NSWC Crane Recommends MLOK to SOCOM

Soldier Systems Daily reported late last night that Naval Surface Warfare Center Crane has conducted testing of multiple modular rail systems and after testing NSWC Crane recommended SOCOM adopt Magpul’s MLOK for acquisition efforts.


The full report and testing results are not yet cleared for public release, but the executive summary has been released to the public.


A few things in this EXSUM stuck out to me.

The EXSUM mentions “other modular rail systems” (plural) so aside from KeyMod – which is an assumption on my part, I’d like to know what other types of mounting systems were tested.¬† But I have my doubts that any of those lesser known attachment methods would have been recommended to SOCOM without demonstrating a clear superiority to MLOK and KeyMod. The lesser known attachment methods might have not have a chance of being the NSWC Crane’s recommendation to SOCOM due to an inability to solicit a Request for Proposal (RFP) that could be answered by multiple NAICS code holders. SquareDrop,¬†SIGMOD, HKey, KeySlot, Qsert, and RAHG (among others) have very little traction outside of their creator companies championing those methods. If an RFP for a SIGMOD rail could only be answered by Sig Sauer, then only one entity could answer that RFP.


KeyMod and MLOK are the two major competing industry standards for modular rail attachment in the commercial AR15 world. (image from ar15news.com)

In repeatability testing, M-LOK allowed for the repeated installation of the same accessory rail in the same location on a handguard with an average point of aim (POA) shift of 1.3 MOA, as low as one quarter the average POA shift observed by other modular rail systems.
– Did MLOK perform the best in this, or was the worst performer just 4x worse than MLOK? If MLOK did not perform the best, what attachment method did perform the best for repeatability testing?

Drop test results demonstrated that M-LOK systems maintain securement of accessories to the handguard and sustain less damage from impact forces than some other modular rail systems.
– Notice it said “some” and not all. What system or systems outperformed MLOK in this test?

Failure load testing demonstrated that M-LOK systems support the highest load of all modular rail systems tested. In fact, the test equipment used to interface with 1913 accessory rails secured with the respective modular rail system across testing repeatedly failed prior to failure of the M-LOK attachment system. Even so, testing of the M-LOK systems failed at loads as high as over three times the maximum failure load of some other modular rail systems.
– Ok, so this was a tested area where MLOK was the top performer. Again, knowing where the other systems failed would help to see if MLOK only performed marginally better than KeyMod and that 3x margin of superiority MLOK showed was over one of the more obscure attachment methods then it doesn’t really indicate the death of KeyMod.

That being said, SOCOM does have an impact on commercial industry standards.

The MLOK:KeyMod ratio in my safe is 4:1; I’d just like to know the full test data to understand SOCOM’s decision. In the EXSUM it appears that only 3 of the 5 tested areas identified a wide performance variance among the tested systems and of those 3 area only one area was mentioned where MLOK was the top performer. Knowing these test results would help drive innovation in the commercial market and in Department of Defense small arms development.