doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com phili 16ga Fox Sterlingworth

Thanks Bill!! Another question however. In the lawsuit are they saying that the specific steel used by Remington they were referring to, namely AISI 1140, has a higher level of sulfur content then other steels used in barrels by other manufacturers?

Treb,
I'm a machinist not a metallurgist, but I would imagine when the sulfur content is high, and is unevenly distributed (stringers) it would lead to weak spots, especially after pressure cycles.
Sulfur makes for EZ machining. You may have heard of "sulfur base cutting oil".

I can promise you that if the example I saw was in barrel steel, no way no how would it have passed any kind of proof. They actually looked more like cracks.

I would think there is a metallurgist here who could give us a more technical description.

I'm interested in the results pertaining the the Meriden and if they are similar to the Crescents

As you know Joe, Sears catalog No. 117 of 1908 listed the No. 18 double and the single barrel No. 424 A.J. Aubrey guns with �Genuine Armory Steel� AND �Genuine Crystal Barrels�. Catalog No. 124 of 1912 listed the No. 18 double with �Decarbonized Steel�.

The c. 1910 single barrel METL tested for me had (Bessemer) Decarbonized Rephosphorized Carbon Steel (no AISI equivalent but similar to AISI 1211) with a Tensile Strength of 71,500 psi. That is actually better than the industrial standard for AISI 1020 at 61,000 psi ("hot rolled" bar).

For comparison -
Bessemer or Decarbonized Steel: Henry Bessemer initially claimed a tensile strength of 40 tons/89,600 psi but published numbers range from 55,000 to 70,000 psi, with an average of 63,000 psi. The higher number likely represents �cold rolled steel�.
Whitworth's Fluid Compressed Steel: 66,000 - 67,200 psi
Marlin Model 1898 Slide Action Shotgun �Special (Cold) Rolled Steel�: 66,000 psi
Winchester Standard Ordnance (Bessemer) �Rolled� Steel: 69,400 psi
Krupp (Open Hearth): 70,000 - 80,000 psi
Krupp Fluss Stahl (Homogeneous Fluid Steel) introduced about 1890: No published data but by composition it is similar to AISI 1045 with a tensile strength of 85,000 psi
AISI 1140 Resulfurized Carbon Steel: 79,000 - 85,000 psi
AISI 1040 Carbon Steel: 76,000 - 90,000
AISI 4140 Cr/Moly: 95,000-100,000

Please note that Carbon Steels may be heat treated to much higher strength, which I believe the action forgings of 1020 (at least Hunter Arms') were.

My understanding as a machinist, not a metallurgist, is that heat treating doesn't begin to give much increase in hardness & strength until about 30 points of carbon are reached. The 1020 frames would have been carburized & given a hard case with little effect on the core of the frame. This was in fact I believe the intent.

Realize it doesn't take much carbon to have effect. The 40 points of carbon in a 1040 steel amount to 0.4% by weight. Thus for every 100 lbs of iron you would have only .4 lbs of carbon or 4lbs per 1,000 of iron.

1020 was likely chosen for the ease of machining and carburizing/case hardening.

For us non-metallurgists
http://www.azom.com/article.aspx?ArticleID=9145

For the academics amongst us
http://www.academia.edu/7652999/A_Case_Study_of_Heat_Treatment_on_AISI_1020_Steel

Excellent web site, more to my question and the Remington law suit,

http://www.azom.com/article.aspx?ArticleID=6593

Interesting note,

"Carbon is the major alloying element present in carbon steels. They also contain 0.4% of silicon and 1.2% of manganese. The AISI 1140 carbon steel is a free cutting steel. It has high strength, and is combined with sulfur in order to increase its machining characteristics"

Could that be the problem right there?

California Chuck (Chuck H) knows all this stuff, I don't know why he doesn't post up.