The Benelli Vinci "Inline" Autoloading Shotgun Action: An In-depth Look The massively hyped Benelli Vinci is not what I thought, likely not what you think and not as advertised. I am generally not inclined to discuss a product at this length unless there is something remarkable about it. There is with the Vinci, but not what it seems. Benelli Advertising The tested 26 inch Benelli Vinci weighs 7.1 pounds. Its action, a delayed-blowback recoil action, produces a sharp recoil pulse consistent with any 7.1 pound fixed breech gun and is not comparable to gas operated actions. In fact, if the Vinci did not produce significant rearward movement, it would not work. Its floating bolt body action requires substantial rearward movement of the rest of the gun to function. If Benelli wants a gun that has 72 percent less recoil, we can help. All they have to is make a gun that weighs 72 percent more and that little problem is solved. Benelli states: "Advanced ergonomics assure fluid gun movement. Combine that with the ComforTech™ Plus recoil reduction system and Benelli puts in your hands the world’s softest-kicking shotgun." There is nothing ambiguous about “the world’s softest kicking” statement. There is also nothing truthful about it, either. If we want the world’s softest-kicking shotgun, a good place to look is for the world’s heaviest shotgun. I suspect we will find the softest-kicking shotgun in very close proximity. Autoloading Shotgun Designs and Pitfalls Let’s get to the really important stuff, semi-auto shotgun design. With most all autoloading shotguns, from the Browning A-5, Remington 1100, Beretta 300 series, SKB 900s and through the present day we have a lurking issue, the mainspring in a tube that resides in the buttstock that closes the bolt and finishes cycling the action. The term “out of sight, out of mind” applies. Many fifty year-old A-5’s have mainsprings that have never seen the light of day. Competition shooters know that it is a good idea to replace that spring at regular intervals, every 5000 rounds or so, as the spring weakens with time and use. The tube that houses it often becomes a respository for powder residue, coagulated oil, grease and other interesting materials. Aside from spring-set, the spring itself is prone to rusting. The spring itself is often indequate to properly regulate bolt speed. This mainspring in semi-autos is an Achille’s heel of sorts. Hard to monitor, not easy to access in the field and no precise or easy way to measure its wear. Non-compensating actions (A300 Beretta, Remington 1100) increase bolt speed in concert with gas flow through the ports. That mainspring must be a compromise, light enough to cycle target loads, yet strong enough to try to protect the gun from baby magnums and similar. It’s not an easy task and with heavy loads the gun tends to beat itself to death. It does get a lot of help from gas sytems that do compensate for gas flow (390, 391, Browning “Active Valve”), but these systems also have their limits. None compensate for mainspring weakening. As testimony to this, we can see the bolt buffers added to the old Winchester Super-X Model 1 and on several other models, including the Beretta 391. In the case of early production of the SX-1 and the 391, the bolt buffer itself caused its fair share of problems. It would be an overstatement to say that the pinned link at the back of the bolt, stock-based mainspring and mainspring tube doesn’t work, as it certainly does. It is hard to monitor, though, and often ignored as a result. The Vinci does away with the mainspring tube, spring and vertically moving bolt link in one fell swoop. Everything is self-contained in the barrel, so all of the added complications of tube, spring, link and sacrificial parts (such as bolt recoil buffers) are taken out of the equation. At the same time, it frees up stock design parameters, so the stock can be whatever is desired without having to accommodate mainsprings and mainspring tubes. This is the “in-line action” of the Vinci and though it isn’t the primary focus of marketing, it probably should be. The Vinci’s inline barreled action is an improvement. The Vinci inline barreled action also takes other negatives out of the equation. Welding or brazing things to the center of a barrel can produce all kinds of problems and has done just that. All the goodies that we enthusiastically braze, solder, or sometimes glue on to shotgun barrels don’t help accuracy or consistency one bit. We don’t think about accuracy in shotguns very often, but we probably should. Bend a magazine tube on an A-5, you can have point of impact problems. With the barrel ring riding up and down the magazine tube on an A-5, it is easy to see this. Remington 1100’s sometimes have point of impact problems, as my recently tested Sporting 20 