CMMG .350 Legend 10-Round Magazine

.350 Legend is a straight-walled cartridge designed by Winchester in 2019 specifically to be legal in midwest deer states that prohibit bottlenecked rifle cartridges. The straight-wall geometry will not feed from any standard 5.56 PMAG, Grendel mag, or .300 Blackout mag. CMMG's dedicated .350 Legend magazine is the standard option for the cartridge.

The 10-round capacity is the practical limit for the cartridge in a standard AR-15 magazine well, set by the bullet length and straight case profile. The polymer body uses an internal geometry tuned for the .357-diameter bullet and the cartridge's straight-wall case. This is the same magazine that ships from the factory with the CMMG Resolute Mk4 .350 Legend rifle and most other major .350 Legend AR-15s.

For deer hunters in Iowa, Ohio, Michigan, Indiana, and parts of Pennsylvania where .350 Legend is the legal answer to bottleneck-cartridge bans, buy at least two or three of these. PSA also makes a similar magazine; the CMMG version generally ships with better fit and finish.