A Glimpse at Shotgun Gas Actions The gas-operated semi-auto shotgun is the most important "revolution" of sorts in the last fifty years of scattergun shooting. Bob Brister described the felt recoil dampening extremely well, in his must-have Shotgunning: Art & Science, using the Remington 1100 as his example. The recoil reduction industry is a huge one, with some rather strained approaches touting tangible benefit. My shoulder tells me that most either don't work, or are grossly over-rated. Confusing the issue with common sense, the first stop is physics. Shotgun weight affects recoil on approximately a "one-to-one" ratio. Add 10% to a specific shotgun's weight, it kicks about 10% less. Lighten our shotgun by about 10%; it kicks about 10% more. That's all there is to it. Muzzle velocity and ejecta (wad, shot, etc.) both affect recoil approximating a "two-to-one" ratio. Bump up the muzzle velocity by 10%, recoil increases by 20%. Increase our payload by 10%, again the free recoil goes up about 20%. That also, is about as simple as it gets. There are all kinds of ballistic programs that will give you a number to go along with it, if you need it, but that's about all there is from a "free recoil" standpoint. The matter of "felt" recoil is subjective, and most anything can be claimed in that department--and has been. A more detailed look is at http://www.chuckhawks.com/shotgun_recoil.htm Nothing kicks harder than a fixed breech gun. Properly set-up recoil actions do attenuate recoil quite a bit, but gas guns are easily the softest shooters. If recoil is significant to you, as it is to anyone that shoots enough to discover the effects are cumulative, a gas-operated shotgun the sole answer to get major reduction. There have been other notable approaches, such as the single shot Browning Recoil-less (it works), but the topic here is repeating shotguns suitable for field or clays work. When it comes to gas-guns, reliability is often questioned. Properly maintained gas guns are every bit as reliable as any other shotgun. I have a steel-received Browning B-80 with over 100,000 rounds through it as personal testimony to that, with no major parts replacement in all those rounds, just periodic recoil spring replacement. Many military weapons are of course gas-operated, putting far more on the line than just the turtle dove that might get away. Complete reliability does not address gun neglect, though, nor does it mean poor ammo. Over the years, gas-operated shotguns have been developed to the point where reliability is not an issue, within reason. Reasonable use does not mean avoiding all maintenance, nor does it mean firing with bore obstructions or clumsily dropping your shotgun into the mud. Modern gas valving can accommodated a wider spectrum of loads than can simple blow-back with a spring (misrepresented as 'inertia' actions) or long recoil actions as embodied by the wondrous Browning Auto-5. It is hard to mention gas autos without speaking of the Remington 1100; certainly the most influential of the breed for many years. From its introduction in 1963 through the mid-eighties, it was a runaway hit. It began getting a little long in the tooth with its inability to handle a wide variety of loads, though, and Remington seemed to be aware of that. Then, Remington introduced the Model 11-87 (in, coincidentally, 1987), but vacillated a bit. They were unable to displace the 1100 as they appeared they were trying to do. An O ring in an uncaptured, exposed condition is a weak link. Static O ring applications are far easier than dynamic applications. Over time, rubber cuts steel. Those familiar with the Chicago Rawhide "Waveseal" will readily understand that. In fact, the Winchester SuperX1 acknowledged the magazine tube scrubbing and wear-it was reversible, so you could get effectively twice the life out of the magazine tube. The most common 1100 failures are still O ring related; apparently Remington is having trouble removing burrs from their gas ports these days. If chunks are quickly missing from your O ring, it is a manufacturing defect, an all too common one. Now, the limitations of the 1100 became a bit more transparent, as a "Barrel Seal Activator" (Remington term) has to be added or removed for reliable operation in 11-87 20 gauge models, as well as the 11-87 Super Magnum models. Both guns have lost ground, failing to gain traction ever since. The Remington QC problems are not helping. The American shooter is a fickle one; even the simple friction piece adjustment on the timeless A-5 has baffled us. Beautiful gas actions have come and gone, as we have failed to embrace the Browning B-2000's elegant internals, the Winchester SuperX1 was an expensive flop, and Browning's A-500G lasted only two years in production. In the case of the A500G it was ergonomics rather than the action that doomed it, along with the less than stellar reputation of the A-500R. There was, and is, better approaches than O rings and other simplistic gasketed designs: the SKB XL900 has faded from view, along with many other models. The Beretta A302 / A303 / Browning B-80 (1981 to 1991) lost the O ring, proving reliable with fast 1 oz loads up to the heaviest 3 inch shells, though both 2-3/4 in. and 3 in chambered barrels were available. Even the rankest novice could clean them and get them together the right way, with losing no parts. Additionally, factory stocks were now user adjustable for drop. The Browning B-80, particularly in its steel-receiver model, proved to be a smooth swinger and a soft shooter. The A300 / B-80 gas system is non-compensating; the more gas you give it the faster the bolt comes back. It is also a fairly dirty action, as the gas coming back has nothing