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Barreling question, Chamber pressure etc.


Jan 15, 2013
Ok folks got some questions, hoping for some answers

I have a browning 86 receiver I'm going to put a barrel on. I was hoping to chamber for 500 s&w magnum but I think the 60,000 psi is too much pressure given the shank/thread depth and case O.D. for the round, but I think the 500 jrh ( 500 s&w short) at 38,000 will work.

I believe I have the max. pressure of 118,828 psi worked out with a hoop calculator given the following:

*4140 rifle barrel at 120,000 max psi
*Case od at .526
*500 jrh max chamber press. 40,000
*Barrel thread id at shank .845
*Shank wall thickness at .160

What do you guys think.....am I way out in right field here, would 500 s&w work here given the above parameters. Am I missing anything?

Also I can't find a listing for a 500 jrh reamer......could I just use a 500 s&e magnum reamer, since cases are the same except for being a bit shorter.
I believe I have the max. pressure of 118,828 psi worked out ...

I question the stress value of 118Kpsi. Check your math. What cartridges is the Browning 86 action (the Miroku lever gun?) barreled for from the factory? That should be your best guide.

Seems like factory ammo is loaded to 50Kpsi although Hodgdon gives data with pressures in the mid 50's area.
The strength of the barrel is irrelevant if the action can't handle the pressure and bolt thrust. Calculating hoop strength would be secondary to staying within the strength of the action.
hi, first time poster.

How did this turn out? i read the bit where you said 120,000psi and leapt into my quickload program, 60,000 psi max
Well it has been a very stressful time in addition I am very old.....so I've been slowly moving along and saving my money. I am almost finished with my maching on my rifle....should be done today. I have decided to go with 50 JRH as a caliber. I have to find and purchase a reamer (PTG) hopefully.....then give a final sanding......color case harden and blue then the wood.

It is a takedown winchester 1886....the barrel extension is all done and timing to the receiver and barrel are within .015" so this morning should almost do it except for the tapered octagoning and then a round tapered portion of the barrel.....I will wait to headspace when I get the chamber reamer.
...sorry for rambling on and on.
PTG make good reamers, they just take there sweet ass time, i'm in the UK, give mansons a call see what they have on the shelf maybe?
As for rambling on, jeez no, its good to see someone else just doing this with their hands and taking the time to pass on the info, looking good so far.
Caliber wise, is that the .500 Jeffery Rimless your'e chambering in when you say .50 JRH? thats a whopping caliber if it is, keep the updates coming.
The 50 jrh is a 500 s&w magnum short. Same as the magnum but a shorter case. I started the octagoning the barrel today....hope to finish or almost finish tomorrow.

My grandfather used to sell newspapers on street corners in London. He and his brother 1000001206.jpg1000001207.jpgblacked shoes on a ship for passage to America. My oldest son got back last year from serving as liason with 3rd royal marine commando brigade.
It's almost beer time and I'm whuuuped. I hope I get the barrel done tomorrow and then on to taper rounding the forward part of the barrel and then I'l start thinking on that reamer. Sorry for my grammar I'm tired and old.
Got the octagoning done. Now I do all the rough sanding, draw filing til it gets pretty good then I'll round taper the 1st 4-5 inches 1000001208.jpg1000001209.jpg1000001211.jpg
Well......my wife and I live in a very remote mountainous part of Montana. We see an awful lot of grizzlies, lions, moose and even wolves. I carry a firearm with me 24/7. When you least expect it you can run into one of varmits and sometimes even the 2 legged type. You just never know in these times.

I think I'm going to put a semi bucktail on the rear and a linear fiber optic on the front. I've never had to use a firearm up here yet, but you never know. I came eyeball to eyeball with a lion bout 3 months ago and it was in no hurry to leave.
OK the barrel is done except for final sanding and fitting. I will now move on final fitting and sanding of all parts, then color case hardening, bluing and wood.


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that looks really good! i particularly like the round going to octagonal barrel, might give that a go on one of mine, I tend to paint all of mine with cerakote to avoid the dreaded brown as long as possible, i'm so jealous of where you live, over here in the UK you can't spit and not hit someone.
Yah, we certainly are secluded. I have to go out and hit the local watering hole once a month or so....else I 'd go crazy. I take one of my dogs, have a few beers, share a bar basket and go home


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trust me, being away from humanity isn't a bad thing, get that rifle built, i'm really looking forward to seeing how it turns out.