did. The culprit was a barrel ring brazed to the barrel out of alignment, easy enough to do. There is no such hanger tacked on the to Vinci barreled action. Here, the barrel is essentially the gun. Cranking down a forearm nut threaded to a magazine tube extension creates problems. Barrels heat-up rapidly when fired and they grow in length accordingly. This can result in point-of-impact shifts. A known issue, this is why the Beretta 391 has a ridiculously over-engineered forearm nut consisting of seven parts and is itself spring-loaded. It is intended to allow for barrel growth without bending the barrel. We still have a forearm nut that can seize onto the shaft and yet another spring we can’t see inside the nut that can rustlock itself into non-working mode. Can’t happen with a Vinci, these components don’t exist in its inline action. Other issues appear when you shove a barrel into a receiver. For example, reciever cracking was an issue with heavy use or heavy loads in Remington's first gas autoloader, the Model 58. The inletting was changed on later models to address this. With a self-contained inline action, the stress and vibration that would normally be injected into the rest of the receiver and its parts, often made out of dissimiliar metals, is largely eliminated. The forearm cap prevalant on semi-auto shotguns creates all kinds of issues itself. In some models, there is very little purchase to secure it, with the possibility of the barrel loosening at the wrong time. Flipside, if not tightened properly (and floated) you get cracked forearms. In other designs, they tend to weld themselves on, so some shooters end up looking for a pipe wrench to get their forearm nut off. Beretta goes to the extent of suppling a red plastic bushing shipped with current 391 models to prevent issues when the shotgun is taken down and cased. All of this is necessary, of course, as with no magazine cap your gun comes apart. A forearm cap and barrel ring does not compare favorably with the more robust construction of threaded barrels and recievers. This is far from the end of potential issues, it is just the beginning. Most barrels are sloppily fitted to receivers in semi-auto shotguns. It is a slip-fit, of course, not an interference fit. Slide a barrel into the receiver of most semi-autos and twist it by hand. It is easy to discern what a loosey-goosey fit it has. Not only does the barrel not properly interface with the reciever, but only a section of the barrel normally enters it, the “barrel extension.” Some designs are better than others, of course. When a slip fit barrel goes into a reciever, we have all kinds of vibration and stress inflicted on that reciever. The barrel wear is easy to see after a few cases of shells; you can see the external rubbing and scraping where the barrel is forced rearward upon ignition. The Browning A-5 (and its long-recoil action offspring) takes advantage of this to cycle the gun. There are things we can do to help delay problems, like lightly greasing barrel extensions before assembly of the gun. Nevertheless, in many semi-autos we are continually pounding a steel barrel into a comparatively soft aluminum hole. Steel tends to win this encounter over time. The Vinci eliminates all this; no more slip fits, no more vibration and stress. Perhaps some of folks at Benelli disagree, but as far as I’m concerned a quick release buttstock or an improved recoil pad is all sub-text; trivia compared to what the inline action accomplishes. The inline barrel action makes the other Benelli models obsolete. That’s the intriging and exciting aspect of the Vinci, as far as I’m concerned. The rest is just frosting on the inline cake. Some of it is tasty frosting, though. Much ado is made about the “modularity” of the Vinci. For the reasons stated, the in-line action is by far its most valuable feature. The quick-removable buttstock means little, as the inline action eliminates the need to inspect, repair, or replace any components inside the buttstock. There are no wearing parts inside. The ability to remove the “lower,” which contains the trigger group is of value, though. A push of a button and inspection and maintainence are just seconds away. Autoloading Cycle Rate Cycle rate is touted as important. A fast cycling shotgun is supposed to be good. Is it? Beretta Xtrema2 advertising spots show Tim Bradley firing 12 rounds out of an Extrema2 in 1.73 seconds. Tom Knapp shot a then world record with a factory Benelli M2 in 2004, breaking ten hand-thrown clays with ten shots in about 2.2 seconds. That record didn’t last for long, as on July 6, 2005, it was eleven clay targets hand thrown, individually shot, from the shoulder and without assistance with a Winchester SX3 by Patrick Flanigan. Patrick Flanigan cracks off 12 rounds with a Winchester