SKU: BPAA40BUFKIT
UPC: 853427007271
MPN: AA40BUFKIT
The Angstadt Arms 10 oz AR-15 Buffer Kit is an extra-heavy buffer system built for blowback-operated pistol-caliber carbines chambered in 9mm Luger, .40 S&W, and .45 ACP. At 10 ounces, this is the heaviest buffer in the Angstadt lineup, and it exists to slow the bolt during the violent cycling that blowback PCC actions generate. Shooters running suppressed builds or anyone fighting excess bolt speed, muzzle rise, and ejection problems will get the most out of it. The kit ships complete with everything needed to drop it into a standard carbine-length receiver extension and start running.
This is a full kit, not just a buffer. Angstadt Arms includes the 10 oz buffer, a carbine buffer spring, and a spacer so the assembly seats correctly in a standard carbine receiver extension. The buffer measures 4 inches in length and carries a black finish. It functions with both GLOCK and Colt-pattern magazine builds, which covers nearly every AR9 lower on the market. The added mass is the whole point: a heavier buffer keeps the bolt closed longer, smoothing out the cycling that lighter rifle and carbine buffers can't handle in straight blowback designs. If you've been running a lighter buffer like a 8 oz Angstadt kit and still see brass thrown hard or a snappy recoil pulse, the extra weight here addresses it directly.
Reach for this buffer when you're tuning a blowback PCC for softer recoil or building a dedicated suppressor host, where the heavier mass helps tame the increased back pressure a can adds to the system. It drops into a standard carbine-length tube, so no proprietary hardware is required. If you're sourcing the rest of the build, browse our lighter Angstadt PCC buffer options for comparison, or look at our other heavy 9mm buffers and carbine receiver extension kits to complete the lower. Backed by a 14-day worry-free return window on non-serialized parts.
The added mass slows the bolt during blowback cycling, keeping the chamber closed longer. That reduces bolt speed, softens the recoil pulse, and helps control violent ejection. In a 9mm, .40, or .45 AR build, the extra weight smooths out function that lighter carbine and rifle buffers struggle to manage in straight blowback systems.
Yes. The kit includes a spacer so the 10 oz buffer and carbine spring seat correctly in a standard carbine-length receiver extension. No proprietary tube or hardware is required to install it.
It's optimized for suppressor use. A can adds back pressure to a blowback action, which increases bolt speed. The heavier 10 oz mass counteracts that, keeping the action under control when you run a suppressor on your 9mm, .40, or .45 build.
Yes. Angstadt Arms specifies compatibility with both GLOCK-style and Colt-style magazine builds, covering nearly every AR9 lower configuration available.
The kit includes the 10 oz buffer, a carbine buffer spring, and a spacer. That's everything needed to set up the buffer assembly in a standard carbine receiver extension.
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Angstadt Arms
Angstadt Arms
Angstadt Arms