The Firing Line Forums - View Single Post - Stainless Tikka .243 exploded at the range today

MeekAndMild · December 16, 2004, 06:27 PM

You've got to understand that rifle barrels can get stress risers anywhere the radius of curvature of a corner is very small, i.e. every edge of every groove. So microscopic cracks can develop as a matter of routine, even though most of the time they never go anywhere unless the barrel is overstressed, like in shooting overloads, or with throat erosion from magnum loads.

But if the alloy is hard or brittle then bigger cracks can occur more easily and propagate quicker. With a sailboat you're only seeing forces of maybe 5,000 or 10,000 pounds but the fittings get more angular flexion. With rifles the flexion is smaller but the pressures are much greater. The sailboat rigging failures I've seen occurred under high winds but how do you create a low pressure situation in a rifle barrel.

Only stainless barrels I'm really comfortable with are my Glocks, which have no lands nor grooves (thus less potential for stress risers), .22s because they are thick and low pressure and my black powder rifle, because of the need for rust resistance and the fact that I can load it to only 100 grains of powder. Turned down on a really good buy on a Steyr last week because it was stainless.

More discussion on fatigue resistance and crack propagation:

http://www.key-to-steel.com/Articles/Art45.htm

http://www.thefiringline.com/forums/...p/t-66380.html

December 16, 2004, 06:27 PM	#25
MeekAndMild Senior Member Join Date: August 2, 2001 Posts: 4,988	You've got to understand that rifle barrels can get stress risers anywhere the radius of curvature of a corner is very small, i.e. every edge of every groove. So microscopic cracks can develop as a matter of routine, even though most of the time they never go anywhere unless the barrel is overstressed, like in shooting overloads, or with throat erosion from magnum loads. But if the alloy is hard or brittle then bigger cracks can occur more easily and propagate quicker. With a sailboat you're only seeing forces of maybe 5,000 or 10,000 pounds but the fittings get more angular flexion. With rifles the flexion is smaller but the pressures are much greater. The sailboat rigging failures I've seen occurred under high winds but how do you create a low pressure situation in a rifle barrel. Only stainless barrels I'm really comfortable with are my Glocks, which have no lands nor grooves (thus less potential for stress risers), .22s because they are thick and low pressure and my black powder rifle, because of the need for rust resistance and the fact that I can load it to only 100 grains of powder. Turned down on a really good buy on a Steyr last week because it was stainless. More discussion on fatigue resistance and crack propagation: http://www.key-to-steel.com/Articles/Art45.htm http://www.thefiringline.com/forums/...p/t-66380.html __________________ In a few years when the dust finally clears and people start counting their change there is a pretty good chance that President Obama may become known as The Great Absquatulator. You heard it first here on TFL.