Shotgun Choke Tube Question

[metalhd9034]

Hey Folks,

A customer of mine brought me a muzzle brake(basically a door breaching brake) for a Remington 1100/870. It attaches via an extended Improved Cylinder choke tube, with threads on the end. So, layout is this: choke tube screws into barrel, threads stick out of barrel, muzzle brake screws onto choke tube. Somehow the last couple of threads snapped off inside the barrel, and the choke tube is basically ruined. I'm pretty sure I can replicate the choke tube and make my own (I've had zero luck in finding a replacement, either the company that made it is defunct, or this may have been a custom job) but what I'm not sure on is what specific type of material most companies use to make choke tubes out of? I'm assuming some sort of stainless steel, but probably not a 300 series that isn't magnetic. Does anybody have any experiences making a choke tube? If so, what did you make yours out of? Is there any specific material that is a definite "No No" when making a choke tube? Any thoughts, ideas, suggestions are greatly appreciated. Thanks!
~Metalhd9034

 

[oneounceload]

IIRC, Briley uses 416 s.s. for theirs. You might call the gun company and ask what they have theirs made from (doubtful they make their own, most don't)

 

[metalhd9034]

416 was my best guess too, but since I've never machined one before I thought I should get an outside opinion.

 

[natman]

I can't imagine that anyone can possibly machine a choke tube for less than you can buy one ($33).

http://www.midwayusa.com/viewproduct/?productnumber=837639

 

[metalhd9034]

"I can't imagine that anyone can possibly machine a choke tube for less than you can buy one ($33)."

I agree, but this is a customer and if they are willing to pay...I won't argue. Secondly, since that brake is a proprietary design, and only works with that specific choke tube he would be stuck with a brake that is now a glorified paperweight. It's a pity to just let something sit and not be used if you can fix it and use it again for a reasonable cost.

 

[chas08]

can't imagine that anyone can possibly machine a choke tube for less than you can buy one ($33).

But if you are a machinist, you do it because you can. And as one, I'd go with 416 also. It will rust easier than 300 series but it is some tough stuff. It ought to be fun grinding a threading tool for those fine threads...heh...heh

 

[metalhd9034]

Yeah I was thinking about that too. threads....grr I also debated about re-creating the brake itself with the choke tube all in one piece and that way I would have one less set of threads to worry bout.

 

[chas08]

Well if your thread pitch and major diameter for the breacher attachmment were the same as the choke tube threads it would simplify things. You could cut them all at once at the same lead setting. It might require a little "fancy handywork" with the crossfeed and the halfnut. You could do a mock up out of brass to figure out what works. Or you could spend $33 like natman suggested.(LOL)

 

[n/apower]

I think 416 is a very poor choice for a shotgun choke. Most chokes are 17-4. This includes Briley's offerings (other than their Ti tubes, of course).

 

[Milkmaster]

What is the chance you could buy an extended choke and then machine the extended portion for the muzzle brake to fit? Half the job would already be done!

 

[Virginian]

17-4 or 400 Series will both machine a lot easier than the 300 Series in my experience, and I would think either would work fine. This isn't a huge metallurgical challenge. 300 Maraging steel would be best... but also most expensive.