'The Impossible Shotgun' by Floating Chamber

'Floating Chamber' outlines the history of this short-recoil old-timer - a 1960s vintage Winchester Model 59 semi-automatic. The gun with a separate 'floating chamber', a 'fibre-glass' barrel and the first ever screw-in chokes!

Pick up any modern semi-automatic today and it will be a gas or inertia-operated, sweet shooting gun with a 'fixed' barrel. Many of you younger shooters out there would not expect anything different, but, starting in the early 1900s with the Browning-designs, all semi-autos were 'long recoil' and would remain so for nearly fifty years. In these guns the bolt and barrel recoiled together for more than three inches, against a heavy operating spring which was coiled around the magazine tube. This system caused the 'double-shuffle' sensation that many shooters found distracting and the mechanism had to be adjusted for light and heavy loads. Also, these guns would often refuse to cycle if not pulled tight into the shoulder. In 1954, a revolutionary new design changed, forever, the way self-loaders operated. This newcomer was the World's first semi-automatic shotgun with a fixed barrel - and it needed no adjustment for light and heavy loads. It functioned using what has become known as the 'short-recoil' system - a 'stepping-stone', you could say, between long-recoil and the gas system. However, this gun enjoyed only limited success - because hot on its heels were the gas-operated guns similar to those we know today. The first one of these being the J.C. Higgins Model 60, in 1955, followed by the Remington 'Sportsman-58' in 1956.

An Impossible Task?

In 1934, the team at Winchester began looking for a system that would enable a self-loading shotgun to function with a fixed barrel. It seemed an impossible task. After many trials and failures with external 'inertia weights', the idea of using the weights inside the stock looked promising but the development was interrupted by World War II and by the production of the US .30 cal. Carbine. The work continued after the war with David Marshall 'Carbine' Williams joining the design team at Winchester. Williams, a North Carolina 'moonshiner', had invented and patented several 'actuators' while serving a thirty-year prison sentence. (He was blamed for the death of a Deputy Sheriff, following a raid on an illegal still). He was then twenty years old. One of his inventions, the floating chamber, an actuator which enabled the .45 Colt 1911 automatic pistol and the .30 cal Browning machine-gun to operate on .22 rimfire ammunition, saved the US Government millions of dollars in training. For these inventions and, of course, his .30cal M1 Carbine, Williams was pardoned after serving only nine years of his sentence. It was a larger version of this chamber that was to become the operating heart of the new model.


Marsh Williams spoke of the day he joined the team. (From a filmed interview in 1962)
'...I could plainly see when I tackled this job, what a job it must've been for somebody to even try. It was the hardest design job I ever tried in my life - looked like nothin' would get right about it - everything was wrong. The only thing that didn't give any trouble to start with was my moveable chamber; it would always operate perfectly...'

With all the frustration from false starts and obstacles, development was again held up when the ATTF (now the BATF) contacted Williams and declared the shotgun illegal in the drawing stage! Again, in Williams' own words:
'Well, before I got it introduced to Winchester 'good', the Alcohol, Tobacco, Tax and Firearms people descended on me, claiming that it was, because of the floating chamber, a sawed-off shotgun that required registration under the Machine Gun acts. We had one hell of a discussion about this, but eventually, when they understood the principle, they allowed this shotgun to go into production.'

The Floating Chamber

The floating chamber, the gizmo that operates this gun, looking, at first glance, like a cut-away Webley and Scott .410 adapter, fits loosely inside the barrel. When the gun is fired, the chamber and bolt, which are locked together, recoil about a tenth of an inch before coming into contact with a shoulder in the receiver. This movement is a short, sharp and violent one, hence, 'short-recoil'. After the bolt and chamber come to a halt, this movement is communicated to a sliding inertia weight in the stock by means of a pin and link and this weight continues to the rear, taking with it the slides. After travelling a short distance in the bolt-slot, the link-pin encounters an incline in the slot which tilts the bolt downwards and unlocks it from the chamber. This delaying-action distance allows the shot to get clear of the barrel by about three feet before the unlocking takes place, so there is no loss in velocity. It also spreads the recoil over a longer period of time and is not so 'abrupt' as that of any auto of the period.

During 1951, the first of this new breed of semi-autos, The Winchester Model 50, was being secretly tested. The first gun was fired 58 000 times with just the breaking of a small spring. The next 25 production guns were each fired 10 000 times, again, only minor malfunctions occurred. During the next three years, over ten million cartridges would be used in testing. 'Oscillograph' readings also showed that in a recoil comparison test with a long recoil gun, using the same ammunition, the recoil of a Model 50 was found to be more than twenty percent less. It looked like Winchester had a winner, but, another three years were to elapse before the launch of the Model 50. Later, in an attempt to lighten the gun, a variation called the 'Featherweight 50' was introduced. This had a steel barrel like the M50 but the receiver and trigger assembly were aluminium. In 1960, Winchester was to go one step further with a third model.

The floating chamber of the Model 50/59 shotgun which takes the principal breech pressure,
with a loaded cartridge below showing how far the shell goes inside.

The Model 59 with the barrel removed showing the chamber
in place with the two-shot magazine below it.

'Glass' barrel Model 59

Born in 1959, and launched in 1960, this model was fitted with what Winchester termed:
'the greatest advance in over 600 years of gun-making: Win-Lite: the incredible glass fiber barrel. This shotgun is Winchester's Model 59. Its weatherproof Win-Lite barrel is made with 500 miles (yes, the claim was 500 miles) of glass fiber fused and bonded to an extremely thin tube creating a barrel much stronger than steel and at nearly half the weight of conventional barrels. The inscribed receiver is aluminum. It will never rust. The Model 59 weighs 61/2 pounds. It is the strongest, fastest shooting lightweight automatic ever made.'*
* Taken from the advertising literature of the early 1960s, hence American spelling!

