Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Rifles, Bullets, Barrels and Ballistics


Reply

17-4 PH Stainless cut rifled barrels

 
LinkBack Thread Tools Display Modes
  #1  
Old 12-25-2010, 08:25 PM
Junior Member
 
Join Date: Sep 2006
Posts: 4
17-4 PH Stainless cut rifled barrels

I am about to have a batch of cut rifled barrels made out of 17-4 Ph stainless steel and was curious as to whether or not you guys shooting over-bore large capacity magnums might be interested in a barrel that would last say 2,500 accurate rounds versus's the 800 or so that one often gets. The 17PH is hardened to about 44RC in comparison to 416R which is about 28RC which is why the barrel life is extended by approx 3 times.
So what do you think, if they prove to be just as accurate as 416 tubes but life is greatly extended would they be of any interest to you overbore boys? ( BTW have no concerns about chambering the harder steel, its not a problem.)
Reply With Quote
  #2  
Old 12-25-2010, 10:05 PM
Gold Member
 
Join Date: Mar 2006
Posts: 848
Re: 17-4 PH Stainless cut rifled barrels

That is very interesting.
As long as they prove accurate over a longer period ,
it all depends upon the cost of the barrels.
Reply With Quote
  #3  
Old 12-25-2010, 11:44 PM
Junior Member
 
Join Date: Sep 2006
Posts: 4
Re: 17-4 PH Stainless cut rifled barrels

Well thats the idea of using 17-4 Ph, it is significantly more corrosion resistant than 416. In addition to the superior corrosion resistance it is approx 50% stronger than 416 and doesn't have the cold temperature failure issues that 416 has. Krieger for example will not sell a stainless tube in less than a #5 contour for this reason. Lothar Walther barrels use a material that is similar / same and I have had a giood run with those previously but they are button rifles and cannot have gain twist rifling.......... Which brings me to the next point. It makes more sense to have the rifling start almost straight and then progressively sped up to the ultimate twist rate. So for example a 30 cal tube would start out at twist rate of 1-100" and progressively get faster till it ends up in a 1-10" twist. The pressure peak resultant from the bullet being wedged into rifling that is say at 36 degrees (over the first inch) as opposed to being virtually straight in front of the throat should provide significantly less peak pressure and a smoother transition for the bullet.

Anyway, it should be interesting and fun to see how it all pans out. It will be interesting if nothing else.....
Reply With Quote
  #4  
Old 12-26-2010, 01:17 AM
Gold Member
 
Join Date: Sep 2009
Location: McLean, Virginia
Posts: 985
Re: 17-4 PH Stainless cut rifled barrels

Very interesting stuff. A few questions, how expesive is this 17-4 PH steel compared to 416? If it is so clearly better, I'm surprises it hasn't been done before. Seeing as this isn't an extremely new alloy or such, just a different, harder kind of steel. If going this way, what about using AR500 armor plate steel to make barrels??

Welcome to the site! Sound like
someone who will fit right in here, trying to push the limits and experimenting!
__________________
"Out of range" is a theoretical concept as far as I'm concerned. Send it!
Reply With Quote
  #5  
Old 12-26-2010, 01:13 PM
Platinum Member
 
Join Date: Jun 2010
Location: greenwood, IN
Posts: 3,576
Re: 17-4 PH Stainless cut rifled barrels

Quote:
Originally Posted by sirrocco View Post
Well thats the idea of using 17-4 Ph, it is significantly more corrosion resistant than 416. In addition to the superior corrosion resistance it is approx 50% stronger than 416 and doesn't have the cold temperature failure issues that 416 has. Krieger for example will not sell a stainless tube in less than a #5 contour for this reason. Lothar Walther barrels use a material that is similar / same and I have had a giood run with those previously but they are button rifles and cannot have gain twist rifling.......... Which brings me to the next point. It makes more sense to have the rifling start almost straight and then progressively sped up to the ultimate twist rate. So for example a 30 cal tube would start out at twist rate of 1-100" and progressively get faster till it ends up in a 1-10" twist. The pressure peak resultant from the bullet being wedged into rifling that is say at 36 degrees (over the first inch) as opposed to being virtually straight in front of the throat should provide significantly less peak pressure and a smoother transition for the bullet.

