Recoil operated.

Gas guns kick less.

Gas Operated Vs. Recoil Operated Autoloaders, Part 1

By Randy Wakeman


When attempting to compare autoloading shotgun actions, it is easy to break them down into two broad categories: Recoil (short and long) and Gas operated. Further, there are compensating actions and non-compensating actions.

Whether an auto shotgun is called a gas, recoil, inertia, or whatever, it really isn’t the loading part of the shotgun to which we are referring. All self-loading shotguns “self-load” by means of a spring or springs that are compressed during the firing sequence. Many pump-action shotguns will eject shell cases on their own if fed heavy loads and the shooter keeps his hand off the forend. Add the proper recoil buffer and spring to close the action of a slide-action repeater and bingo; you now have a semi-auto shotgun.

It is not quite that easy, of course. After John Browning designed the first truly successful modern repeating shotgun, the Winchester 1897, it took him a while to design the first autoloading shotgun, the Automatic-Five. The Model 97 Winchester, innovative for its day, was quite complicated and retained an exposed hammer. Not only did the A-5 displace the pump action, it also created Browning Arms Company, quite a story in itself.

John Browning’s efforts were prolific; his Model 1896/1899/1900 auto-loading pistols were later improved into the Model 1910 (the gun that was used to start WW I) and continued in production until the 1980’s, along with its variant, the Model 1922. The Model 1910’s recoil spring is wrapped around the barrel, the general design often referred to a “blowback.” However, the Browning design was not the first. The C96 invented by Fidel, Friedrich and Josef Feederle of Mauser was developed in 1895 or so and is now the familiar Mauser 1896 Broomhandle. The inertia spring as found in the Mauser Broomhandle does scant little to absorb recoil, but serves to return its breechbolt back into battery.

With the recoil-operated self-loading pistol so well established by the end of the 1800’s and the delayed-inertia (aka delayed blowback) idea used by Andreas Wilhelm Schwarzlose in Germany in 1902 for the successful Schwarzlose Machine Gun, you might rightly wonder why shotgun semi-autos have proven so problematic (by comparison) over the years. The answer lies in the wide diversity of shotshell loads. While recoil and gas actions were developed for the same cartridge without great difficulty, trouble-free operation with a wide variety of payloads and velocities is an issue that has plagued semi-auto shotguns.

Shotshell propellants, hulls and wad materials were in their early stages when John Browning designed and manufactured his long recoil operated A-5. ("Long recoil" means that the barrel and bolt remain locked together for the full distance of their rearward travel. "Short recoil," the way the Browning/Colt 1911 and almost all high-powered autoloading pistols operate, requires that the barrel only move a short distance rearward before unlocking and allowing the bolt to travel the rest of the way alone on its momentum.)

By proper setting of the bronze friction piece and rings, the A-5 became the first successful autoloading shotgun. It stayed that way with the Remington Model 11, Franchi AL-48 and similar Savage Arms models using the Browning patents by license. Though not a self-compensating design, the Browning system of shock absorber array allowed user adjustment from the standard 2-3/4 inch 1-1/8 oz. loads up to the 1-1/2 oz. baby magnum shells in standard configuration. Its 97-year production history is remarkable, with at least one of its offshoots (Franchi) still being offered in 2009.

The year of 1963 was the watershed year for the gas-operated shotgun; it marks the inaugural year for the largest-selling automatic shotgun in history, the Remington 1100. The Remington 1100 became one of the most influential shotguns of all time, joining the Browning A-5 and eventually surpassing it in sales.

Since 1963, other useable gas autoloaders have appeared. Winchester’s Super-X1 and other short-lived guns like the Browning B2000 and A500G. The Beretta 300 series changed things, along with the similar and Beretta-produced Browning B-80. While the 1100 has endured, two common complaints have surfaced. These are its inability to handle a broad range of shells and its relatively heavy weight. None of these guns compensated for the different gas flow through the barrel ports that operate them.

The A500G, Beretta A303, and Browning B-80 all came with three-inch chambers that could handle 2-3/4 inch to 3-inch payloads, more or less. The “more or less part” reflects right back at the gas action that was not sophisticated enough to compensate. The more gas that goes through the ports, the faster the bolt is propelled backward and the more beating the shotgun (and the shooter) takes. None of this would be an issue if we could standardize what we shoot, but today’s shotgunner apparently wants it all in terms of shells.

