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FDF-15 Manual


While FDF-15 is built for reliability, doing your part is key. The number one reason for the malfunction of gas-operated rifles is the lack of lubrication. Proper lubrication means keeping the upper receiver raceway and bolt carrier group (BCG) looking “wet". FDF-15 will run perfectly fine dirty, but not dry.


Bolt Carrier Group:

FDF-15's BCG is manufactured with many high-quality, upgraded components, such as extra-power ejector and extractor springs, OCKS (optimized carrier key screws), ball staking, and most important to note during maintenance: a directionally-marked cam pin. When disassembling the BCG for maintenance, you will notice that the cam pin is marked with a chevron. This is to indicate the direction in which the cam pin should be reinstalled. It is important to always install the cam pin in the same direction to limit wear to the cam pin itself, and also the mating bolt tail. Limiting this wear will extend the life of those two interfacing parts.



Keep it simple! Wipe out the upper, wipe off the BCG, add more oil. We recommend the use of high quality, synthetic-base lubricant. Here at First Due Firearms, we use Slip2000 during the assembly process, and on our personal own rifles. This lubricant is also available to purchase at First Due Firearms.

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