Sig Sauer Introduces Copperhead MPX Pistol Gun News Guns January 14, 2019January 15, 2019C. BaileyLeave a Comment on Sig Sauer Introduces Copperhead MPX Pistol New for 2019. The Sig Copperhead in 9mm. I can honestly say I would love to shoot it. Read more at Shooting Illustrated Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)