Sig Sauer
Overview
The SIG Sauer M400 SIG ROMEO5 5.56 NATO 16" - AR-15 Rifle is a optic. Compare prices from multiple merchants and find the best deal.
Specifications
Available Merchants(1)
Prices checked
Price Alert
Build history on GunPartPicker
Builders on GunPartPicker first added the SIG Sauer M400 SIG ROMEO5 5.56 NATO 16" - AR-15 Rifle to a build in May 2026.
Availability is good: it was in stock at one retailer or another nearly every day in September 2026, and today the one retailer we track has it in stock. Prices barely moved in September 2026, holding around $1,399.99, so there haven't been real sales lately. Buying today, the lowest price is $1,399.99 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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