Two successful self-compensation designs have emerged, the Beretta 390/3901 and the Browning Gold/Silver/Maxus, also offered as the Winchester SX-2 and SX-3. The difference is the ability of the action to compensate without user intervention.

The Beretta approach was to add a spring controlling a secondary gas bleed beneath the forearm nut, an evolution of the 303 action. Browning designed-in a gas piston with an integral spring that varies the gas bleed in concert with the flow of the shell, now billed as the “Active Valve.” Both systems have been shown to work well, both are the most successful of their kind with Beretta introducing their “391” that offers similar utility to the 390 in a far more complicated, over-engineered manner. That is essentially where we are today in terms of popular and proven gas-operated shotgun designs.

On the recoil-operation front, Browning introduced Val Browning’s short recoil operated Double Auto, a poor seller, and the A500 (renamed the A500R) that became infamous as Browning’s worst semi-auto effort in history. Bruno Civolani offered his 1960’s action design to Benelli, an offspring of the Benelli motorcycle company founded in 1967; that design has developed into what is now marketed as the Benelli “Inertia Driven” action. The inertia idea is a combination of the ideas from the late 1800’s and early 1900’s (Schwarzlose) with the addition of a rotating bolt. Rotating bolts have been used in many sporting arms, notably including the Winchester Model 1400 gas shotgun, Winchester Model 100 rifle and the present day Browning BAR rifle.

As to what is better, we have the usual conglomeration of ad campaigns constantly misrepresenting products. All of the major autoloading shotgun manufacturers these days claim to have the most reliable shotgun. At the same time, they brag of being the softest shooting and the easiest to clean. As usual, they aren’t all being 100% candid. In fact, none of them are.

Benelli/Franchi/Stoeger (all three brands are owned by Beretta) “inertial” branded recoil actions kick more than gas actions, period. Like the Mauser Broomhandle of 1896, the bolt head is blown back where it instantly bottoms out the inertial spring. The more payload your shell has, the more quickly and harshly it bottoms that spring and punishes the shooter. When the spring is compressed, the bolt body unlocks and the “inertia spring” shoots the bolt body backwards, recocking the gun and compressing the recoil spring. The recoil spring pushes the bolt back into battery, feeding a new shell as it does so. It is harsh recoil, harsher than a properly set-up A-5.

However, since the rearward thrust upon ignition moves everything back except for the bolt body and only the inertia spring pops the bolt body backward, there can be no excessive bolt speed, as there can be with both the A-5 and gas-guns, which may result in receiver peening, broken links and so forth. There is less to break and since no gas blows onto the action, there is no gas residue to clean. Recoil operated (including inertia) guns do not tolerate light payloads well. They do handle hot loads well, albeit with a notable increase in recoil to the shooter.

As for modern gas-operated systems, they are not exactly as represented, either. A system that cannot compensate (A303, B-80, 1100) will kick you more as payload goes up, with extra vibration and shock produced in concert with the increased bolt speed. The Beretta 390 compensates. Typically, a harsher shooter than the Browning Gold as supplied, the user can switch in lighter secondary gas springs (Rich Cole) to tune the bolt to a specific load. The newer Beretta 391 can apparently go longer between cleanings than the 390 or 3901, or tolerate more negligent gun care, as the case may be. It is more of a royal pain to clean, however, with a strange barrel nut full of parts that can seize and is very difficult to clean. So difficult, in fact, that Beretta does not even tell you how to do it, or that you should do it.

As to the question, “what is the most reliable?” The answer has more to do with the user than with the best of today’s modern repeaters. It is not possible to say that one gun is more reliable than the others. Used properly, they are all about equally reliable. Bragging about how long you can shoot a gas auto is just about as smart as bragging how long you can run an automobile engine without ever changing the oil. There really isn’t much future in it. If my gun starts jamming four boxes of shells after my friend's gun, not much has been proven, except that neither of us knows how to properly maintain our guns.

