SB2 frame with Partner barrel...what steel???

[NFG]

I was checking the local shops for NEF barrels, rifles and other "stuff" and found a relatively cheap 20 ga shotgun, I wanted another setup for a couple of other stub barrel projects running around in my mind.  While I was looking at the shotgun I remembered reading ".223 Partner" on the barrel stub I'm using for my present projects.

I couldn't take the shotgun apart to see which frame it had and from what I've read it should be an SB1.

Now...I'm wondering what steel is in the 223 Partner barrel...1137 or 4140?

The SN on the 20 ga is NJ 33XXXX so I understand that would be a 1995 make.
The SN on the .223 Partner is NS making it a 2002 make.

Tim or Larry...can you shed some light on this matter.

I want to do a 20 cal VarTag, 20 Tactical or 204 Rem next using a threaded collar ala TrotterLg to lock the barrel on the stub along with locktite or J&B weld or similar agent, turned as large a diameter as possible...boring the 20 ga out to 0.925 would leave barrel walls somewhere around 0.273" thick.  The stub walls would be about 0.093" thick and would serve more to hold the stub barrel than for strength...I'm still working out the strength aspect of the 1137 steel, but I don't see any problem.

Thanks for any input

'Njoy

[quickdtoo]

Current production shotgun barrels are 1137, dunno what they were made of then.

Tim

[NFG]

I think I confused the issue.

I wanted to know if the .223 cal Partner barrel is 4140 or 1137?  I thought/understood all CF barrels were 4140, but the "Partener" reference has me wondering.

I am trying to work out a formula that will give a close approximation of of the pressures over the areas in question using the normal pressure ranges of the different steels so I can be relatively comfortable with the projects I'm doing.  I will post the data if I ever get it solved.

'Njoy

[quickdtoo]

Current production centerfire rifle barrels are 4140, what they were in 2002 I don't know, you might call Gordon and ask, I've only discussed older frames with him, not barrels. Even Gordon may not know, he said they had no records to show what changes were made to frames when, the same may be true of barrels. Other than resorting to a metallurgical test, you may never know for sure.

Tim

[NFG]

Thanks, Tim...It may not matter what steel is in the barrel for how I'm using it...even 1137 has twice the strength needed as a "receiver" anyway and as things are going with NEF, Remington, etc...I won't be purchasing any more of those products anyway.  These projects are basically learning, experimental and most likely "throw away".

The brass came in, the 6mm BR, .242 neck reamer should be here tomorrow or Friday, the barrel is set up...it is snowing.......I still have to hook up the "through the barrel" coolant/lub system and I should have the chamber done by Saturday...if all goes well.

As soon as I can find some 17 BR brass I will get that barrel chambered, also.

'Njoy