3 1/2 Magnum shells

[charlie cleveland]

assuming youre talking about 12 ga 3 1/2 inch mag shells..you canusally punch in the powder you wanta use and the makers of the poder will haverecipes for their powder..just pick a powder makers name and try it...also the thing i did was buy a shotgun shell reloading manual they have plenty of 3 1/2 inch loading material...charlie

[J. A. EARLY]

MEC 3 1/2" conversion kit.

Precision Reloading has them.

Different models for loaders with primer tray and those without.

$71.29 without tray in my 2014 catalog. $90.99 with primer tray kit.

Of course you can get directly from MEC.