As far as current production guns go, the Remington 1100 is still a soft shooter and does a good job if you clean it every 200 rounds or so. It is a good value today and offers a machined steel receiver, albeit at some increase in weight. Not altogether a bad thing, as the extra weight significantly reduces recoil. The Competition grade 1100's come with very nice walnut, engraving and a highly polished blue finish; Premier models have nickel plated receivers and gold inlays. Model 1100's are among the best turned-out repeating shotguns on the market.

The Benelli shotguns are the hardest kicking of the lot. They ask a lot of cash for their plastic stocks, dull metal finish and non-compensating action that prefers you not feed it light loads. No gas action to clean, of course. In terms of fit, finish and value, they are inferior to the Remington and Browning models. The Benelli SBEII/Vinci is still a high recoil option, although the Vinci is billed as being able to handle 12 gauge, 3-dram 1-ounce loads. The new Vinci sacrifices the 3-1/2 shell capability of the standard SBEII for this lighter load handling capability. The basic action remains unchanged from an operational standpoint. All Benelli autoloaders retain the Bruno Civolani platform from the 1960's and have grown a bit dated in terms of features. The primary appeal of the Benelli remains its ability to function despite the lack of regular cleaning.

The Beretta 390/3901 action is Beretta’s best effort to date. It is a pity the up-priced 391 is, in many ways, an advance to the rear. The 391 apparently tolerates neglect longer than the 390, running longer between cleanings, but when you do clean it, it is either obnoxious or nearly impossible. The Beretta 3901 is another good value, but typically is supplied with very low-grade wood and inferior metal finish. The more attractive upscale models, unfortunately, are available only in the complex 391 rendition.

Browning's Silver/Gold are the easiest to clean and the pick of the litter for most hunting applications. Their recent lightweight models have lost ground with trap, skeet and sporting clays shooters; the dedicated clays models have shrunk in the line. The Maxus looks to be a significant advance in trigger, slimmer forearm, ease of cleaning and even less cleaning required; it is well worth investigating.

At the end of the shotgunning day, we have recoil-operated guns that claim to be soft-shooting and gas-operated guns that are promoted as easy to clean or self-cleaning. Far closer to the truth is that gas guns will always be softer shooting than recoil guns. Recoil guns will always need less routine cleaning than gas guns.

Go to Part 2

Gas Operated Vs. Recoil Operated Autoloaders, Part 2

By Randy Wakeman


This discussion quotes excepts from a public document, courtesy of the U.S. Patent Office. It is patent US 7,707,923 B2 of May 4, 2010. Several types of semi-automatic shotguns are known, the operation of which are based on different principles.

GAS OPERATED ACTION

The first type of semi-automatic shotgun we will examine is called “gas operated.” In such shotgun, the energy of the gases developed by the powder explosion is exploited. A small part of such gases is drawn from the barrel through one or more holes, in order to generate an expansion inside a cylinder closed by a sliding piston. The piston thrust generates, in turn, an impulse that recocks the mobile masses, ejects the shell and loads the new ammunition.

The piston thrust is extremely variable as a function of the force of the primary impulse generated in the chamber by the powder explosion. Such primary impulse depends on the gram weight of the cartridge which is fired, where “gram weight” means the mass of the charge of fired pellets, therefore the power of the same cartridge. The mass of the powder charge and the mass of the pellets charge are typically proportional.
The gas-operated device, in order to be able to ensure the required reliability, must necessarily be dimensioned for the operation with those cartridges having the lowest gram weight that can be chambered in the shotgun. Once the device has been properly dimensioned, the variability of the cartridges gram weight and the consequent primary impulse translate in a variability of the recocking speed. The minimum speed is the one which is necessary in order to achieve a safe operation of the weapon when a cartridge having a low gram weight is fired. The maximum speed corresponds to the firing of a cartridge having the maximum gram weight that can be chambered in the shotgun.
However, the high recocking speeds translate to high stresses and, consequently, to a decrease of the working life of the shotgun components. In the more modern gas-operated shotguns, it has been successfully attempted to obviate the problem of the high recocking speeds by adopting shutter or self-compensating valves, which are able to exhaust the excess gas associated with the firing of cartridges having a higher gram weight.
However, such valves, or venting systems, involve an increase of the mechanics and the cost for the shotgun. Furthermore, gas-operated systems require maintenance, since the gas which is vented tends to foul unburnt solids, which have to be removed after firing a large number of shots.
INERTIAL / RECOIL ACTION


