This DBM Allows you to run AI 308 or 223 mags in your Winchester Long Action Mod 70 Rifle. For Years Winchester made Long action rifles in short action calibers, and this allows the use of a AI Box Mag. Install is required, and we can provide inletting and install services as well. Installs are free at CDiPrecision, so click Install option and send your rifle in for install. Easy and fast. 3 week turnaround or faster. US Addresses only. Mags Must be purchased Separately.