NEWS | July 29, 2021

Strykers: Maintaining the Mortar Carrier Vehicle’s RMS6-L

Crewmen, your M1129A1 MCV, M1251A1 MCVV and M1252 MCVV Stryker’s RMS6-L 120mm mortar system needs a lot of attention to stay combat ready. Keep the following Do’s and Don’ts in mind so that your mortar does its job:
  • Maintain gun card accuracy on DA Form 2408-4, Weapons Record Data Card.
Maintain gun card accuracy
Maintain gun card accuracy on DA Form 2408-4
  • Follow operator and maintenance service/inspection intervals as outlined in TM 9-2355-311-13&P (Sep 16), TM 9-2355-363-13&P (Sep 16) and TM 9-1000-202-14 (Feb 99, w/Ch 8, Feb 19).
  • Forecast service parts that are needed to maintain the RMS6-L and keep them in stock.
  • Remove mortar tubes to clean and lube them to help prevent cannon tubes from seizing in the sleeve.
  • Establish a unit SOP to remove and store cannon tubes in the arms room.
  • Only mount a tube in its assigned/paired vehicle.
  • Keep track of dates so you know when the magnetic particle inspections (MPI) are due. Make sure you:
    1. Implement GCSS-Army measures to track MPI dates
    2. Inspect six (6) months prior to MPI due date.
    3. Stagger MPI inspections to offset shortages in the supply system.
Keep track of MPI dates
Keep track of MPI dates
  • Use TMs during command maintenance.
  • Complete all pre-firing checks.
  • Follow the inspection and condemnation criteria found in Appendix V of TM 9-1000-202-14.
  • Maintain the M3 borescope kit. Be sure to use the right light bulbs and have good replacement bulbs. Note the following NSNs for lamp incandescent bulbs:
    • NSN 6240-00-295-0907
    • NSN 6240-00-922-7915
    • NSN 6240-00-155-7866
    • NSN 6240-00-092-3186
  • Properly install staffs when connecting the M3 borescope.
  • Install the retaining band with the clamp bolt at approximately the six o’clock position (facing down).  
Install retaining band with clamp bolt at 6 o'clock position
Install retaining band with clamp bolt at 6 o'clock position
  • Have missing or incomplete record information on gun cards (round count, borescope and pullover expiration and MPI date expiration)
  • Fail to follow the TMDE calibration standards for special tools and test equipment (STTE).
  • Improperly use and store STTE.
  • Misplace TMs.
  • Fail to conduct PMCS as outlined in TM 9-2355-311-13&P, TM 9-2355-363-13&P and TM 9-1000-202-14.
  • Bypass pre-firing safety confirmation checks.
  • Allow overdue service dates for the RMS6-L.
  • Fail to follow pull-back exercise intervals.
  • Fail to follow bleeding procedures on M3 pump, replenisher, recuperator and recoil system.
  • Ignore proper bench bleeding procedures during recuperator installation.
  • Forget to order pushing screw and nitrogen adapter for recuperator maintenance.
  • But do make a note of the following NSNs:
    • NSN 3040-00-929-4632, pushing screw
    • NSN 4720-01-633-7354, nitrogen adapter
  • Forget to requisition RMS6-L service parts prior to service dates.
  • Mishandle basic issue items (BII), causing equipment damage on the RMS6-L.
  • Have an unserviceable M3 borescope.
  • Use the wrong light bulbs and damage pins and sockets on the M3 borescope.