3.5" Short Buffer System

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Micro Conversion Kits

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AR Build Kits

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Micro
Conversion
Kits

Full Rapide line up, how could you choose just one?

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Anodized Parts

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Skeletonized Parts

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MCK Accessories

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BEST SELLING ACCESSORIES

AR-15 5.56 NATO 5'' PISTOL KIT - FORGED UPPER WITH 4'' M LOK RAIL - INCLUDED BLUE BCG

MSRP: $509.99

$415.99

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Short Buffer Tube System With QR Sling Adapter Cap - Black

MSRP: $99.99

Was: $75.99

Now: $69.99

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5" 5.56 NATO UPPER ASSEMBLY (BUILT)

MSRP: $335.99

Was: $325.99

Now: $289.99

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MCK GEN 2 | MICRO CONVERSION KIT GEN 2.0 Glock 17/ 19/ 19X/ 22/ 23/ 31/ 32/ 45

MSRP: $399.99

Was: $289.99

Now: $265.99

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AR PARTS
AND
ACCESSORIES

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Low Cost AR-15 Parts

If you’re looking for Low cost AR-15 Parts and Kits, you’ve come to the right place. We are constantly doing promotions and we also try to keep our deals section stocked up with excellent deals on the AR-15 build parts you’re looking for.

Recent Blogs

Most Popular Short Barrel Rifle Upper Finishes Read More

Cerakoted Parts in Assembled Uppers: The Advantages of Cerakote Read More

Assembled Upper Parts, and How They Affect Performance Read More

Two Great CAA MCK Accessories for Intermediate Range Shooting Read More

Welcome to MCS! The builder’s choice for Deals on AR-15 Parts, Micro Conversion Kits, Accessories and more. All competitively priced and backed by outstanding customer service.

Micro
Conversion
Kits

Full Rapide line up, how could you choose just one?

Anodized Parts

Skeletonized Parts

MCK Accessories

BEST SELLING ACCESSORIES

Featured Products

AR-15 5.56 NATO 5'' PISTOL KIT - FORGED UPPER WITH 4'' M LOK RAIL - INCLUDED BLUE BCG

Short Buffer Tube System With QR Sling Adapter Cap - Black

5" 5.56 NATO UPPER ASSEMBLY (BUILT)

MCK GEN 2 | MICRO CONVERSION KIT GEN 2.0 Glock 17/ 19/ 19X/ 22/ 23/ 31/ 32/ 45

AR PARTS
AND
ACCESSORIES

Low Cost AR-15 Parts

If you’re looking for Low cost AR-15 Parts and Kits, you’ve come to the right place. We are constantly doing promotions and we also try to keep our deals section stocked up with excellent deals on the AR-15 build parts you’re looking for.

Recent Blogs

Welcome to MCS! The builder’s choice for Deals on AR-15 Parts, Micro Conversion Kits, Accessories and more. All competitively priced and backed by outstanding customer service.

Micro Conversion Kits

Full Rapide line up, how could you choose just one?

Anodized Parts

Skeletonized Parts

MCK Accessories

BEST SELLING ACCESSORIES

Featured Products

AR-15 5.56 NATO 5'' PISTOL KIT - FORGED UPPER WITH 4'' M LOK RAIL - INCLUDED BLUE BCG

Short Buffer Tube System With QR Sling Adapter Cap - Black

5" 5.56 NATO UPPER ASSEMBLY (BUILT)

MCK GEN 2 | MICRO CONVERSION KIT GEN 2.0 Glock 17/ 19/ 19X/ 22/ 23/ 31/ 32/ 45

AR PARTS AND ACCESSORIES

Low Cost AR-15 Parts

If you’re looking for Low cost AR-15 Parts and Kits, you’ve come to the right place. We are constantly doing promotions and we also try to keep our deals section stocked up with excellent deals on the AR-15 build parts you’re looking for.

Recent Blogs

Micro
Conversion
Kits

AR PARTS
AND
ACCESSORIES