIC 2
FNH SCAR 17 (13.7 length)
Daniel Defense 5V1
SOURCE