Velocity—The 3-inch version of the Trophy Copper slug has a muzzle velocity (MV) of 2000 fps. With three 50-grain Pyrodex pellets the Barnes 250-grain bullet has an MV of 2197 fps. The slug has 1451 fps remaining at 150 yards and 1305 fps at 200 yards. The muzzleloader, which started with almost 200 fps more than the slug, has 1628 fps remaining at 150 yards and 1467 fps at 200 yards. Slight advantage for the muzzleloader.
Bullet Path—With a 100-yard zero the slug is 3.93 inches below the line of sight at 150 yards and 11.99 inches low at 200 yards. The muzzleloader bullet fares a little better. It’s 3.02 inches below the line of sight at 150 and 9.33 at 200 yards. So, in bullet path, the muzzleloader retains a very slight edge over the slug gun. This is due primarily to the higher velocities.
Energy—The slug has 2,665 ft.-lbs. at the muzzle; 1,744 ft.-lbs. at 100 yards; 1,404 at 150 yards; and 1,135 at 200 yards. The muzzleloader has 2,680 ft.-lbs. at the muzzle; 1,806 ft.-lbs. at 100 yards; 1,472 at 150 yards; and 1,195 at 200 yards. While both retain enough energy to reliably kill a whitetail out to 200 yards, the muzzleloader does have a very slight advantage in energy over the slug—again due to the higher velocities, as energy is tied exponentially to velocity.
Study External Ballistics
Once we go past 200 yards with either of these modern firearms, things start changing very fast. The acceleration of gravity causes the bullet to drop faster and faster as the range increases. The drop below the line of sight for the first 200 yards is more than doubled in the next 50 yards. In other words, relative to line of sight, the bullets drop more from 200 to 250 yards than they did from zero to 200 yards. It just gets worse from there. At 300 yards, the drop is nearly four times as much as it was at 200 yards. Also, by 250 yards both bullets have fallen below the 1,000 ft.-lb. threshold that conventional wisdom holds is the minimum for whitetail deer.
The bottom line is ballistics don’t lie, and they state that for any ethical hunter, 200 yards is about the limit of performance for a modern slug gun or modern muzzleloader. I know that’s not what a lot of hunters believe or have been told, but the facts are the facts. Consistently putting a bullet in the kill zone on a whitetail with either of these guns past 200 yards is going to exceed the abilities of the vast majority of hunters. Once we get a little beyond that, it will exceed the limits of the guns.
The rate of bullet drop is rising exponentially so that even a minor error in range calculation can be critical. The farther the distance to the target, the faster the bullet is dropping so the problem is compounded with every yard of distance added.
Say we have a 6-inch kill zone, which is typical for shooting deer. That means 3 inches in any direction can put you out of the zone. Three inches is how much the shotgun slug drops between 250 and 259 yards. (The muzzleloader is a little better; it takes 18 additional yards past 250 to drop 3 more inches—again, due to the extra velocity from the three-pellet load and lighter bullet.)
So with the shotgun a miscalculation of less than 10 yards can cause you to wound or miss, even if everything else is perfect. But, perfection is impossible. By now the accuracy potential of the guns is starting to grow so large that under field conditions it will be mathematically impossible to ensure a kill zone hit 100 percent of the time. The 2.54-inch group size at 100 yards increases to 6.35 inches at 250 yards, larger than the kill zone. Discounting wind and human error, a 10-yard miscalculation and the simple accuracy of the gun can put the impact off more than 7 inches.
With a mild 10 mph wind the slug has drifted more than 21 inches at 250 yards. A 15 mph wind, just 5 mph more, adds 10.6 inches to that. Can you judge the wind with that kind of precision? I know I can’t. Is it 10 mph or 15 mph? Is it a perfect 90-degree angle or is it more like 45 degrees? Is the wind the same velocity and direction all the way to the target?
If the bullet drifts 32 inches at 90 degrees, how much will it drift if the wind is at 45 degrees? (The answer is 15.2 inches, but I had to go to a computer to figure that out.) So, do you hold 21 inches to the wind or 32 inches or 15 inches? Or maybe you are just trying to shoot too far in this wind?
Even without the wind, it all just falls apart past 200 yards. Use your hunting skill; get closer. That’s the concept of a shotgun or muzzleloader anyway.
Terminal ballistics—what happens after the bullet hits the deer—are much tougher to evaluate. The slug measures .500 inch, which is slightly larger than a muzzleloader bullet at .451 inch, which means the slug has a slightly larger frontal diameter. With a non-expanding bullet the difference might matter. But, they are both expanding bullets. That means the bullet design and impact velocity will control the final frontal diameter. They both expand to a large diameter. This is important for two reasons. One is that with the relatively low velocity of a muzzleloader or shotgun the bullets rely on penetration and frontal diameter to cause tissue damage. The bullet must have enough energy stored to push it through the game in its expanded form. I have shot a lot of deer with monolithic, expanding slugs and muzzleloader bullets. It is rare to recover either from a dead deer. When I do, it is usually from a finishing shot when the deer is down or with an end-to-end frontal shot. With most broadside shots the bullet will exit. So, I can’t see that there is an advantage one way or the other with either of these in deer hunting. Of course, we are looking at only a small representation of the types of muzzleloader bullets or slugs that are on the market. A lead-core, thin-jacket bullet or slug might not exit. However, a total comparison of the terminal ballistics is for another article. For now, I think it’s safe to say that with similar style projectiles, the two are just about dead even for terminal ballistics while hunting whitetails.
I had thought that a clear winner would emerge here, but that’s not the case. I think it boils down to your hunting style, the firearms that interest you most and which one you trust. As a gun guy who loves to experiment, I see that as a half-full glass. On my hunt I can pick a shotgun or muzzleloader with the full confidence that either one is well suited for hunting big whitetail bucks.