Excessive Pressure Indicators

Here is a way to dtermine if your handloads are creating excessive pressure. There are other indicators other than these but I'm demonstrating the most common signs related to the handloader. Other signs include but not limited to "smoked" primers. This is where gases escape between the primer and the primer pocket. Punctured primers can be a pressure indicator but also can be a firung pin that isn't guaged correctly. Split case walls and a frosen bolt or slide. Be carefull and read the signs.

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[miravox]

@gilream: good thought -- but why would my modest-velocity hand loads exhibit the muzzle blast when my full-speed factory ammo didn't? I used R-22 powder below manufacturer recommended max, got about 150 fps LESS than factory ammo.

[ammosmith]

@miravox It's the hot gases igniting in the air. It's very comon with certain types of powder. Even low end loads can seem to boom as much as a maximum load.

[madisonelectronic]

You can detect hi pressure when you realize the rifle bolt is sticking out of the back of your head.

[ammosmith]

@madisonelectronic That rarely happens. Revolvers do go kaboom in a big way though.

[miravox]

Ammosmith: My .270 Win handloads show none of the overpressure signs mentioned here. HOWEVER, they repeatedly blew the white, plastic diffusers off of my chrono at a distance of about four feet (immediately after I fired several rounds of factory ammo through it with only a little shake & shimmy). Whaddya think?

[ammosmith]

@miravox Unburnt powder and muzzle blast perhaps.

[ariel4more]

is the crater around where the firing pin strikes still a sign of overpressure even if the primer still keeps most of it's composure? I've noticed this on my .45's. Also, all my rifles are savages. I think i've figured out how they brag about, "the definition of accuracy". they seem to have less freebore than other rifles, judging by the sugested c.o.a.l's in my manuals, the bullets would be jammed into the lands. Is there a general rule of thumb for the max pressure with different headspacings?

[MrHellyeah2010]

thank you sir, very handy info there!

[gilream]

ammosmith..you may want to mention one more thing that you may have left out. For me the most obvious pressure sign is a shiny mark on the case head. This results when excessive pressure causes the brass to flow into the ejector recess in the bolt face. When you get to this point STOP. Most likely culprit is that you've exceeded the safe limit with your powder.

[gilream]

@miravox ...perhaps your chronograph is too close. 4 feet does no sound like it's far enough away.

[W857TYWH408576NW0348]

sweetass motherfucken video nigga. cheers.