Chamber size of Sterlingworth 12 Gauge

[kdross]

I have an AH Fox Sterlingworth 12 gauge from 1928. The gun is a Philadelphia gun. What size chambers should this gun have - 2 1/2 or 2 2 3/4?

Thanks.
Ken

[gunut]

Most likely right between the two....2 5/8...A H Fox said that all 12 ga guns were chambered for 2 3/4in but they tended to hold the chambers about 1/8in short....Later Savage guns were actualy marked on the barrel as being 2 3/4in and most actualy were.....

[kdross]

Thanks gunut.

So what size shell should I be using?

Ken

[Researcher]

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 ¾ 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 recently published 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. A recent issue of The Double Gun Journal carried an article on tests showing no significant increase in pressure from shooting shells in slightly short chambers. IMHO I don't much sweat that 1/8-inch in 12-gauge guns. On the other hand when one gets a 20-gauge chambered at 2 3/8-inch likely intended for 2 1/2-inch shells I do worry about folks firing 2 3/4-inch shells in such guns.

I've been shooting 2 3/4 inch 12-gauge shells in my Ansley H. Fox doubles for over 40 years. For high volume shooting like Skeet or sporting clays I use low pressure 7/8 ounce hand loads, but except for very light weight guns with 4-weight barrels, I don't hesitate to use 1 1/8 or 1 1/4 ounce SAAMI loads when needed.

[kdross]

Researcher:

Thank you very much for the informative post.

Ken