The Shotgun Autoloading Inertia Action of Perpetual Motion and Mystery
Few things have caused more
discussion and more confusion than the so-called “Inertia” or
inertial action as currently used on Benelli brand shotguns and the new
Browning A5. Benelli for example, has called it simple because an object
at rest tends to remain at rest. With that line of thinking, inertia shotguns
don't work at all, the just like to rest a while. Things being at rest
wasn't Newton's First Law, though, it was equally about objects moving
and objects at rest: “Law I: Every body persists in its state of
being at rest or of moving uniformly straight forward, except insofar
as it is compelled to change its state by force impressed.”
Another notion that is bizarre as described is that the inertia autoloader waits until barrel pressures drop to a safe level before it starts to eject a hull. There is no pressure sensor on an inertia action, no computer chip that cares about pressure. Bruno Civolani invented this action, which was purchased by the Benelli brothers in 1967, apparently first produced in 1969. Ironically, it was referred to as kinematic action back then, the 'new' name for it in the just-released Browning A5.
What is actually is, according to the inventor and the patent, is a “Gun with a floating breech bolt.” Benelli lasted until the year 2000, when it was swallowed by the Beretta group which now includes Beretta USA, Franchi, SAKO, Stoeger, Tikka, Uberti, and Burris Optics. With the patents expired, similar actions are offered not only by the Beretta family of companies such as Stoeger and Franchi, but also by Caesar Guerini and the most recent to appear, the Browning A5. There is both good and bad about the Civolani action, but the facts are nothing like what wacky ad copy has portrayed.
Browning has had an ad-copy disdain for the Civolani action, primarily because they didn't offer one. Now, they do. The Remington brand, making their first alloy autoloader which is a transparent copy of the Benelli M4 gas autoloader, is claiming that “Inertia Died,” apparently in favor of ugly, overweight plastic shotguns with heavy triggers.
Yet, Benelli has no problem overstating their recoil reduction, as most shotgun brands do. Like most anything else, there are advantages and disadvantages. I'll list them as best I can, starting with the disadvantages of the floating bolt Civolani action.
DISADVANTAGES
1) Cycle Speed
While it is an area almost not worth talking about, marketing folks don't see it that way. The Civolani action is slower than the long-recoil Browning Automatic Five, both are marginally faster than the “turtle slow” Remington 1100. The fastest cycling actions are either the Browning Silver / SX3, the Browning Maxus, or the Beretta A400 depending on who you want to believe. The best thing to believe is that the differences don't matter at all.
2) More Recoil
Recoil has more to do with gun weight and shell intensity than anything else. There is nothing about the Civolani action that reduces recoil. It is just like any other fixed breech gun; if recoil was all there was we would all be shooting extremely heavy gas guns and no one would dare shoot an O/U or pump. The felt recoil reduction of gas guns has been overstated. If just being a gas shotgun was all it took, why would you have to attach a pogo-stick to an A400 (Kick-Off) to make it comfy, and why would the overly plump Versa-Max need a space-age recoil-pad that is so thick? Gas guns do tend to feel softer, but not nearly enough to ignore shell intensity, gun weight, and stock fit.
3) Less Shell variety Capability
Some gas guns are better at handling the full spectrum of loads than their kinematic counterparts. That assumes that the gas gun is clean, for they all get sluggish given dirty loads and enough time. They have improved, though, substantially from the 1963-introduced 1100 Remington that may get noticeably slow after 300 dirty shells or so. Also, there must be rearward movement of the Civolani gun to operate. Add a lot of weight, the sliding split bolt can no longer adequately compress the 'inertia' spring.
ADVANTAGES
1) Less Maintenance
No question, with no gas system to clean, the Civolani action requires less cleaning. No gas pistons to break, no gas linkages, no wear to a magazine tube.
2) Lighter weight
Twenty gauge gas guns (B-80 alloy, Beretta 303, Browning Gold / Silver) are 6-1/4 lbs., or so. My M2 is 6 lbs. on the nose, same with the Franchi Affinity. The weight difference is more pronounced in 12 gauge, for the most part. A Versa-Max is 7-3/4 to 8 lbs., the lighter Maxus is under 7 lbs., but the new A5 is just over 6-1/2 lbs. The Benelli Ultra-Light I reviewed came in at 6 lbs., 3 ounces.
The most reliable shotgun is almost impossible not to buy, according to the ads anyway. But, it is more clear according Hayes & Hayes Outfitters: the Benelli Montefeltro and the Beretta 390 are the most durable shotguns around, as mentioned in http://randywakeman.com/Most_Reliable_Autoloading_Shotgun.htm .
FINALLY
To paraphrase Ronald Reagan, the trouble with our gun marketing friends is not that they are ignorant, but that they know so much that isn't so. With similar gun weights, gas-operated shotguns are softer-shooting. However, with appropriate loads and appropriate clothing it wasn't any great issue a century ago and it isn't today. It is less of an issue for typical hunting applications than for aggressive target shooting. There are far more truly crummy gas-operated autoloaders out there than Civolani guns, only because there are far more gas autoloaders out there. The Stoeger brand has proved that a kinematic action doesn't really have to be a good thing. Despite the wondrous handling of the Benelli Ultra Light, that's the gun that proved to me that kinematic guns can be too light and too uncomfortable to shoot with the loads I want to use.
The most reliable repeater action has always been the slide-action, for you don't have to rely on it to close itself. We have to rely on ourselves, and sometimes we don't exactly relish the idea. There is no brand of gun immune from putting out a real clunker, though some seem far more adept at it than others. We are all better off buying the actual product, not the printing on the box.
Copyright 2012 by Randy Wakeman. All Rights Reserved.
