Drew from the information you have provided it would seem that if there is sufficient wall thickness there should be no reason to be concerned about shooting < 9000 psi loads in a gun equipped with decarbonized steel barrels.

It was interesting to see the old Remington ads with the guaranteed for nitro powders at the time.

How long were decarbonzied barrels offered by Remington or any other manufacturer, seems Parker dropped them early.

Given the choice between an attractive Damascus or Twist pattern vs. the plain black of the decarbonized steel barrels the reason that Parker Bros. dropped offering decarbonized barrels would seem obvious.

Decarbonized steel finishes to a lower sheen or polish resulting in a somewhat satin look. It is a very deep black and easily colored. I have done both Remingtons and Parkers.

Brad

I've read that Remington didn't approve of Parker using the term " decarbonized steel " barrels seeing how Remington first used it.

It is assumed the “Remington Steel” used on the K Grade (Model 1900) Hammerless and (1894) Hammerless Grade “F.E.” Trap Gun (introduced in 1906) is similar to Marlin “Special Rolled Steel” and Winchester “(Cold) Rolled (Bessemer) Steel” with a tensile strength of about 66,000 psi..

Remington introduced Ordnance Steel for the (Model 1894) Hammerless Double in 1897. The 1902 catalog stated the Remington Ordnance Steel tensile strength was 110,000 lbs per sq. inch with an elastic limit of 60,000 psi

The 1889 with Decarbonized Steel was offered until 1908.

Interestingly, Crescent "Armory Steel" (and likely also Aubrey/Meriden doubles) was Decarbonized. This ad from 1926 still lists Decarbonized Steel barrels

http://pic20.picturetrail.com:80/VOL.../387344778.jpg

Due to the wonders of the internet :) we don't have to guess about turn-of-the-century Bulk and Dense Smokeless powder pressures. PLEASE NOTE that modern piezoelectric transducer measurements would be about 10% higher

“1895 Smokeless Powders For Shotguns”
http://books.google.com/books?id=Wv0...J&pg=PA446&lpg
3 1/4 Dram/40 grains DuPont Bulk Smokeless 1 1/8 oz. = 7440 psi
3 1/4 Dram/44 grains “E.C.” Bulk Smokeless 1 1/8 oz. = 7584 psi

The 1933 edition of ”Smokeless Shotgun Powders” by Wallace Coxe and E.I. du Pont de Nemours & Co. reported the pressure for 3 Dram Eq. with 1 1/4 oz. of DuPont bulk smokeless at 9,600 psi.

The 1963 George Herter “Reloaders Handbook” lists 23 grains (3 1/4 Dr. Eq.) of “Infallible” Dense Smokeless, now Unique, with 1 1/8 oz. shot in a paper case with paper wads (card & fiber) at 8,725 psi. (Courtesy of Mark Ouellette)

Of course, only you can determine the pressures that should be used in YOUR Decarbonized Steel barrels.

From Sporting Guns and Gunpowders: Comprising a Selection from Reports of Experiments, and Other Articles Published in the "Field" Newspaper, Relative to Firearms and Explosives, Volumes 1-2, 1897

http://pic20.picturetrail.com:80/VOL.../411162589.jpg

'S.S.' was "Shotgun Smokeless" by the Smokeless Powder Co. (U.K.) which was eventually discarded as loads with more than 3 Dr. Eq. powder had substantially more pressure than those with "E.C." or "Schultze"

Interesting that Parker Bros. used 'Decarbonized Steel' long before any of the dates in Drew's references.... and "Remington didn't approve of Parker using the term "decarbonized steel" when PB first offered it only for their lowest grades beginning in 1869 and ending in 1873.... (according to The Parker Story)

dean i hope i get this right..so they quit useing the decarbonized steel in 1873...then they changed the name of carbon steel to plain steel which is only made in 1875 guns..do i have this corect....charlie

Gunmakers, then and now, made what would sell within a target profit margin. By 1870, Decarbonized Steel was the "new and improved" barrel material for shotguns. But Pattern Welded tubes were being produced cheaply and in great numbers in Belgium, and became the barrel material of choice for higher grade (more expensive) guns.
Sir Joseph Whitworth's adaptation of Bessemer's principle of hydraulic pressure casting was patented in 1874. The first Purdey Pair Nos. 10614 & 10615 were delivered January 1, 1880 with the "New Whitworth Fluid Pressed Steel", and Lefever Arms Co. was the first U.S. maker to supply Whitworth steel for their Optimus in 1887. More "new and improved" steels proliferated rapidly thereafter.

From 1897 Consular Report: Commerce, Manufactures, Etc, Volume 54
United States Bureau of Foreign Commerce
http://books.google.com/books?id=SF1...J&pg=PA526&lpg
Prices for a pair of rough forged tubes show decarbonized was much cheaper than pattern welded:
Steel................... $0.58 (3 francs)
Twist................... $1.16 (6 francs)
Oxford 3 Stripe.... $2.90 (15 francs)
Boston 2 Stripe.... $1.93 (10 francs)
4 Stripe Crolle’...... $4.825 (25 francs)
Unfortunately, I haven't found the cost for Belgian fluid steel made by Laurent Lochet-Habran or Cockerill Manufacture Liegoise

When Crescent introduced the Model 6 sidelock hammerless double in 1904 with "Armory Steel", decarbonized had obviously become the choice for utility grade guns.

decarbonized brls
 

Dean, I believe decarbonized, was used in Parkers as early as 1869, here are photos of my earliest gun ser# 029 a back action gun chambered for the 12-b shell I might have to do two post because of the large size, Gary