What is magnum? (12 gauge)

[Wrenches]

Ok so I was looking at the boxes of Remington 12 gauge OOO bucks.

Buckshot 12 2 3/4 1325 8 OOOBK

Buckshot 12 3 1225 10 OOOK (magnum)

Now the velocity difference (faster in 2 3/4) got me thinking, does magnum refer to the powder or the no of pellets?

 

[GunnyGene]

Both. The higher pellet count (weight) requires additional powder charge to keep velocity reasonable without going over pressure limits, which is why velocity is lower than a 2 3/4" shell. Plus the length to accommodate the extra pellets and powder. Some of it is just marketing, but most 3" will be called magnums.

Something to pay attention to from: http://www.chuckhawks.com/12gauge.htm

12 gauge Magnum shells are even worse. A 2 3/4 inch Magnum shell throwing 1 1/2 ounces of shot at 1260 fps from a 7.5 pound shotgun belts the shooter with 45.9 ft. lbs. of recoil, somewhat more than the recoil of a typical .375 H&H Magnum rifle shooting 300 grain factory loads! And the 3 inch Magnum 12 gauge shell firing 1 7/8 ounces of shot at a MV of 1210 fps in that same 7.5 pound shotgun slams the shooter with over 60 ft. lbs. of recoil energy. This is equivalent to the recoil of a .378 Weatherby Magnum rifle, and exceeds the recoil of a typical .458 Winchester Magnum rifle. This is literally recoil in the elephant gun class, and most shooters would be well advised to avoid such loads.

 

[Wrenches]

Thanks Gunny, that was a good read. I clicked home and BMed it.