Another type of semi-automatic shotgun is the one called the “inertial” type. In this type of shotgun, the compression and the subsequent relief of a spring that is arranged between the mobile masses and the shotgun frame are exploited. The spring compression is caused by the shotgun recoil and it is exploited in order to confer to the same masses the required recocking speed.
The shotgun with inertial operation is appreciated because it allows limiting the maximum recocking speeds and results in a reduction of the stresses on the mechanical parts. Furthermore, the inertial shotgun is characterized by constructive simplicity and reduced maintenance. In fact, not requiring any gas drawing, the inertial device itself does not undergo any fouling. Of course, the standard cleaning is still necessary for the chamber and the barrel, which are contacted by the firing gas.
In contrast, the low recocking speed, which is intrinsic of the inertial shotgun, may be a problem, especially when the shotgun frame has a high mass, and the fired cartridge has a low gram weight. The low recocking speed translates in a low shell ejection promptness and a high risk of jamming. In addition, the operation of recoil operated shotguns is highly affected by the user's behavior, particularly by the type of reaction that the user opposes with his/her shoulder to the shotgun stock. This patent was apparently used to cover the now discontinued Beretta UGB 25 and is by Ugo Beretta. it covers self-loading shotguns in a far more frank and less flattering manner than most advertising copy.
PROS AND CONS

Excessive bolt speed and associated wear is a potential issue. When seeking the “shoots everything” gas autoloader, the 12 gauge that we might brag handles our wimpy 7/8 ounce reloads is a poor choice for a steady diet of higher intensity, 1-1/2 ounce loads, with resultant high stress and comparatively short parts life.
While this discussion is not particularly flattering to gas autoloaders, it also frankly describes the problems of inertial guns, whether due to a heavy gun, light loads, a combination of both and function is affected by how the individual holds the gun. In a solid fixture where rearward movement of the gun is eliminated, the inertial action will not function, but a gas operated action will.
While Beretta describes the maintenance of the gas gun as constant, that isn't strictly true. Regular cleaning is required, but the intervals vary from model to model. The most important potential benefit of gas operation, softer and more comfortable shooting due to a lower amplitude, longer recoil pulse is ignored.
The inertial action, along with its predecessors, the long recoil action (Browning Automatic Five) and various short recoil actions (Double Auto, A500) does shoot cleaner and requires less maintenance. The inertial action is cheap to make. Whether they are marketed cheaply is another matter, but there are comparatively few parts to machine and assemble. The inertial action can generally be a lighter action, due to the complete lack of gas pistons, seals, piston shrouds, action rails, valving, etc.
While Beretta sure doesn't seem enthused about either gas or inertial actions, things are not as dire as their comments suggest. The most influential gas gun, the seminal Remington Model 1100 of 1963, showed off the soft-shooting potential of gas shotguns by virtue of its 7.5 pound weight and its gas system. It improved on its predecessor (the Dial-A-Matic gas regulating cap Model 58) by eliminating load adjustment by the user. It still needs 300 shot or so cleaning, but it popularized the gas shotgun like no other. Note that the Dial-A-Matic, sometimes called "dial a duck," compensated only for 2-3/4 inch shell variations, like the standard Browning A-5 and Remington Model 11 long recoil operated shotguns.
The system used by the Beretta 302 / 303, Browning B-80 and Browning B2000 of changing the barrel as needed from 2-3/4" to 3" chambering took care of the excessive ejection distances and bolt speed. It was and is a very good system, but changing barrels has lost its appeal. The 1993 Browning Gold (Activ Valve) platform was simplified and improved in 1999 with the Winchester SX-2 that now is the Browning Silver (in 12 gauge). This platform is also the FN SLP; two Active valve pistons are supplied with the SLP and some SX2 Models.

