This Foxtrot Mike 9mm Glock style Builders essentials kit, includes the key components to have a reliable 9mm P.C.C. Each kit contains a complete Premium FM9 Bolt Carrier Group BCG, .308 Carbine Recoil Spring and a Heavy Buffer to ensure proper function on your 9MM Glock Style P.C.C. Build. The 6.4oz Heavy Buffer is the perfect weight to ensure reliable feeding of any blow-back operated P.C.C. 3.7 inch overall length, requires no spacer and helps prevent bolt catch breakage. Smoother function, less felt recoil, and reduced rate of fire from your AR pistol. The FM-9 Heavy Buffer Kit is compatible with all 9mm upper receivers FM Products uses a Premium .308 Carbine Recoil Spring to soak up the recoil impulse created by Blow Back platforms. The extra heavy duty recoil spring helps with feeding and reliability, and is critical to reliable function of a 9mm Blow Back gun. Specifications for FM Products 9mm Bolt Carrier and Heavy Buffer: Manufacturer: FM Products Color: Black Finish: Salt bath Nitride Melonite/QPQ Fabric/Material: 4340 Steel Cartridge: 9mm Luger Gun Make: AR Platform Gun Model: AR-15 Additional Features: .308 Carbine Recoil Spring Included Accessories: S7 Tool Steel Extractor and S7 Tool Steel Firing Pin coated in Nickel Boron Condition: New Weight: 6.4 oz, 6.5 oz Muzzle Device: Micro Blast Diffuser Features of FM Products Glock Style 9mm Builders Essentials Kit Compatible with all blow-back 9mm upper receivers; Salt bath Nitride Melonite/QPQ finish gives lubricity and wear-resistance; Heavy 6.4 oz. (pistol) weight; Kit comes with a .308 Carbine Recoil Spring to ensure proper function of your 9mm P.C.C. Build; Premium 4340 Steel Bolt Carrier, machined pre hardened; S7 Tool Steel Extractor; S7 Tool Steel Firing Pin coated in Nickel Boron; Deep Black Melonite finish gives lubricity and wear-resistance; Removable weight, compatible with all PDW stocks and Captured Recoil Systems on the market; Ramped to accommodate both MIL-SPEC and 9mm hammers; Premium Chrome plated firing pin; Forged, then precision machined extractor made from S7 tool steel; M16 profile; Manufactured with ISO:9001 and AS:9100 quality certifications; Premium one piece design, much stronger than 2 piece BCG on the market; Extractor spring and Hardware made to Colt Spec Package Contents: FM Products 9mm Bolt Carrier and Heavy Buffer
Dave –
I was pleasantly surprised to see that when I could not get just the FM9 BCG, I was able to, for the same price, get the same BCG but WITH a solid steel buffer and 308 flat wound spring, made for AR9 builds. I've built several AR9's over the years and all but one was with the FM9. They run smooth, seem to be tough, and have a great look via the shell ejection port.
Haunted Bliss –
Bcg had same issue as another review where spring pin wasn't flush and was mushroomed. Didn't affect function. Cycles fine with endomag without scraping mag. 308 spring had issue with charging and clearance. Very hard to pull charging handle. Used buffer and regular AR-15 spring and no issues at all. It works so overall worth it.