SX3 in 1.442 seconds in another widely seen spot, clearly, quite a bit faster than the Xtrema2 managed. I’ve met Tom; he’s quite a gentleman and a fine spokesperson. I know Patrick, like him, and consider him a friend. The point of all this is that prominent gun companies have a sad record of paying for ads that contain meaningless “information.” There is no such thing as a slow autoloading shotgun. In fact, many of todays models are slower than the original, John Browning’s A-5. In all of my years of shooting, I’ve never been forced to wait and twiddle my thumbs while any brand or model of autoloading bolt closes to take a second bird. This vaporware issue never did exist. I note this solely because there are salient differences in action types, but cyclic rate is not one of them, unless you are running a marketing campaign and have nothing of substance to talk about. The Mystery of Shotgun Recoil No through discussion of a shotgun is complete, it seems, without the omnipresent mystery of recoil. Since recoil is brought to the forefront both by manufacturers claims and shooters, let us consider a few facts. In W.W. Greener’s The Gun & Its Development, ninth Edition, page 686, Mr. Greener discusses the “12 bore Game Gun.” Greener writes that the best all-round gun for sporting purposes is a 12 bore double weighing about seven pounds. While they can be no really wrong answer, Greener’s notion is as on target today as it was one hundred years ago, if you stick to the light, low brass field loads for which British game guns were designed. One way to look at the shootability aspect of the Vinci is practical, hunting level shooting comfort and here the Vinci's “ComforTech II” stock comes into play. At the risk of sounding too esoteric, the shotgun that works best is a system. No one facet is omnipotent; it is the synergy of all the factors that makes wingshooting effortless that is the goal, or should be. Choke tube makers might like to you to think it is all in the choke, recoil pad sellers might tout it is all in the pad, those who provide aftermarket forcing cone work and barrel porting might like you to believe that is what really counts. They are all wrong. As a practical matter, there are three primary factors to consider in actual recoil. The first and foremost is gun weight. A 12 pound gun is going to have half the recoil of a six pound gun, assuming the same load and action type. Beyond that, it is shot payload mass (including wad and powder) and muzzle velocity. That’s all there is. The recoil pulse is very brief in a 12 gauge shotgun. The shotgun “recoil event” was recently studied at the Department of Mechanical Engineering, University of Texas at Austin. The duration of shotgun recoil was found be about ten milliseconds. That is 1/100th of a second. It is a far faster pulse that most of us realize. That 1/100th of a second that fascinates us is roughly equivalent to two flaps of a honeybee’s wing. The blink of a human eye takes thirty to forty times longer than the shotgun recoil pulse. Therefore, the recoil we are concerned about doesn’t just happen in the blink of an eye, it happens 35 or 40 times quicker than that. Recoil happens so fast we cannot possibly react to it directly, nor is the human body equipped to measure it with any precision. It happens far too fast for our senses to appreciate in progress. If you consider the actual 10ms speed of the entire recoil event, you will quickly conclude that some of the most famously championed features are false on their respective faces. Soft recoil powders, soft recoil wads, soft recoil forcing cones and so on are un-verifiable. To arrive at shooting comfort, we have to dig deeper. Feisty Elmer Keith used to say, “It’s all in your head.” I found many things in Elmer Keith’s head hard to understand; perhaps he packed the residual results of heavy recoil up there. Fixed breech guns do nothing to address recoil. They are the hardest kicking actions around and always will be. That does not mean they are unusable, of course, it is just a fact about the action. “Attenuate” is one of those three dollar words tagged onto recoil. It originally meant, “To make thin,” or reduce. Gas-operated shotguns subjectively kick less, because they transmit the rearward thrust of the shotgun in fragmented components rather than the single rearward movement of a fixed breech gun. The total amount of recoil energy is the same, but it occurs over a longer time at a lower amplitude. In a gas gun, something often overlooked is the reverse recoil. The gas piston, action bar and breech are fired in reverse, right back at your shoulder. It is a good thing, a very good thing, as we now have forward thrust added to a section of the rearward thrust event we call recoil. The mass and velocity of the reverse recoil components