The only two companies that I know contracted for Sears and made ammo would be Winchester or Savage But it could have been any manufacture. Since it says Sears on the head stamp it would seem they made alot of the ammo for Sears. But i'm tapped I don't know . Such as it is I hope this helps.
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" Without proper weaponry the hunter will become the hunted"
It has mine up to. Sears always sold guns from other manufactures under a name common to them. I have a J.C. Higgins .22 that was sold by Sears and Robuck I believe it was made by High Standard. I also have a box of Montgomery Wards high speed 22 long rifle shells made by Federal. WHO WOULD HAVE THUNK IT.
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" Without proper weaponry the hunter will become the hunted"