For the past 50 years, I have always had some type of 12 gauge shotgun. My first shotgun was a 12 gauge Mossberg 500 pump. My grandfather was hesitant to purchase this for me—I was 12 or so at the time—as he had used proven Winchester and Remington types. However, I liked the looks of the Mossberg and the rest is history. Today, I own and use several makes, but Mossberg shotguns are still on the front line.
I began using field loads for hunting birds, rabbit, and squirrel. I never fired buckshot until I became a peace officer. While the few instances in which the shotgun was used by my agency were impressive, I did not give the shotgun slug much thought until I entered service in a mountain region.
Buckshot was fine for municipal agencies but practically worthless past 20 yards in standard service grade shotguns. I began testing shotgun slugs. I found most of the slugs available would group five shots into five inches at 50 yards with the Remington 870 issued by the agency. That was OK for most uses. I also kept a .30-30 lever action rifle in the trunk.
Recently, I have become more interested in shotgun slug performance. There are many highly developed slugs and rifled barrel shotguns. I elected to test shotgun slugs in a rifled shotgun barrel and compare it to a standard shotgun barrel. I had two goals. First, the test wasn’t fair as one of the shotguns featured an optical sight and the other a simple bead. On the other hand, I did discover how useful a slug would be in a general use defensive shotgun, and also how accurate the slug could be in a rifled barrel.
I chose three proven slugs loads. Fiocchi’s Aero slug is a long time favorite. Here are the loads tested: Fiocchi 1 ounce, 1,150 fps slug, Fiocchi 7/8th ounce 1,300 fps slug, and the 1 ounce 1,560 fps blockbuster. As may be expected, most of the work was done with the reduced recoil 1,150 fps load. The test shotguns were a Mossberg 590 with 20-inch barrel, my front line shotgun, and a new acquisition, a Mossberg 500A with rifled barrel and 3×9 scope.
There are a number of tips and concerns when testing rifle slug accuracy from a benchrest. The shotgun rises in recoil, no question there. The forend must be stabilized against recoil. Yet, there must be some give or the scope may be wrecked from pounding. If you fire a group that is well centered and the following hits are high, then you are flinching and losing control of the shotgun. That is the hard part.
A three-shot group shows the accuracy of the shotgun and slug combination while a five-shot group reflects the shooters potential. I began firing for accuracy with the Mossberg 590. I fired the reduced recoil slug at 25 yards. A three-shot group of 1.4 inch was encouraging. This is more than adequate for personal defense and a great choice for those ranges when buckshot has spread to the point that it is no longer effective.
Firing from a solid braced standing barricade at 50 yards with a bead front sight, the groups ran around five inches. This slug isn’t difficult to manage and makes a fine choice for those situations in which increased penetration is desirable. However, reduced-recoil slugs may print up to 4 inches below the point of aim, as they are not as speedy as full power loads and drop must be considered. The 7/8-ounce 1,300 fps load was fired at 50 yards. This load generated more thump and was closer to the point of aim. Groups were similar with this loading.
Next, I moved to the scoped Mossberg shotgun. This slick and nicely engraved Mossberg is an outdoors piece. It is highly specialized and isn’t useful for anything save firing slugs. (Do not fire standard shot in a rifled barrel- the pattern if any will be like a doughnut and may even be dangerous to those to one side of the shotgun.) I elected to skip the 25-yard testing and go straight to the 50-yard test.
I had previously sighted the shotgun in for the reduced-recoil slug, so this wasn’t an impediment in the testing. The Fiocchi reduced-recoil load put three slugs into two inches. This Mossberg trigger is OK to fair, and I felt that if I had not been attempting to manage this trigger I would have had a better group.
The full power 1,300 fps load did a little better at 1.6 inches. This is certainly a good choice for the type of woods hunting slugs are generally used for. Moving to the heavy loaded slug I was glad to have a thick recoil pad on hand. The results were excellent. While this load struck several inches higher than the 1,300 fps load at 50 yards, it would have been simple to sight the Mossberg in for this loading. Accuracy was the best of the test with a 1.3-inch group at 50 yards. These slugs burn clean and provide an excellent option for those hunting with solid shot.