Most folks know whether they are going target shooting or turkey hunting, so getting your bolt speed down to a 4 – 6 foot ejection distance is a good idea to reduce stress, vibration and get the most out of your gas gun. You have that option with a Beretta 390 or 391 with a secondary gas bleed spring set from Cole Gunsmithing, or piston switching with the Gold / Silver / SX2 / SX3 / SLP platforms. The Weatherby SA-08 gives you a pair of pistons with each shotgun for just that purpose. That, and a new mainspring every 6000 rounds or so, will help you get the most out of your gas gun, even if it not absolutely needed.

Gas Operated Vs. Recoil Operated Autoloaders, Part 3

By Randy Wakeman


As published in an Ugo Beretta patent, gas-operated autoloading shotguns can have their problems:

“The high recocking speeds translate in high stresses and, consequently, in a decrease of the working life of the shotgun components. In the whole, this results in a short duration of the same shotgun. In the more modern gas-operated shotguns, it has been successfully attempted to obviate the problem of the high recocking speeds by adopting shutter or self-compensating valves, which are able to exhaust the excess gas associated to the firing of the cartridges having a higher gram weight. However, such valves, or venting systems, involve an increase of the mechanics and the costs for the shotgun. Furthermore, the gas-operated systems require a constant maintenance, since the gas which is vented tends to foul unburnt solids, which have to be removed after firing a number of shots.”

However, inertial actioned shotguns have their issues, also mentioned in the same patent:

“The low recocking speed, which is intrinsic of the inertial shotgun, may be a problem, especially when the shotgun frame has a high mass, and the fired cartridge has a low or very low gram weight. The low recocking speed translates in a low shell ejection promptness and a high risk of jamming. Furthermore, the operation of such type of shotgun is highly affected by the user's behavior, particularly by the type of reaction which the user opposes with his/her shoulder to the shotgun stock.”

From the less than enthusiastic description in the Ugo Beretta patent, it sounds likes Mr. Beretta doesn't much care for autoloading shotguns at all. We might be under the impression that shotguns are designed to be strong and to last a long time, but they certainly aren't. (High quality double guns are! -Editor.) They are designed to have fun with, for the most part, and that means light enough in weight to be carried between the hands and swung easily. Shotguns do not need to be strong, in the sense of resisting high pressure, for a shotshell is a low pressure cartridge compared to even a .22 rimfire short.

The cost of shooting isn't just in the shotgun, for a case of cheap Estate target loads runs about $55 in 2013, or twenty-two cents a shot. 50,000 rounds, even if only target loads, is $11,000 and there are clay targets, range fees and so forth on top of that. Prices vary, but a round of skeet may cost you $5, or $10,000 for those 50,000 shots. Now we are at $21,000, more in some areas, more for sporting clays, much more for hunting ammo and so it goes. Of course, we do squander some pesos on food, water and transportation.

Those looking for a snappy answer as to which type of autoloading action is the mythical best won't find much comfort. Some of the most heavily used shotguns on the planet are Argentina outfitters' rental guns, which are 20 gauge more often than not. Those searching for the most reliable autoloading shotgun won't be happy with the answer based on this experience: The inertial Montefeltro and the gas-operated A390 are the two winners, according to Hayes & Hayes.

The Original: The Long Recoil Operated Browning Automatic-Five

The grand achievement of the A-5 was not that it was the best of any breed; it was a new breed, a long recoil operated autoloading shotgun. The most remarkable thing about it is that it worked at all. The shotshells of the day were variable, so it wasn't about firing different loads interchangeably, as much as it was being able to use different brands of shells at all, for shells varied significantly by brand. That it had no competition for fifty years makes it all the more remarkable.

