Quote:
The 3" shotshell wasn't introduced until 1923 and in only some heavily constructed heavy waterfowl guns.

This was the introduction of what we know today as the "Magnum" loading. 3" shells existed from back in the 1800's but they were not loaded particularly heavier. They had allowed for a better wad column with bulky powders such as either Black or Bulk Smokeless, both of which were the most commonly reloaded powders. About the maximum load for the day was 3Ľ to 3˝ drams or equivalent powder with 1Ľoz shot.

Miller/TN
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