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Cooking with Gas

By John Haviland

Cooking with Gas
Self-shuckers like the Remington 11-87 (left) and the Beretta Extrema2 produce the same amount of recoil as fixed-breech guns. However, that kick is spread out over a longer period of time, and with less of an energy spike, it feels like less recoil.

Only a few hits upside the head from hard-kicking shotshell loads were required for me to realize I can hit more ducks and clay targets when my gun kicks a little less. A gas-operated autoloader is a big help in softening the recoil of those hammering loads, and that can lead to a better day in the field.

“We all flinch when we shoot a shotgun,” says Scott Grange of Browning and Winchester. “It’s just a matter of how much we flinch. When you’re shooting a gas gun, though, the slightly softer recoil is going to make you less likely to yank the trigger and lift your head off the stock comb in anticipation of getting kicked while shooting 200 clays over a day.”

That gentler kick also helps keep your sight picture after firing a shot. That can give you a moment’s more time to align your gun on a second or third target.

When my wife went shopping for a 20-gauge shotgun for pheasant hunting, she shot pumps, side-by-sides, over/unders and recoil- and gas-operated autoloaders. The Browning Gold gas gun softened the sharp kick the other guns created when shooting high velocity 11Ú8-ounce loads. When I threw her a clay pigeon and then another one right after it, she got on the last target the quickest with the Gold autoloader.

That easier recoil definitely helps when shooting some of today’s waterfowl loads. Last December, I shot Federal’s High Density 12-gauge 3-inch 13Ú8-ounce shells at eiders, scooters and other sea ducks along the Maine coast. The Beretta Xtrema2 gas gun handled those loads with ease and the recoil felt like a sock from a pillow.

I shot quite a few boxes of those magnum loads at the sea ducks in the morning and in the afternoon at puddle ducks farther inland. There’s no doubt I would have been rummy after shooting that much with a pump. In fact, shooters on our boat ran low on shells, so I reluctantly volunteered to shoot 31Ú2-inch steel shells that looked like little sticks of dynamite. The recoil was certainly there. But the Beretta did a good job of dampening the sharp stab from those shells, and I was able to swing on through the ducks and see my hits.

Cooking with Gas
These waterfowlers are shooting at ducks with Beretta Xtrema2 gas guns.

In theory, a gas-operated shotgun develops the same amount of recoil as a fixed-breech gun such as a pump. But that kick is spread over a longer period, so there’s less “felt recoil.” Brad Howard of Beretta says you really can’t get around physics, so a gas-operated gun and a fixed-breech gun do produce the same amount of recoil. “However, if you looked at a graph of the amount of recoil for the fixed-breech gun, you would see a sharp spike in the recoil in a short amount of time,” he says. “But the same type of graph of recoil for a gas gun shows that amplitude has been reduced and spread over a longer time. Or in other words, that snap of the kick has been rounded off.”

That little less whack every time you pull the trigger definitely helps over the long run. “Shooting fatigue is certainly cumulative,” Howard says. “So if you can reduce that peak spike of recoil 40 percent for every shot you take, that’s going to turn into a huge advantage during a day’s shooting.”

Dwight Potter, an engineer for Browning and Winchester, says there is a slight reduction in recoil. “There really is less energy coming back into your shoulder,” he notes. When a gas gun first fires, the expanding powder gases push the shot column forward down the barrel and the shotgun backward into your shoulder. As the rear of the shotcup passes the gas port about halfway down the barrel, some of that gas is bled off into the gas piston. “Now, it takes time for that gas to reach the piston,” Potter continues. “And in that time, the shot column is farther down the barrel nearly to the muzzle.”

That bled-off gas isn’t contributing to the rearward motion of the gun. In fact, the gas that has gone through the gas port and is pushing on the gas system actually pulls the gun forward somewhat. Those two factors reduce recoil. The right timing of the gas piston moving rearward and the spring compressing can also reduce the sharp stab of recoil.

“That’s how it works physically,” Potter says. “But in reality, can you feel the difference? If you shoot five shots, you probably won’t notice it much. But if you shoot several hundred rounds, I think you will.”

A Dirty Job

Those same gases that help treat your shoulder kindly are also responsible for the gas gun’s finicky reputation when it comes to cycling different loads and to keep on shooting without cleaning.

“It would be great if everyone shot the same load,” Potter explains. “Then we could make a certain size gas port and a solid gas piston to work with that one load.”

But that’s far from the case. Shooters expect their shotguns to cycle loads with light amounts of powder and shot for clay targets. The next time out, though, they want the same shotgun to handle magnum turkey busters or steel-shot loads that will drop geese from the clouds. Those heavy loads provide plenty of gas to cycle the system, and no springs are really needed to slam the action closed. “With heavy loads, you really need a gas system that negates the effects of the gas,” Potter says. “Everyone says they make a ‘self-regulating gas system,’ but in truth, these heavy loads hit so hard that gas is actually vented back into the barrel after the shot column has left the barrel.”