Short Production Run

The model described in this article, the Model 59, has another revolutionary feature. The 'glass' barrel has screw-in 'Versalite' chokes - which some critics at the time described as 'unworkable gadgets that would never succeed!' Yes, we can all laugh now! Sadly, the shooting public did not favour the bulky look of the barrel and Marsh Williams himself commented that the steel barrel was 'somewhat more slender and graceful than the glass barrel' - and only 82 085 Model 59s were made. The model 59 in this article is No. 51073 and the Model 50 is No. 65341.

In 1963, slap in the middle of production of the 'glass' 59, Wayne Leek's gas-operated Remington 1100 hit the market and I believe this sounded the death-knell for the Model 50/59. The model 50s are numbered 1000 to 196400 - not a large production at all when compared with the on-going Remington 1100 which reached the million mark in 1972 and exceeded 4 million by 1999 and still going strong.

Significant Following in U.S.

Browse through the American shooting websites and you will find many 'postings' in Model 50/59 forums. The friendly owners of these old guns are keen to help with advice and I have benefited from this on several occasions. There is a significant following in the U.S. especially among those shooters of advanced years, who favour this fast swinging extremely lightweight semi-auto that can be easily carried all day. There is also the nostalgia factor! Indeed, everything is easy about the '59. Being slightly 'butt heavy' the muzzle comes up fast. 'The magazine has a light spring and it is easy to load and unload especially when your fingers are cold.' (Williams' own words.)

The action is fast and there is no being 'put off' the second shot. Recoil from the M59 using 30 gram and heavier loads is noticeable because of its 6 1/2 lb weight, but on the heavier Model 50 it is comparable to a modern gun.

Stripping Down

All that is needed to strip down this gun is a small pointed drift* or twig and a cartridge rim and it comes apart with ease just like a piece of ordnance. (Maybe Winchester had designs on selling a long-magazine or box magazine version to the military?). Apart from the butt-plate screws and the buffer-plug screw, there is only one other and that holds on the fore end. When this is removed, using the rim of a shell, the barrel is turned a quarter-turn clockwise or anti-clockwise and it comes free of its 'interrupted' internal receiver rings. When the barrel is removed, the floating chamber can be removed easily for cleaning by pulling back the cocking-lever about half-way to unlock the bolt. Simple!

*(Example: the carrier spring from the trigger plate can be used as a drift.)

Unlike the modern pressed-metal parts on some of today's 'painted-lady' gas-operated guns, all the parts are made from solid metal stock. The carrier is a chrome vanadium steel forging. The trigger-guard, which is machined from a bar, is easily removed by pushing out one pin. Springs are inexpensive and can be even be fashioned from large safety pins or music wire. They are easily removed and replaced using thumb and finger. The stock and fore end are of American Walnut and nicely chequered. No tacky pressed chequering here!

Test using subsonic loads

At the 2006 Midland Game Fair at Weston Park, a brief discussion with Michael Yardley on loads for semi-autos inspired me to conduct a test using my Models 50 and 59 with five other autos, firing subsonic loads. (It is well known that most self-loaders do not 'like' subsonic loads!). The other guns were a Browning Gold, a Beretta A391, a Browning 2000, a Winchester X-1 and my Remington 1100. The cartridges were taken from the same batch of Lyalvale subsonic (1040fps) 1-oz Fibre to make it a fair test. In brief, the four other guns failed to cycle, returning the spent cases to the chamber after a short movement of the bolt. The Models 50/59 handled the two rounds crisply, leaving the bolt open after the second shot and the hammer cocked. All of the remaining cartridges from the box were then fired through the 50 and 59 by the eager test-shooters, who were amazed at the performance of these old-timers. The floating chamber does work perfectly, just as 'Carbine' said all those years ago!


Certain parts are still available from the U.S. I recently received a bunch of bits that may, in the future be needed - BUT, if you badly dent a 'glass' barrel on a '59, it will have to be scrapped - and, unless you can find one on eBay, you're sunk! Your best bet would be to get a Model 50.

WINCHESTER 'Versalite' chokes - the first screw-in chokes


Compared to the state-of-the-art autos of today, with stone finish, inlays, plastic trigger-guards, synthetic stocks, carbon-fibre receivers and suchlike, the Winchester Model 50/59 looks fifty years old. However, it is a nice piece of gun-making history and was probably the 'bee's knees' during its short life - and it is a joy to shoot it - with light loads!


Take a look at US Patent Number 2,476,232. (Filed 1947) This is the patent granted to Marsh Williams for an 'Inertia Operated Bolt lock'. The drawings show clearly the birth of the Model 50. Now take a look at the US Patent Number 4,604,942. Filed 1984 - the Benelli patent. At the top of the 'References Cited' list is Patent Number 2,476,232 - Williams!

Author's Note: I am indebted to the family of Marsh Williams (His son, David, Daughter in Law, Dorothy) and Marsh's younger brother, Gordon, who is 93 years old this year!

I would also like to thank my friend, Lt. Col. Ross E. Beard, Jnr. (author of 'Carbine - the Story of David Marshall Williams) for his invaluable help. Ross was a close, personal friend of the late 'Carbine'.