In the thirty or so years before the introduction of the 12-gauge, 3-inch, progressive burning smokeless powder, high velocity, 1 3/8-ounce loads, the heaviest 12-gauge loads offered by our North American ammo companies were 3 1/2 drams of bulk smokeless powder or 28-grains of dense smokeless powder such as Infallible or Ballistite pushing 1 1/4-ounce of shot. These loads were offered in 2 3/4-inch and longer shells. The perceived advantage of the longer shells was more/better wadding.

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Customers didn't always order the heaviest possible loads in their long shells --

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