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LC Smith 12 bores were 2 & 2/4" chambered right "outta da box"-- but when did: (1) Parker (2) Ithaca (3) AH Fox 12 bores go from 2 & 5/8" to 2 & 3/4" chamberings? A friend has a 1937 Savage Fox Sterlingworth 12, and he swears his Galazan chamber gauge reads 2 & 5/8"??

After Savage bought Fox, all their guns were supposedly chambered 2 3/4". If you sent them back to the factory for other repair work, they'd automatically lengthen the chambers for you, unless you specifically told them not to.

Per my 1936 Abercrombie & Fitch catalog, Parker had switched to 2 3/4" chambers as standard in 12-16-20 by that time. For more exact dates on when companies like Ithaca and Parker switched to the 2 3/4" 12ga as standard, you'd probably need to find someone with catalogs from the respective companies from that era.

However . . . some companies, even when they marked the guns as having 2 3/4" chambers, continued to intentionally short-chamber their guns. The reason: they'd found that the paper case mouth, opening into the forcing cone, provided some protection to the shot on its initial contact with the barrel walls. Thus reducing deformation and resulting in better patterns. But if a gun is factory marked 2 3/4", whether it measures that or not, then it would have been proofed to the higher standards of the 2 3/4" shells versus the old 2 5/8" shells, which were loaded to a lower pressure standard.

FOX CHAMBERS --

The only two A.H. Fox Gun Co. catalogues, that I have seen, that state chamber lengths are the 1913 and 1914. They both state 12-gauge guns are regularly chambered for 2 3/4 - inch shells, 16-gauge 2 9/16 � inch shells and 20-gauge 2 1/2 - inch shells. That being said, virtually every 12-gauge Ansley H. Fox gun made in Philadelphia (other than the HE-Grade Super-Fox) that I've run a chamber gauge in shows about 2 5/8 - inch. The chambers of unmolested 16-gauge guns seem to run about 2 7/16 inch and 20-gauge guns a hair over 2 3/8 inch. A very few graded guns were ordered with longer chambers. Savage began stating chambered for 2 � inch shells in their 1938 Fox catalogues.

All this being said there is a good body of evidence that back in those days chambers were held about 1/8 inch shorter than the shells for which they were intended. In the book The Parker Story, the Remington vintage specification sheets on pages 164 to 169 call for a chamber 1/8-inch shorter than the shell for which it is intended. Also in the 1930's there were a couple of articles in The American Rifleman (July 1936 and March 1938) on the virtue of short chambers.

Also, Askins mentions (Modern Shotguns and Loads, 1929) that for the last 3 years or so the US makers started to hold their chambers shorter since the constriction made when shooting 2-3/4" loads in 2-5/8" chambers was found to improve patterning?!?

ITHACA CHAMBERS -- The last Flues period catalogue (1925) states -- "Unless otherwise ordered Ithaca 28 Gauge and 20 Gauge guns are chambered for the standard 2 1/2 inch shell, 16 Gauge and 12 Gauge for the standard 2 3/4 inch shell and 10 Gauge for the standard 2 7/8 inch shell. Longer chambers are furnished if ordered on new guns without extra charge, but it should be remembered that shells of standard length do not give quite as good results in chambers which are longer than the shells and it should be remembered that extra long shells are more expensive and it is much harder to find a dealer who carries extra long shells in stock." I find that 2 3/4 inch pretty strange in the 16-gauge, because 2 9/16 was the standard 16-gauge shell until WW-II!?! None of my earlier Flues period catalogues mention chamber lengths.

Beginning with the first NID catalogue in 1926 they state -- "Unless otherwise ordered Ithaca .410 Cal. and 20 Gauge guns are chambered for the standard 2 1/2 inch shell, 16 Gauge for 2 9/16 inch, 12 Gauge for 2 3/4 inch and 10 Gauge for the standard 2 7/8 inch shell." The 28 gauge doesn't appear in NID period catalogues until 1932 though they did make some. Beginning with the 1927 catalogue the sentence is changed to -- "Unless otherwise ordered Ithaca .410 Cal. guns are chambered for the standard 2 1/2 inch shell, 16 Gauge for 2 9/16 inch, 20 and 12 Gauge for 2 3/4 inch and 10 Gauge for the standard 2 7/8 inch shell." Ithaca catalogues for 1926, 1927, 1927-1928, 1928, 1929, 1930, 1931-1932, 1932, No. 50F, and No. 51S, all list 16-gauge as 2 9/16-inch chambers. Beginning with the 1932 catalogue the 28-gauge with 2 7/8 inch chamber is added to the list and it also introduces the 3 1/2 inch Magnum Ten Gauge. By Ithaca catalogue No. 51F the 16-gauge is finally listed with 2 3/4-inch chambers and the 410-bore with 3-inch chambers. I believe the catalogues No. 51 equate to 1934.

My memory has 1933 as the year Ithaca started chambering 3" for the .410. I'm not sure why I recall that.

A 1913 Lefever Arms Co catalog atates that all 12ga guns unless otherwise ordered will be shipped with 2 3/4" chambers. No length is specified for the other gauges.
I have a fairly late (likely around 1910-12) 16ga H grade LAC gun in which the chmbers measure 3". RE-Cut??. But at what point in time would there have been more lilelyhood of someone wanting a 16 with 3" chambers than when it was made. I seem to recall that many of the "Optional" lengths of hulls were taken off the market around WWI time.

Ithaca Gun Co. 3-inch .410-bore Chambering -- July 1933 National Sportsman �

"We have not seen the official announcement but we have heard rumors that a 3" .410 shell was coming and on April 13th Norman Pillot of Houston, Texas, whom you may remember as having won the Amateur Live Bird Championship at Kansas City a short time ago, if my memory serves me right, wrote us that he was sending the barrels of his No. 4 ejector .410 Ithaca to be chambered for the new 3" shells. He also wrote us that last year he killed 180 ducks, 120 doves, 40 jacksnipe and broke 47x50 Skeet targets with this same .410 Ithaca.

In anticipating the stepping up of the .410 load, as we have previously anticipated the stepping up of loads for other gauges, all our .410's from the least expensive to the most expensive in either Ithaca, Lefever, or Westerns, have been built with material and strength enough to be rechambered for the 3" .410 and then handle it with a great big factor of safety.

I think it would be well to caution all users of .410s against using a 3" shell in the shorter chamber and I think that caution would bear repeating from time to time as applied to all makes of guns, because they still keep doing it with disastrous results.

You may say that any of our three outfits will furnish any of their .410s chambered for the 3" shell without additional charge for the longer chambering, and you may also say that the Ithaca Gun Company will rechamber an Ithaca or a gun of any other make for the 3" shell at a cost of $2.50 per barrel; and all the Ithaca Gun Company would need would be the barrels."

The Western Cartridge Co. January 1, 1933, booklet Western Ammunition for Rifle, Revolver and Shotgun only lists 2 1/2 inch Super-X .410-bore shells. The next issue I have is dated March 15, 1934 and it includes the 3-inch .410-bore Super-X shell with 3/4 ounce of shot. The 2 1/2 inch shell still has 3/8 ounce at that time, and it remains 3/8 ounce in the March 15, 1935, Western Ammunition for Rifle, Revolver and Shotgun. The December 24, 1936, Western Price List is the first thing I have showing the 2 1/2 inch .410-bore with the 1/2 ounce of shot we take for granted today.