to prevent it from coating the links and bolt. Easy to clean up, though, and as it is immensely durable made it remains one of my favorite gas guns. B-80's take doves and pheasants for me every year, and did famously for me in Argentina as well as high-volume snow goose hunting. The Beretta A390 was an outgrowth of the A303; adding a secondary gas bleed system. Finally, a design that could finally compensate. As supplied from the factory, it rarely did so perfectly, but with Rich Cole springs you could easily tune a specific A390 to a specific load, getting reliable 10 to 12 foot ejection with no receiver peening. Though the 390 and the newer 391 action are billed as "self-cleaning," that notion is a bit of tortured humor. I've spent a lot of time cleaning self-cleaning actions. The grunge in the 390 gas piston (and the corresponding housing attached to the barrel) is easy enough to clean out with a pipe fitter's brush; the same goes for the 303 / B-80. The Beretta 391 action is more of a step backward than an improvement as far as I'm concerned compared to the 390. It succumbs to the over-complication for complication's sake that doomed prior gas guns. Witness the Urika 391 forearm nut (called a fore end "cap" by Beretta) that is comprised of seven parts. It is an over-complicated mess as far as I'm concerned. Nevertheless, the Beretta A390 design is one of shotgunning's best, now available again as the 3901 series. While all this was going on, Browning introduced the "Gold" in 1994. Over the last 12 years, it has developed into clearly the best semi-auto gas system on the market. I'm not privy to the fine points and running production changes of the Gold system, but I can tell that there have been refinements. I've been advised that older gas guns were ported for lead loads, current gas systems for steel, but I have no idea exactly what that means. I do know that SAMMI gives shotshell manufacturers 12,000 PSI or so to work with, and H. P. White data shows that 2500 to 3000 PSI is often what is left near the muzzle. The exact pressure past the ports is something that Browning and others monitor, as difficult a task as that likely is. The beauty of the Gold system is one valve assembly, no loose O rings or concoctions of loose springs. I won't call the Gold self-cleaning, but what residue remains after firing forms right on the magazine tube making it breathtakingly easy to get to and wipe off. Today's gas systems reviewed in a nutshell would be that Remington had it, but lost it, Beretta found it but didn't know what to do with it, but thankfully re-released it, and Browning finally got it, and has it. Part of the issue is that we seem to expect too much out of one system with no adjustments. We think we want the ability to shoot 2 oz. loads, and we think we need to shoot 7/8 oz. loads out of the very same gun all with complete ignorance of what a gas system must necessarily handle. We don't expect gas-operated rifles to tolerate that extreme type of variation, yet we seem to want it out of a shotgun. The economic reality of the vulgar display of poverty displayed by many shotgunners today has had a vivid affect on product offerings. Obsessing over one hundred dollars over a shotgun that can last many lifetimes, and retains a goodly measure of its original acquisition cost is false, bizarre economy. In terms of the cost of 100,000 rounds through one of my B-80's, it is hard to consider what I paid for that gun to even begin to register. Yet, that is the "respect" many shooters today approach their new purchases with. As a result, hand work is minimized, surfaces that do no absolutely require polishing or finishing are not, and every last cent of tooling life is squeezed out of the manufacturing process. It is for this reason that the jobbed-out parts go to the lowest bidder, and factory triggers and choke tubes can be easily improved upon. Few will pay a few extra dollars for better quality choke tubes, much less a hundred dollars retail for hand-tuned triggers, so our worship of frugality has given us what we have asked for. Nevertheless, today's gas-operated shotgun is better than ever; with (of current product) the Browning Gold / Winchester SX2 action the easy winner. The Beretta 3901 (formerly the A390) follows, particularly if you do your own tuning with a Rich Cole spring kit. The gas operated shotgun is the state of the art. Think of all you've heard about "kick" and recoil. If you aren't shooting a gas gun, you can forget the rest. Think of all the problems and concern about barrel regulation; with one barrel, the problems of pattern convergence don't exist. Want that third dove or pheasant with confidence? That third shot comes in handy. Ever fumble breaking open a break-action in a duck-blind? Gas autos don't need to be broken open to use them. What about a quick shot with an empty gun? Browning's speed-loading, as found on the A-5, B2000, is available on the Gold, and more handy in the field than you might imagine. Shotgun fit is so very critical, yet it is a rare shotgun that fits all of us perfectly. Shim adjustable semi-auto's are a huge help. With that O/U, it may require re-inletting or stock bending. Ever had a stock bent? Most don't bother. Most don't bother patterning their guns that have a single barrel, much less double guns. One barrel makes things a whole lot easier. Style, personal preference, fashion statements, and the like will always be a factor to some extent in what you care to enjoy shotgunning sports with. Until you've gone the gas gun route, though, you'll never know what you've been missing. |
Copyright 2006 by Randy Wakeman. All rights reserved.
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