serve to counteract our conventional kick. Though significant, it is limited by a couple of things. Our reverse recoil event cannot be initiated until we have gas flow through barrel ports and the reverse recoil event ends when the gas induced motion stops (when the breech bolt is fully rearward). The net effect is to reduce the peak skin pressure by flattening out the skin pressure trace; it lengthens the overall recoil event. It does not stretch out the recoil event by much, but it does not have to. Just a one millisecond elongation of the skin pressure curve against your shoulder flattens the peak pressure exerted against the skin. No such peak skin pressure reduction is possible with a pump, O/U or SxS; nor is it possible with a delayed-blowback action such as the Vinci. That does not tell the full story, however. The notion of recoil absorption merits further mention. We have astonishingly dishonest advertising in this area. A particularly puzzling claim is by Remington, about their “Supercell” recoil pad. Remington advertises: “Ten years of rigorous R&D has produced a recoil pad far superior to anything the world has seen before. So effective in fact, our Model 870 pump shotgun now produces 54% less recoil than competing autoloaders with their factory pads. This remarkable level of hoax defies both explanation and common sense. To search for the real story, my research led straight to the U.S. Patent Office. U.S. Patent 6,305,115 of October 23, 2001, by Todd B. Cook was assigned to R.A. Brands, 870 Remington Dr., Madison, NC. The testing included as part of this patent, using Kistler dynamic load cells and a high-resolution accelerometer, is quite revealing. These gel pads of various durometers were precisely measured using a Remington 870 pump and both Nitro 27 target loads and heavier turkey loads. The “super” pads reduced recoil force by 19% with target loads and just 6% with turkey loads. Comparisons were done against both solid rubber and vented pads and the differences were subtle. For example, during qualitative testing, a group of 200-pound shooters actually found the vented rubber pad to be superior to two out of the three “super” gel pads. It appears that the claim of “54% less recoil” fails in every way and especially when compared to autoloaders. The maximum recoil reduction shown was 19%. The apparent preferred rendition of the pad, using 90 Shore Hardness (00) material, managed roughly 15% reduction against a generic rubber vented pad with trap loads and less than a 2% reduction with turkey loads. The people at Remington's ad agency should be ashamed of themselves. Shooting comfort is comprised of many things, including isolating the sportsman from unwanted vibration. No shotgun action is immune from this, not even heavier gas-operated autos that are generally softer shooting than the Vinci. A friend of mine in the industry related his high volume shooting experience in Argentina with a popular gas auto. A right-handed shooter, his left hand became numb after a couple days to the point of affecting the trip. As it turned out, the culprit was the gas action itself. Drive a gas piston at a high rate of acceleration and high speed down the inside of an autoloading forearm and vibration may result. In this case, the vibration was more than sufficient to cause pain and discomfort that was both surprising and unwanted, Comparative Testing I recently spent several days comparing recoil from a field perspective. The "control" shotgun chosen to compare against the 26 inch barreled, autoloading Vinci was a fixed breech Browning Cynergy Euro Field over/under with a 28 inch barrel. The Cynergy was not selected because it is a harsh shooting shotgun. To the contrary, the 7-1/2 pound “Influx” pad equipped Cynergy is one of the softest shooting O/U’s I have ever tested in its weight class. All of our shooters felt that the Cynergy is quite comfortable to shoot with 1-1/8 oz. 1230 fps loads. With the Cynergy as our control unit, we began a long series of tests versus the seven pound Vinci. While the Cynergy was and is a comfortable shooting shotgun with B&P F2 Legend 1-1/8 oz. shells, it became clear that the Vinci was, subjectively, a softer shooting shotgun, despite its half-pound lighter weight. Not by leaps and bounds, not by a huge amount, but without question a little bit softer shooting. The next step was to change the intensity of our test loads, this time to 1-1/4 oz. Federal Hi-Power 1330 fps loads. We used the same cycle of comparative testing: one shot from a gun, switch and repeat. Then two shots, switch, and repeat. Then six shots, switch, and repeat. Now, the comfort level changed dramatically. The Cynergy had a pronounced jolt, while the Vinci’s recoil increased by a much smaller amount by comparison. The Vinci was a