maximum pressure rifle

vitaminado

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Hello
I've always been curious to know what maximum pressure a rifle can hold before exploding.
I imagine that it can vary depending on the rifle, but let's take as an example a factory rifle like a remington 700, bergara b14, browning x-bolt, etc.

I see that many people surpass the loads of the manuals.
I've been loading for a couple of years and I'm afraid to do it

for example the caliber 338 win mag, according to CIP are 62336 psi

When you begin to see the signs of pressure in the brass, have you already exceeded the maximum pressure?

Thanks for your help
 
I would agree with calhunter with a qualifier. There is a vast difference in quality of brass! One brand may show extractor marks far sooner than others. It would certainly mean too much pressure for that particular brass and on some high quality brass, you could have too much pressure even before you see an extractor mark on the case head.
In other words, there could be too much pressure for the brass which may or may not be too much pressure for the rifle.
 
Brass makes a difference for sure, forgot to mention that.
When I started reloading I had some imperial brass for my 308, it always had extractor marks and occasional sticky cases while the rem and fed brass were fine. I finally threw that crappy imperial brass out.
 
Hello
I've always been curious to know what maximum pressure a rifle can hold before exploding.
I imagine that it can vary depending on the rifle, but let's take as an example a factory rifle like a remington 700, bergara b14, browning x-bolt, etc.

I see that many people surpass the loads of the manuals.
I've been loading for a couple of years and I'm afraid to do it

for example the caliber 338 win mag, according to CIP are 62336 psi

When you begin to see the signs of pressure in the brass, have you already exceeded the maximum pressure?

Thanks for your help
The reason you can SOMETIMES excel listed max with a factory gun is because listed loads are worked up in pressure barrels with minimum dimensions. Factory guns can have loser tolerances and CAN sometimes have lower pressure with a given charge. Whenever you get shiny spots you have already exceeded pressure on the combination of components you are using and have to back off the load at least a grain for the conditions you are shooting. More if you want to shoot in a higher temperature than when working up to load. Hope this makes sense. You should mb ever shoot any load that shows pressure signs, use a bigger gun if you are not where you want to be. A chronograph also indicates pressure. If you are exceeding listed velocity with the same barrel length as the manual, most likely you are also exceeding the listed pressure. There are exceptions, but if it is faster than it is supposed to be, be very careful. You are at the edge.
 
At least 120k before an action will "fail". I believe Remington tested the 700 to around 150k. I've seen actions tested to over 200k before "blowing up"...
 
At least 120k before an action will "fail". I believe Remington tested the 700 to around 150k. I've seen actions tested to over 200k before "blowing up"...

barrels are supposed to be tested to a minimum of 1.5x the max working pressure

I know a guy that has pressure trace testing equip and he did some "proof loads" when designing a chamber and barrel profile--he said that the brass would basically "vaporize" before any damage was done to the barrel/chamber or bolt

he said the brass was first to go, then the bolt lugs, then the chamber lugs, then the barrel --he said the barrel damage you see on the internet comes from blocked muzzle or obstruction in the barrel creating an "air void" that can/will split the barrel at any weak point, but in the case of an over pressure round from reloading he said the brass is always the first thing to fail
 
Brass flow is the limiting factor. Much above 62k PSI you'll be seeing one-hitter quitter kind of case life. The rifle is not anything near a limiting factor but will be subject to damage from the case opening up. I've personally fired loads that would be up in the 100K psi territory. BTW, don't do that. It's bad for everything and everyone involved.
 
Thanks for your help.
The truth is that I have never reached a maximum load of a manual, but I am calmer with what you have said.
Currently loadind for 22-250,300 win mag and 338 win mag.
I have not reached the highest speeds, but I get good precision with factory rifles.
 
If you have Ken Waters "PET LOADS" go to page 386 and read about what they experienced with one of the rifles used...they were above industry standards..with apparently no pressure signs in said rifle..combination of barrel wear, chamber and military throating....

Kind of something to keep in the back of ones mind....
 
Cartridges are designed to SAMMI pressures for a good reason, many have been discussed already. The rifle manufactures design there actions around this pressure and add a safety factor of 100%. So if the highest rated pressure for a cartridge is 65,000 psi, most manufactures will design to 130,000 minimum but I don,t advise that you exceed the design pressure because you will be cutting into the safety margin.

If something goes wrong, you need that margin. you also cant rely on any more safety margin or what someone said or has done because of many unknown factors. I have seen many failures that produced enough pressure to blow up many fine rifles and shotguns, also pistols.
and when you run the load data it should not have exceeded double the listed load data, but it did.

The problem is that failures with firearms are normally catastrophic.
so no good can come from it. beyond the design specification, there is only problems with components and equipment.

I stopped over loading years ago when I started gunsmithing and saw first hand the damage and injuries cause by these Philosophies

Stay within SAMMI pressures so that If something does happen, you have a chance of coming out with all of your body parts.

Just my recommendation.

J E CUSTOM
 
Just to add, most chrome moly steel used today for barrels and actions is rated to 200,000psi regardless of manufacturer. Stainless in the order of 416R is maxed at around 160,000psi as far as my research indicates.
Brass is the weak link and is designed to yield below what the rifle does. The head of a brass case will expand and fill the bolt face at just shy of 100,000psi in most BOLT ACTIONS. It is far less than this in other lock types.
It's the gas escaping and expanding that destroys rifles, in most cases the front ring breaks and the barrel falls on the ground.

Cheers.
 
Here is what happens when pressure exceeds design. or design safety margin was not enough.



Just a reminder

J E CUSTOM
 
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