Glock 31 Magazine Features This Glock factory magazine is built specifically for the Glock 31 in .357 Sig holding 10 rounds in a durable black polymer body that matches the pistol s factory fit and finish exactly. Because it is a genuine Glock component it drops in and functions identically to the magazine that shipped with the pistol with no adjustment required. The polymer housing resists the dents and corrosion that can affect metal-bodied magazines making it a low-maintenance option for range use or daily carry. Reliable feeding from a Glock magazine depends on precise dimensional tolerances and this factory magazine is manufactured to that same standard. Glock notes that its magazines can be difficult to load fully when new and that the last round may not seat easily until the magazine has gone through a break-in period. Loading the magazine with all but the final round and letting it sit for a few days helps compress the spring and ease this process. Cycling the magazine from full to empty several times can also speed up break-in. This Glock 31 magazine is available for sale at GrabAGun for owners who want a genuine factory spare or replacement in .357 Sig. Glock 31 Magazine Specifications Manufacturer: Glock Compatible Hosts: Glock 31 Caliber: .357 Sig Capacity: 10 Rounds Color: Black Material: Polymer Available At: GrabAGun