Spike's Tactical St-9x 9mm Heavy Buffer
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Spike's Tactical
Overview
The Spike's Tactical ST-9x 9mm Heavy Buffer is a robust component designed specifically for use in AR-15 builds that utilize a Mil-Spec Carbine buffer tube. Constructed from stainless steel, this buffer is engineered to enhance the cycling of 9mm rounds, providing stability and reliability during operation. While it is tailored for 9mm configurations, you'll commonly find this buffer in builds featuring a mid-length gas system, particularly those chambered in 5.56 NATO.
Specifications
Available Merchants(8)
Prices checked
Price Alert
September 2026 on GunPartPicker
Spike's Tactical St-9x 9mm Heavy Buffer ranked #41 of the 86 buffers builders added on GunPartPicker in September 2026. Builders have been adding it to their builds on GunPartPicker since February 2026. All time, it ranks #35 of the 193 buffers builders have added. Builds with this buffer are split between 5.56 NATO (47%) and .308 Win (20%), mostly on mid-length gas (71%, then carbine-length 29%), and mostly AR-15 (71%, then AR-10 17%).
Availability is good: it was in stock at one retailer or another nearly every day in September 2026, but today 2 of the 8 retailers we track have it in stock. Prices barely moved in September 2026, holding around $44.96, so there haven't been real sales lately. Buying today, the lowest price is $44.96 at Primary Arms, which matches the best price we saw in September.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
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Frequently Built With
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Strike Industries AR Carbine Flat Wire Spring
Build Configuration Breakdown
Aggregated and anonymized data showing how builders use this product
PlatformBased on real build data showing which platform (AR-15, AR-10, AR-9) builders pair with this product.
CaliberBased on real build data showing which calibers builders choose alongside this product.
Gas SystemBased on real build data showing which gas system lengths builders use with this product.
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