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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 as far as I'm concerned.
Bob Brister described the felt recoil dampening extremely well, in his
must-have "Shotgunning: Art & Science," using the
Remington 1100 as his exemplar. The recoil reduction industry is a huge
one, with some rather strained approaches touting tangible benefit. My
shoulder tells me 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-- 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-- 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 ga. 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 are, 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 - 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 perfectly-but, with Rich Cole springs
you could easily tune a specific A390 to a specific specific load, getting
reliable 10 - 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 - 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 break, and 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 use perfectly. Shim adjustable semi-auto's are a huge help-with that
O/U, it may be 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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