MDT M-LOK Spare Round Holder

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MDT M-LOK SPARE ROUND HOLDER
Two spare cartridges defined on the system instead of loose in the pocket
Reversible cartridge holder with small and large holder body, adjustable retention, and M-LOK/ACC mounting method.
2 cartridges · M-LOK / ACC
Black-Raptor classification This is not a magazine and not a capacity extension. The holder makes sense if exactly two cartridges should always be accessible in a trained sequence at the same place and interface, caliber body, and operating side fit cleanly.

Does this fit your plan?


Fits well if …
you have a suitable M-LOK surface or the ACC mounts provided by MDT
two spare cartridges are deliberately guided on the system
you want to adjust retention and mounting side to your cartridge and hand



Fits less if …
you want to organize more ammunition or replace a magazine
no confirmed mounting surface is available
you use .338 Lapua Magnum – MDT explicitly states no fit for this



Practical use


Left or right The assembly is reversible. The sensible side depends on the access hand, ejection port, and other accessories.


Adjustable retention Washers and O-rings allow adjusting the holding force to the cartridge used.


Two caliber bodies Small and large holder bodies cover different cartridge families without claiming universal fit.


Limits, disadvantages, and avoiding bad purchases
MDT names .223, 300 AAC, .224 Valkyrie, 7.62×39, and 6.5 Grendel for the small body; .308, 6.5 Creedmoor, .450 Bushmaster, 7 mm, .300 WM, .300 PRC, and 6.5 PRC for the large body. According to existing MDT, .338 Lapua Magnum does not fit
-No information. Do not infer other cartridges from similarity.
Technical data with practical consequences


Capacity 2 reserve cartridges – no magazine.


Mounting M-LOK or the side ACC accessory mounts described by MDT.


Side selection Reversible left/right – check operating path on unloaded system.


Material Glass fiber reinforced polypropylene according to MDT.


Retention Spacer system with washers and O-rings.


Tool 1/8-inch hex key according to existing instructions.


Mounting and safe use
Before mounting, fully unload the firearm, remove magazine and bolt. For M-LOK, the T-nuts on the inside must rotate correctly and lock. Adjust retention only with loose cartridges and set so they are held securely but can be removed in a controlled manner.
Scope of delivery
Small and large polymer holder body, spacer system with washers and O-rings, as well as the M-LOK mounting kit with interface plate, screws and M-LOK nuts described in the existing MDT instructions.
Frequently asked questions
How many cartridges does the holder take? Two. Does it fit left and right? Yes, the design is reversible. Does .338 Lapua Magnum fit? No, MDT does not specify fit for that. How do I adjust the retention force? Via the appropriate holder body and washers/O-rings according to the existing MDT configuration. Is this a magazine? No. It is only a holder for two loose reserve cartridges. Clear purchase decision
Good for a deliberately organized precision setup with confirmed counterpart and matching cartridge family. Wrong if you actually want to organize magazine or ammunition capacity.