It’s hard to beat a Remington 870 for reliability in almost any conditions. A Remington 870 also likes to beat the taste right out of your mouth when it comes to recoil, especially when you’re shooting full-power slug and buckshot loads.
It all comes down to physics. The thump you feel when you pull the trigger is a direct result of the mass of stuff coming out the front end (projectiles and powder charge) and the velocity with which all that junk exits the fiery end. If you’re going to launch something like a one-ounce shotgun slug at 1,600 feet per second, you’re going to feel it on your shoulder and face. To put that in common handgun and rifle load perspective, a one-ounce slug is equivalent to a 437.5-grain bullet. So, using round numbers, a .45 ACP uses a bullet about half that weight and fires it at about half that velocity. And that doesn’t even count the much heavier powder charge in the 12-gauge shell which contributes to recoil too.
Let’s take it one level deeper. That “standard” .45 ACP load generates about 5.34 foot-pounds of recoil energy when fired from a Smith & Wesson SW1911 TA. As recoil energy also depends on the weight of the gun, I’ll note that this particular model weighs 41.7 ounces empty.
If we consider a Remington 870, say the Express Synthetic Stock Tactical Model, which weighs 7.5 pounds, it generates 23.66 foot-pounds of recoil energy when firing that one-ounce slug at 1,600 feet per second. A 1-1/8 ounce 00 buckshot load moving at 1,450 feet per second generates about the same. That’s almost five times as much recoil energy as the 1911 load.
But recoil energy is only part of what you feel. Another important factor is the time duration of the recoil impulse. Think of it this way. If Zombie Bruce Lee throat kicks you at full speed, your barbershop quartet days are over. If he does the same move, but 100 times slower, it won’t be any big deal. Even though the “force” is the same, it’s happening so slowly that you won’t feel much of anything.
This is exactly one of the big driving principles behind the Blackhawk! Specops Gen III Shotgun Stock. There are two engineering features that both reduce the force you feel during recoil and spread that reduced force out over a longer period of time. The net result is massively reduced “felt” recoil. Energy doesn’t disappear, so it’s still there. It just gets redirected in lots of fancy ways.
Here’s how it works.
After removing the stock from your standard 870, you attach a small component called the top slide directly to the 870’s receiver. This top slide mounts into the actual buttstock on slide rails. Between the top slide and the stock itself, you’ll find a dual spring system. It’s somewhat like dual recoil springs on compact pistols. The large outer and smaller inner spring give you a recoil dampening effect as the top slide moves into the stock against spring pressure during recoil.