Dirty Bird MCF-A Ambidextrous Lower Receiver
Dirty Bird Industries Multi-Cal Forged Ambidextrous (MCF-A) Lower Receiver
Built for shooters who demand reliability, innovation, and quality, the Dirty Bird MCF-A Lower Receiver stands as a class-leading option for any AR builder.
Precision-Crafted from the Finest Forgings
Our MCF-A lowers are meticulously machined from top-tier 7075 Aluminum forgings.
Manufactured by VKTR Industries: Innovation Meets Attention to Detail
Dirty Bird has partnered with VKTR Industries, renowned for their engineering excellence and commitment to premium quality. VKTR’s dedication to advanced machining and tight tolerances ensures each MCF-A lower meets the highest standards and delivers outstanding performance you can trust.
Enhanced Practical Features
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Ambidextrous Bolt Catch/Release: The MCF-A’s innovative mechanism provides seamless ambidextrous operation—release or lock the bolt back with ease from either side of the receiver. Designed for durability, the system functions independently of the standard bolt catch in case of damage or debris.
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Simplicity & Serviceability:Â With only 4 proprietary components (all crafted from Billet S7 Tool Steel and QPQ Nitrided for unbeatable strength), there are zero hex screws. The ambi bolt catch lever uses a standard bolt-catch roll pin for straightforward maintenance and high reliability.
Made in the USA & Lifetime Warranty
Proudly manufactured in the USA, the MCF-A Lower Receiver is protected by Dirty Bird’s Limited Lifetime Warranty, ensuring your investment is backed by our commitment to quality.
| Weight | 0.0000 oz |
|---|---|
| Color | Black, FDE, Midnight Bronze, OD Green, Sniper Grey |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
Customer Reviews
- Reviews
- Questions
- buffer tube
- LWRC
- military gauges
- side bolt catch / release
- TRIGGER
- grade
- chatter
- nicest receivers
- vibratite
- tolerances
US
It passed SOTAR save for one minor issue
Took this to SOTAR for his class and everything passed with flying colors save for the buffer tube threads which were a class 1 (lowest grade), but with FCD buffer tube, class 2, and A5 barrel nut, class 3 with some vibratite we got it to around a 2 - 2.5 class. The magwell had no issues with military gauges either. The ambi controls are unique and I like them over other offerings like ADM, Radian, etc. The right side bolt catch / release does take a little effort to use, but if fine otherwise.
USAnti-rattle pin included
There is little mention of the spring loaded pin near the buffer tube that applies pressure to the upper receiver, effectively removing the chatter between the upper and lower receiver. The Dirty Bird lower is the only receiver I've seen that includes it in their product. Bravo! This makes the Dirty Bird Lower Receiver one of the nicest receivers on the market.
USDirty Bird Ambi Lower
Very impressed with this lower! I have tried most of the ambi lowers (Radian, LMT, Aero, American Defense and a few others) While a couple of the name brand lowers might be a little more robust. I feel like the Dirty Bird is the most intuitive option. The bolt catch/release is the same mechanical action. Some of the other brands use a different lever/button for the bolt catch and/or release or are not truly ambi with NO right-side bolt catch, buy with confidence!
USHidden gem
As someone who’s either owned or tried all the mainstream ambi lowers (adac, adm, LMT, LWRC, etc) this is not only the most effective but also maintains the compatibility and strength of a regular forged lower.
USIf the only bird you know about is a duck... you're missing out!
Not only did I get the lower, picked up the upper, bcg, handguard, trigger... this was a great build and the tolerances are fantastic! I've built over 30 and this went together as easily as noveske and solgw with no additional machining or lapping required.
