20MM Automatic Cannon Rounds With Links


I need help identifying these two 20mm rounds. The longer 20mm round has an overall length of 7-1/16" with a case length of slightly more than 4-5/16". The primer pocket is red. The case head is marked 20MM MK5. MOD. 0. RNO.7.66. The driving band is marked 20MM MK-11-1 [A] CL11-67-3. The shorter 20mm round has an overall length of 6-5/8" with a case length of 4" and contains what appears to be a primer. There are no markings. The links are marked BLM-6-10 over 6 M14A2. Are the links correct for either or both rounds?


The shorter one is the 20x102 M56 and the longer one is the 20x110 USN (navy).

The links are the M14A2 and are used for the 20x102 only.

The links for the 20x110 USN look similar but the lower clamp section is a bit longer.