6 Steps To Slug Gun Accuracy
October 12, 2011
TIP NO. 1
Spin It With Barrel, Choke Tubes
Your first consideration with any slug gun accuracy is the barrel. After all, that's where the launch is initiated and where everything that forms the direction of flight takes place.
If you use your smoothbore barrel for other hunting and shooting, try different choke tubes to see which handles your slugs best. You may find that improved cylinder handles certain slugs better than modified, or vice versa. I've seen a few skeet and even full-choked guns that threw rifled slugs very well. You simply must experiment.
Virtually every shotgun manufacturer now offers a rifled choke tube for its guns, and there are plenty others on the aftermarket. You should know that you're wasting time and money shooting sabot slugs through a smoothbore. Sabots are designed to be spun by rifling to achieve stability in flight.
You'll probably find better slug gun accuracy out of a rifled choke tube if you're using lower-velocity sabot slugs such as Lightfield Lites, Winchester WinnLites, Federal's Reduced Recoil or Remington's Managed Recoil slug loads.
While a choke tube will have an effect on how well your gun shoots slugs -- and a rifled choke tube will allow you to take advantage of the superior performance of sabot slugs -- the best step toward dedicating your shotgun to slug shooting is a fully rifled barrel.
Although a good rifled choke tube may provide accuracy close to that of a rifled barrel at 50-75 yards, it simply can't be expected to spin the slug sufficiently to stabilize it as far as a rifled barrel does. You don't have to be a mechanical engineer to see that it's asking a lot of 2-5 inches of rifling to impart 40,000 rpm spin on a projectile that's already traveling at peak velocity when it hits the grooves. Obviously it's simply more efficient to spin it from the chamber to the muzzle.
Every major shotgun manufacturer today makes at least one model with a rifled barrel, and most also sell the rifled barrels separately. Rifled barrels are typically made of rifle-ordnance steel, which is much denser and reduces harmonics.
Hastings Barrels and Badger Barrels are currently the only aftermarket locations for rifled shotgun barrels other than custom shops, and the offerings are very limited.
Another fix is the Sims Sharpshooter X-ring dampener that can be fitted to the barrel to adjust harmonics.
TIP NO. 2
One cure for taming harmonics in a slug gun is to affix the barrel to the receiver. Pinning the barrel to the receiver (have a gunsmith put a cap screw through the receiver wall and barrel shank to essentially make them one piece) will take a great deal of the accuracy-destroying vibration out of the system.
Pinning -- or using epoxy or shims on models with shorter barrel shanks -- is one move that will make any barrel, smoothbore or rifled, shoot more accurately because it eliminates sloppy barrel-to-receiver fit. Ithaca's Deerslayer II models are the only pumps with free-floating barrels (no magazine lug) affixed (epoxied) permanently to the receiver.
If you are having problems with a rifled barrel, they can usually be corrected by smoothing or polishing the crown or the forcing cone.
TIP NO. 3
Port The Barrel
Barrel jump increases felt recoil. Porting reduces jump, disturbs muzzle gases and allows sabots to break away freely.
Mossberg has been porting most of its shotgun barrels for years, and Hastings also offers ported barrels. Virtually any barrel can be ported, if you find the right shop. The best I've seen is a ported compensator that is designed and installed by Da-Mar Gunsmithing in upstate New York. It makes a remarkable difference in felt recoil and barrel jump without effecting accuracy at all.
Barrel ports must be kept clean; They tend to shave sabot sleeves and collect debris that can effect flight of subsequent slugs.
TIP NO. 4
It's a major factor in consistent shooting. A typical shotgun trigger is designed to be slapped, not squeezed like a rifle trigger. And gun companies' liability lawyers like to see substantial creep in triggers that are also set for a hearty slap. The fear is slam-fire on recoil. Manufacturers err on the side of caution here.
