PDA

View Full Version : what is the Max chamber pressure for the 112 Heavy Barrel



Bill
02-02-2013, 05:11 PM
Model 112 HB
sn F104849

Does anyone know what the maximum safe chamber pressure is for this rifle?

scope eye
02-02-2013, 05:17 PM
What chambering is it?

Dean

Cycler
02-02-2013, 09:41 PM
Maximum chamber pressure isn't often defined by the rifle but by the brass case. This is particulary true for bolt actions where action stiffness and strength isn't the limiting factor the way it is for lever actions.

MrMajestic
02-02-2013, 10:13 PM
The brass is the limiting factor in most bolt actions. Typically it is in the case head which expands and the primer will travel to those unknown voids never to be seen again! Don't ask me how I know. Again, what chambering?

scope eye
02-03-2013, 05:31 AM
Just in case you are not familiar with the term chambering, caliber is the size of the bullet, when asked what chambering, you are asking what particular model within that caliber,IE: 300 savage - 308 - 30-06 -300 winmag - 300 weatherby, the 300 savage has a max of around 50.000 psi and the weatherby has almost 70.000 psi max, and they other rounds fall somewhere in between, so that's why we are asking what chambering, the SAMMI specs will determine the max psi, hope this helps,

Tanks Dean

bigedp51
02-03-2013, 10:10 AM
As stated many time above your brass is the limiting factor and the quality and hardness of brass varies.

Below, a case being fired under normal chamber pressures with the red and yellow areas showing the high stress areas.

http://i122.photobucket.com/albums/o254/bigedp51/deform.gif

Below, an exaggerated image of excessive chamber pressure and the brass starting to flow at the unsupported base area, see dotted lines of original shape.

http://i122.photobucket.com/albums/o254/bigedp51/flow.gif

Below, on the outside right and left are military Lake City 5.56 cases and in the middle is a Federal commercial case. Please note the military brass is thicker at the primer flash hole and these cases are harder in the base than .223 cases. These cases strangely are very close in case weight with the military cases averaging less than a grain more in weight.

http://i122.photobucket.com/albums/o254/bigedp51/fedcasethickness.jpg

http://i122.photobucket.com/albums/o254/bigedp51/556hard-a.jpg

http://i122.photobucket.com/albums/o254/bigedp51/hardness-a.jpg

http://i122.photobucket.com/albums/o254/bigedp51/brass-hard.jpg

scope eye
02-03-2013, 10:24 AM
Tanks Big cool animation

Dean