For light loads to cycle a gun’s action, though, a system is needed that amplifies the effect of the gas coming in through the port. In many systems, this is done with a spring that compresses as the system travels to the rear, then springs back to help close the action.

“That’s the challenge,” Potter continues, “to use all the gas you can to cycle light loads and dissipate it with the heavy loads.” Potter says an ideal way to do that would be a switch to vary the size of the gas port. “But then, of course, someone would forget to turn back to the small port when he started shooting heavy loads. Then he would probably end up with a wrecked gun.”

Some well-intentioned basement gunsmiths have bored out the gas port on guns thinking it will make the guns cycle reliably with lightly loaded shotshells. This is usually done in the belief guns with lengthened forcing cones and overbored barrels don’t develop as much pressure, and therefore need a boost to keep the gun working. “Backboring and all the other things have already been figured in when a gas system is designed,” says Scott Grange. “All that will happen is a person will switch to shooting heavy loads, and after a while, all that extra gas will bust up his gun.”

Browning and Winchester guarantee their 12-gauge 3 1/2-inch gas guns will cycle loads all the way down to 1 1/8-ounce target loads. “There’s a fine line of how light of a shell they will reliably cycle,” Grange says. “A lot of the time, they will even work with the 7/8-ounce loads.”

Last year, I shot a Winchester Super X2 3-inch 12 gauge with nearly every shotshell I got my hands on. The gun threw the empty cases from 3-inch steel and turkey shells five long paces out of the gun. The gun fired box after box of reloads with 1 ounce of shot at 1,200 feet per second.

The secret that kept that gun shooting was I kept it clean, because gas-operated shotguns do tend to gum up and jam. “Face it,” Grange says, “if you don’t like to keep your shotgun clean, then you’ll be better off shooting a pump.”

Contrary to popular belief, gas ports do not plug up. “There’s enough high-pressure gas shooting through there to keep it open,” Grange says. What usually happens is grime builds up over time and slows the working parts enough that the action becomes somewhat out of time or completely seizes up.

“Say you’re out duck hunting in the rain all day,” Grange says. “The water trickling down through the action of your gun is going to settle in the main-spring tube at the back of the action.” If left unattended, the spring and tube are going to corrode and seriously affect the performance of your gun.

“We make our gas guns as simple as possible because we know you will have to take them apart to clean them fairly often,” he continues. To properly clean a gas-operated autoloader, Grange suggests pulling out the trigger assembly and removing the bolt, gas piston and mainspring and give the gun and every part a thorough scrubbing.

Some shotgunners like to leave the clean parts dry because they think oil attracts dirt. Grange prefers to wipe a fine film of oil on the parts. He gives the magazine tube a wipe of 30-weight engine oil. “That tube gets hot from a lot of shooting, and a thinner oil will burn right off,” he says. Brad Howard says the gas system on Beretta shotguns is unlike other systems because it does not have O-rings to seal the gas system. On the Beretta 391 models, a cylinder is attached to the bottom of the barrel and encloses the gas ports. A piston rides inside the cylinder, and a series of grooves inside the piston act like little scrubbers to keep carbon from building up and also serve as a gas seal. Gas entering the gun flows into the first groove and circles around and fills the next groove and the next. “The more grooves that fill with gas, the less gas is able to leak past, and that’s how we get the gas seal,” he says.

Subscribe Today!Beretta specifies that its AL391 Urika 12 gauge will reliably cycle loads from light-recoiling 2 3/4-inch shells with 7/8 ounce of shot up to heavy-kicking 3-inch shells with 2 ounces of shot. Its Xtrema2 will function with 3 1/2-inch shells down to 2 3/4-inch loads with 1 ounce of shot and a 3 1/4-dram equivalent. “Guys tell me they commonly shoot 1,500 rounds with no problems with jamming,” Howard says.

Rick Noel, my trap-shooting partner, fires his AL391 Urika 12 gauge at least 700 times during trap league. “Over all those weeks of shooting, I never cleaned the gun, nor did I have any jams,” Noel recalls.

Howard says gas guns have gotten a bad reputation from older designs that failed to work well. “Today’s guns are designed a lot better, and cleaning is really not an issue,” he says. Combine that with the softening of hammering waterfowl loads and easing the collective effect of shooting many target loads over a day, and the gas gun provides a definite advantage over other shotgun designs.

Reprinted from the December 2006 issue of Buckmasters GunHunter Magazine

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