creampuff compared to the Cynergy. Next up were 1-3/8 oz. Fiocchi Golden Pheasant loads. At this point, the Cynergy recoil was up to the point where repetitive shots were no fun at all. The jolting becoming invasive enough where none of our test shooters made it through a full box of Golden Pheasants. Recoil increased somewhat with the Vinci, but still a comparatively small increase compared to the previous batch of 1-1/4 oz. Federals. It was fun breaking clays a foot off the ground at eighty yards, though. The final stop was a box of vintage Winchester Super-X Mark V 2-3/4 inch Magnums, featuring the “new” (for 1962, that is) Mark V shot collar and 1-1/2 oz. of #4 shot. Our shooters declined to shoot them out of the Cynergy, already having the benefit of all the recoil they cared to enjoy. There is a reason these shells were still in my arsenal. This was the load that bent the mainspring tube of a standard-weight Browning A-5 with the first shot. The remaining shells had been in storage ever since. We ran half a dozen rounds through the Vinci with no problems whatsoever. The recoil was uncomfortable, though, so these old Mark V magnums would not be shells we’d want to shoot all day, to be sure. Note that three-inch steel loads actually contain lighter payloads than either the old Mark V or even the Golden Pheasant loads, typically 1-1/8 oz. at 1500 fps or 1-1/4 oz. at 1400 fps and have little more recoil than a traditional 1-1/4 oz., 1330 fps high brass, lead shot load, such as the Federal Hi-Power loads included in this test. From our analysis, we discovered that, by comparison, the autoloading Vinci became increasingly more comfortable and more shootable as the intensity of the loads increased. Another way of phrasing it, in this case a bit ironically, the Vinci has far more synergy than the fixed breech Cynergy O/U. The Vinci’s ability to dampen the recoil pulse correlates positively with increasing recoil. Summary At the beginning of this long missive I mentioned that the Benelli Vinci is not what I thought, likely not what you think and not as advertised. I hope that the reasons for those comments are a clearer now. Mechanically, the Vinci may be the most significant advance in autoloading hunting shotgun actions in the last fifty years. Its action design is superior to that of many fine autoloaders, including Benelli’s own product. The Vinci accomplishes this not by living up to its hyperbole, but in several ways that address balanced hunting performance and reliability. Forearm nut issues are gone. Barrel ring and barrel hangar issues are gone. Unwanted stress to the receiver and receiver wear are gone. Barrel extension issues are gone. Stress on the magazine tube is gone. Forearm vibration inflicted on the shooter is gone. Cracked gas pistons, fractured struts and broken breechblock links are gone, as are rusty mainsprings and bent mainspring tubes. Balance issues and rattles associated with long under barrel linkages, rods and action parts are also gone. The inline action, integrated with the barrel itself, does all this. The Benelli stock system introduced on the Vinci is also functionally significant. As our comparative testing with the Cynergy showed, the current “ComforTech II” stock is an advance. The recoil pad and its softer durometer have been changed to better compliment the range of payloads normally used in hunting: 1-1/8 oz. to 1-3/8 oz. The larger and softer chevron pieces integrated with the stock may do some good; of note in particular are the larger sections appearing on top near the butt and below near the receiver. For too long the ground-up garbage can lids presented as “synthetic techno-polymers” have done nothing functional in shotgun stocks. The Vinci stock and recoil pad are intended to combine dynamically to adjust to load intensity. The Vinci is not the fastest action. The Vinci has more speed than you can use, though, an important distinction. It is not the softest shooting shotgun, either. That characteristic will likely go to a ponderous 14 pound trap gun, not to a 7 pound field gun. More to the point, it is exceedingly comfortable to shoot for its weight and gets even more impressive as the payloads and velocities are upped beyond light clay target loads. This again substantiates the field prowess of the package. It is an inspired mechanical design, presumably destined to be amplified and further explored. I would not be at all surprised if the Vinci gave birth to an entirely new line of shotguns using this platform as a springboard; it well should. I am ready to call the Vinci a great shotgun design. Its action eliminates the weak spots of other autoloaders, apparently without adding new issues. |
Copyright 2009, 2014 by Randy Wakeman. All rights reserved.
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