The A-5 cycles faster than either the Remington 1100 or Benelli (Bruno Civolani), actions that came along over sixty years later. It lacks the low recocking speed of the inertia action and gas fouling is not an issue. However, cost of manufacture was an issue and using three inch shells required a whole new receiver, which, in part, helped to end the reign of the A-5 as a production gun. (A barrel that recoiled inches back into the receiver and prevented the use of a full length ventilated rib, the hump back receiver that most found ugly, overly generous drop at comb and the double-shuffle recoil were other factors that helped end the A-5's long reign, once viable alternatives became available. -Editor)

The Current Inertial (Short Recoil) Actions

While the basic action function hasn't changed much from the Bruno Civolani design acquired by the (then) Benelli Motorcycle Company, variations continue to appear, such as in the Benelli Raffaello that adds another recoil-attenuating system to this 2950 gram (about 6-1/2 pounds) autoloader. This one is called the "Progressive Comfort." The inertial action remains simple, is cheap to manufacture and low relatively maintenance. The action itself kicks like a fixed breech gun and there is no way around that. (Comfortech and now the Progressive Comfort stock are add-ons that try to soften the recoil jolt.) It cannot handle the wide load intensity spread of the better gas operating systems. Inertial actions can make good hunting guns, but they cannot compete with the better gas guns for high volume shooting, such as trap and skeet shooting.

It is guns like this and the 6-1/2 pound (12 gauge) Browning A5 "Kinematic" inertial offering that have further cemented the demise of the 16 gauge. If you use these 12 gauge guns with classic, one ounce, 16 gauge type shot loads, you'll probably be delighted. If you like a steady diet of heavy payloads, you just might find yourself wishing for a heavier gas gun.

The Current Gas Actions

While at one time an autoloader that actually worked was quite an accomplishment, we sometimes decisionally-challenged shooters continue to confound manufacturers. We always want what physics does not allow: light guns with no recoil. Some clays shooters claim "3/4 ounce of shot is all you need," while some hunters lament that 3-1/2" shells don't hold enough steel and that four inch magnums would be more effective. It has created quite a mess, for a 12 gauge gas auto that functions with 7/8 ounce loads, at least for the most part, has excessive bolt speed, vibration and wear with 1-7/8 ounce or 2 ounce loads. It normally isn't comfortable, either. Thus, we have the pogo stick, recoiling buttstock things that started with the patented Hydro-Coil (featured in Sports Illustrated Sept. 9, 1963), claimed to reduce recoil by as much as 85%. For a while, Hydro-Coil stocks were an option available from Olin-Winchester.

A) Non-compensating Gas Actions

While the Remington Model 58 required user adjustment for "low brass" or "high brass" loads with the Dial-A-Matic cap, shooters sometimes left it at the low setting and promptly blew off the cap via 1-1/2 ounce, 2-3/4" Magnums, or similar, loads. The most popular non-compensating action was the Remington 1100, introduced in 1963. Back in the day when only two 12 gauge loads were common, 1-1/8 ounce load for targets / light birds and 1-1/4 ounce for pheasants / ducks, it did just fine. The later Beretta A302 / A303 / Browning B-80 actions did better, going three or four times as long without cleaning. While also non-compensating, bolt speed is regulated by a barrel change: use a 2-3/4" chambered barrel for target loads through 1-1/4 ounce hunting loads, use a three inch chambered barrel for 1-1/4 ounce, 1330 fps and heavier loads.

The Beretta M4 and Remington Versa-Max, using twin gas pistons, are claimed to be self-regulating, but are not. They claim to be self-cleaning, like most gas shotguns. However, like all gas shotguns, you do have to clean them; some more often than others, that's all.

B) Compensating Gas Actions

Many gas guns required a manual adjustment or a barrel change to operate with different ends of the load spectrum. The Beretta A390 added a secondary gas bleed to the 302 / 303 system, so the three inch chambered guns could handle 1 ounce target loads on up with no adjustments. Apparently aware shooters would be quick to gripe about jamming with pipsqueak loads, the secondary gas bleed springs factory supplied were overly stiff. Cole Gunsmithing fixed that for the 390 (and the later 391) by offering spring kits so you could tune your bolt speed and resultant ejection distance to your loads.

In 1993, the Browning Gold was released with its "Active Valve." With springs integral to the piston itself, it has proved to be a softer shooting action than the Beretta releases. Still, to get the most out of it, F.N. has released different pistons for the heaviest loads.

In 2003, FABARM released its Pulse Piston system, using the gas to expand the elastomeric seal of the piston against the magazine tube to control piston speed. That does away with secondary gas bleeds and associated springs. The result is a gas action with friction compensation hybrid.

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Huge read I know but when your done you know everything about gas and recoil operated shotguns.