Thank you Shooter13. These photos should finish this project. From the bottom up are barrels from the 1903, a 1947, a 1924 16gauge, and a 1908 Remington Autoloading Shotgun (pre Model 11). All have the notch in the barrel extension except the one from the first year.
Just heard from someone who owns an A5 from 1905. His barrel extension is identical to the first year's.
A poster on ShotgunWorld mentioned that the stocks are either drilled out or hollowed out behind the butt plate, and this pre-dates the Sweet Sixteen which debuted in 1936. A look behind mine shows... Nothing. Not even a hole for access to the action spring that I expected.
A few more shots of the barrel. Provisional Proofs and barrel diameters--one at the muzzle and one 8.6" from the breech. The very early guns had the rings mounted on a ramp. Underside of the extension. Still haven't discovered the reason the "notch" was added on later guns.
Well, what have I learned? Mostly that John Browning's Automatic Shotgun survived 95 years of production with few mechanical changes. And those few changes appear to have been made more to ease manufacture than to improve the product. I'm sure that most of the parts from a gun from the '50s or '60s would interchange.
A last word on chamber length. The S/V book says all 12 gauge guns had 70mm (2 3/4") chambers throughout production. Martin said US guns did, but European guns had 65mm, at least in the early years. Later guns were marked, but not in 1903. My high tech chamber checker (a cut down credit card) stopped 5mm short of where it did in a 70mm marked barrel. So, 65mm, right? But some 3" of the credit card was disappearing down the 2 3/4" chamber, suggesting there was more room than advertised. A 12 gauge hull, stuffed with paper to keep the crimp straight, easily went fully into the chamber. So, what the heck, I shot 2 boxes of Rios tonight. Not a single malfunction. As far as I'm concerned, it's 2 3/4" gun.
Just when I thought I was done....I learned a little more. I found this post by Martin: http://www.shotgunworld.com/bbs/viewtop ... 1&start=20 On page 2 there are pictures and diagrams of early vs. later barrel extensions and locking blocks. It turns out that the "notch" on later barrels is there to accommodate a "tail" on the locking block when in the unlocked position.
I'm going to change the thrust of this post a little. I've run out of mechanical differences but not pictures, so I thought I'd explain some of the markings and how they've changed. There are better sources, most notably the "S/V" book, available here: http://www.fn-browning.com/Browning Auto-5 Shotguns.htm This picture shows the "Cockerill Steel" marking on the 1903 barrels. This was the finest steel available at the time. This was changed to "Special Steel" on later guns imported to the US, and "Acier Special" on World Market guns.
More barrel pictures. "BROWNING AUTOMATIC ARMS Co OGDEN UTAH USA" was, to my knowledge, only used on the first run of 10,000 guns. According to S/V, less than 3000 of these were imported to the United States when importation was halted due to high import tariffs. When imports resumed in 1923, the address had changed slightly. The following is from a 1924 16 gauge.
Notice on the barrel the word "CHOKE" is stamped but there's no mention of how much. I don't know when the modern terms were coined, but on the bottom of the barrel two diameters are stamped. The difference is the constriction which in this case corresponds to "Full".
In many of the pictures a Star/J is visible. This is the Controller's Mark, the government official in charge of the proof testing. A list of the controllers and their marks is available, but unfortunately only goes back to 1911. The list includes the various proof marks and date codes that were introduced in 1922. http://damascus-barrels.com/Belgian_All_Proofmarks.html
See that proof mark that looked like a statue? That's "Le Perron" applied when the breeching system is tested. It's marked on the bolt, receiver, barrel, extension, and--I never noticed this before--the locking block. Not sure if that's unique to the first guns.
Earlier I mentioned that the front sight had been replaced with a fiber optic. I replaced that with a plain bead, but because of the Auto-5's high receiver it wasn't really functional. I wanted to add the sight ramp, but didn't want to solder it to the barrel. A friend machined a screw to match the interior of the ramp, then cut the shank to size and filed it to match the curvature of the bore. With no permanent change to the gun, here are the results:
I'm glad I didn't permenantly attach that sight ramp. There is some confusion about whether or not the very first Auto-5 s had the sight ramp. Recently someone found a pristine 1903 gun--and it has no ramp.
I found a very similar gun serial 62xx at a gun shop. I'm wondering what the value may be. I figured that with a serial number below 10,000 it would be a first year. I know the fore end has been replaced. The butt plate is not horn but, some sort of rubber/leather material. It has the safety inside the trigger guard and a straight stock.
The gun you found was made in 1904, but it's still a First Year gun as deliveries didn't start until September of 1903. The first buttplates weren't horn but Vulcanite Rubber. Few have survived, so if original that's a big plus. Too bad about the forearm. Original forearms may be as rare as original buttplates. Rare as First Year Auto-5s are, there doesn't seem to be a large market for them. Condition is everything when determining the value of a gun that they made millions of, and the early guns are lumped in with the rest. I saw one on gunbroker get no bids over several auctions. The seller had a $1000 minimum. Here's one similar to the one you found for $400: http://forums.accuratereloading.com/eve/forums/a/tpc/f/5451078981/m/7431008802 To me, a First Year Auto-5 is a priceless piece of history. But right now they can be had for a minimum investment.