One of the exceptions is Savage's Accu-Triggers, which they started putting on their 220F and 212 bolt-action rifled barrel slug guns in 2010. Mossberg has a similar system they call LPA (Lightning Pump Action), which is also adjustable. Remington used different springs to lighten and stiffen the trigger on its 870 and 11-87 slug-shooting models.
But for any other slug gun to shoot accurately you must lighten and stiffen the trigger. I don't care if you're the type who can crush cueballs with your fist, nobody can wring full potential out of a firearm with an 8- to 10-pound trigger pull. In a perfect world, we'd have slug guns with crisp 3- to 3 1/2-pound pulls. But in this world, even a 5- or 6-pounder isn't bad, as long as there's no creep.
Many gunsmiths won't work on triggers because of liability or the fact that such an adjustment voids the gun's warranty. But anybody who does work for trapshooters will likely do it for you.
Timney Triggers offers an 870 Trigger Fix kit. It's essentially a modified and adjustable replacement sear and springs that will allow a Remington 870 trigger to be adjustable from 1 1/2 to 4 pounds with no creep. At $89.95 it's a bargain, and if you have any knowledge of triggers at all, you can install it by following illustrated instructions on the Timney Triggers Web site.
Unfortunately, no one offers "trigger fixes" for other models or brands of shotguns. Some guns can be adjusted by anyone with the knowledge and a hone. Remingtons, Ithacas, Berettas and Benellis are fairly adjustable; Mossbergs and Winchesters are not.
For those guns, I've been using the E-Z Pull Trigger system. At $40, it's an eminently affordable alternative to gunsmithing, fits all makes of shotguns and invariably reduces pull by at least 50 percent while eliminating creep.
TIP NO. 5
Adjust Comb Height
The comb must be high enough to allow your eye to look through a scope while maintaining solid contact with your cheek. If you ride higher on the comb, you won't get a consistent look through the glass, and the gun will kick you harder.
Mossberg has long offered a unique adjustable comb system on its Model 500 pump. Remington fits its 870 and 11-87 Special Purpose Deer and Turkey models with an optional rollover comb thumbhole stocks made by Boyds or the ambidextrous ShurShot stocks. Bell & Carlson, and other aftermarket companies, make high-combed or rollover synthetic stocks to fit popular model shotguns.
Actually any normal shotgun stock can be brought to the correct cheek position with a strap-on Monte Carlo trap pad from Cabela's, a foam version from Beartooth or a stick-on adjustment from Cheek-Eze.
TIP NO. 6
Add Recoil Reducer
There are few firearms that kick harder than a shotgun loaded with slugs. The typical 7 1/2-pound, 12-gauge recoil is roughly equivalent to a .375 magnum rifle or heavier. Anything that makes a slug gun less punishing to shoot will definitely make it easier to shoot accurately.
The laws of physics make recoil an elemental fact -- a particular load will exert a specific amount of reaction. It's the same poundage, regardless of gun -- but it can be made to feel different. Thus, we are dealing with "felt recoil", and thankfully, there are ways to mitigate that.
As a rule of thumb, heavier guns feel like they kick less than lighter ones. Autoloaders are designed to suppress felt recoil more than pumps, single-shots or bolt-actions.
Some Benelli pumps and autoloaders have recoil-suppression devices in the stocks, but they are an exception.
There are a variety of recoil-reduction devices for those shotguns that don't have them built-in. Mercury-filled tubes that can be inserted in the stock or magazine tube of your shotgun are very effective at suppressing recoil. There are also a variety of specialty recoil pads to add to the effectiveness. Sorbothane models like Kick-Eez are very effective, as are collapsible models like Pachymar Decelerators or the Sims Limbsaver (Remington's R3 is virtually identical to Sims) or Hi-Viz pads.
So don't be discouraged about the performance (or lack thereof) of your current slug gun. The bad news is that right out of the box most slug guns won't be tack-drivers. But the good news is that most all of them can be made to shoot better.
--Dave Henderson is the author of several books on shotgunning and hunting. Reach him at HendersonOutdoors.com.