Anyway, it should be interesting and fun to see how it all pans out. It will be interesting if nothing else.....
finally somebody got it right about just how junky 416 stainless is! But you did leave out the fact that it's a "high retained martensite steel" as well. This one of the main reasons 416 is not recommeded for use in extreme cold weather. One thing to keep in mind about 17PH4 rearc melt steel is that it will rust! If it will harden (with one known exception), it also will rust. The exception is MAR-10. MAR-10 is stronger than 416, and comes shipped with a 28-32 rc (you may be able to order at a higher hardness). Machines slightly tougher than 416, but I'd say it's similar to 420 in machinability. The stuff is so rust resistant that you can put a block of it in deionized water for six weeks with no sign of rust (416 is usually about 3 or 4 days)

So far most folks shy away from 17PH4 due to it's machining qualities, and tooling is closely guarded. So good luck to you! P.S. the stuff is kinda hard on equipment, and a Jap lathe rarely comes back after a good wreck machining the stuff. Also did do any investigation into the newer 500 series? I never did any work with that one, but the paper work looks very interesting.
gary
Reply With Quote
  #6  
Old 12-26-2010, 01:19 PM
Platinum Member
 
Join Date: Aug 2003
Location: NC, oceanfront
Posts: 3,264
Re: 17-4 PH Stainless cut rifled barrels

Who would/could finish them?
Who rifled and lapped them?

I'm interested
Reply With Quote
  #7  
Old 12-26-2010, 01:23 PM
Junior Member
 
Join Date: Sep 2006
Posts: 4
Re: 17-4 PH Stainless cut rifled barrels

Well all these things have been done before - Barrels made from 17-4Ph (walther) and gain twists, by a number of people but not the 2 together. The reason most barrel makes dont want to use 17-4 is because it can prove to be a rather large pain in the ass to machine.
I havent priced 416 lately but am guessing 17-4 will be twice the price, maybe a little more. In addition to the price difference of the raw material the machining, drilling, reaming, rifling time will no doubt be extended and cutter life reduced. So the end result will have to cost a bit more. This exercise is not about making something cheaper tho', (there's truckloads of people out there doing that) its about making something better in every way possible. The end will be stronger, last significantly longer, more corrosion resistant and hopefully be as accurate, foul the same, with less peak pressure, as standard 416 tubes. Its nothing new really- just combining a bunch of "previously done" into one package.
Not sure of the machinability, temerature stability, or corrosion resistance of armour plate, so dont know whether or not it would make good barrels. There are other methods of hardening the surface of barrels to achieve similar results that we will also be experimenting with. Perhaps barrel makers like the idea of built in obsolescence? So they can sell more.....
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: 17-4 PH Stainless cut rifled barrels
Thread Thread Starter Forum Replies Last Post
WTB: .416 and .458 stainless barrels AL1 Gun Parts - Stocks, Barrels, Actions, etc. 3 10-30-2011 06:33 AM
Rifled slugs shot in a rifled barrel gonewest Long Range Shotgun Slug Hunting 1 08-18-2011 04:11 AM
5r rifled barrels 94Winchester Rifles, Bullets, Barrels and Ballistics 21 07-09-2010 06:07 PM
AR-15 complete upper. Stainless bull, button rifled 20-inch barrel G-gear Guns For Sale 0 07-20-2009 07:52 PM
Polygonal rifled barrels and monometal bullets???? NorthernSniper Rifles, Bullets, Barrels and Ballistics 9 01-18-2004 08:58 AM

Current Poll
Do you archery hunt for elk?
YES - 31.41%
60 Votes
NO - 52.88%
101 Votes
Not yet, but I plan to. - 15.71%
30 Votes
Total Votes: 191
You may not vote on this poll.

All times are GMT -5. The time now is 10:55 PM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC