Pressure signs damaging your rifle

[tapper]

Hi guys,

Getting further into the reloading and have a question about this.

I'm learning about pressure signs and see that some of common ones are extruded primers and the case head extruding into the extractor recess.

If you found that happening you'd obviously stop shooting the loads if you had any sense, but would you have any any damage to your firing pin area or extractor in the process?

[Jack V]

By the time the brass head is extruding any place pressure is way too high. This is not the early preventative signs of pressure that you normally look for.

The early signs are primer starting to flatten at the edges . Primer fully flat . Primer starting to crater in addition to excessive flattening . Hard bolt lift . Hard extraction .

Primer splitting and or gas blow by at the primer. Once the pressure is at a point it expands the solid case head by a measurable amount it is becoming dangerous .

Constant use of high but otherwise safe pressure will wear the bolt lugs quicker and set them back quicker creating more headspace earlier than if lower pressures were used . Any extrusion of brass would mostly likely come after a head separation so that can definitely damage firing pins, extractors , magazine wells and if bad enough blow up the whole action .

Some actions will show primer cratering even when the pressure is normal some Remington's will do it . If the primer edge is still round and the powder load in the safe range then the cratering on such an action can be ignored . As long as no other signs are evident . In this case use harder primers like Remington .

[Chronos]

Not much more to say, I think jack v has nailed it.

Chronos

[Oldbloke]

+ 1 Pressure is way too high. Back off

[Tiiger]

If you found that happening you'd obviously stop shooting the loads if you had any sense, but would you have any any damage to your firing pin area or extractor in the process?

Cratering primers I've seen start to bevel the firing pin hole in some rifles if shot enough.

You'd be stupid to have kept shooting with the cratering loads long enough to do it though.

[tapper]

Jack - Thanks for the all the info.

Chronos - Thanks for confirming

Oldbloke - Not having these problems myself. Just reading up, learning... avoiding problems before they happen

Tiiger - Understood, thanks.

[Mich]

By the time the brass head is extruding any place pressure is way too high. This is not the early preventative signs of pressure that you normally look for.

One thing to add to that.

I've read people putting this down to some brass being softer than others. In the last instance Federal brass was blamed for being too soft.

In this shooters humble opinion, I have to say that's bulls**t.

Agree with Jack, pressure it was to high if the head is extruding, regardless of brass brand.

[headspace]

Some people keep a shell holder handy when they get up around maximum. If the fired case has to be pushed hard into a shell holder it's definite sign of over pressure.
JD

[tapper]

Because it's distorting the head, JD?

[Jack V]

To jam in the average shell holder would mean it has expanded so much it probably swelled the chamber slightly or is close to head separation . To get that bad either the shell holder would need to be quite tight to start or you have ignored all the early pressure signs. I think it's much safer to watch closely and interpret the early signs correctly so you don't go too far as the brass will not last long being over stressed even if it don't fail prematurely .

[Korkt]

IMO, not if you're observant of warning signs and back off when appropriate. Nothing will be worn or damaged in your rifle.

I couldn't tell you why, but there are guys who are obsessed with maximum velocities who'll ignore the early signs in the pursuit of my speed. Ignoring signs is sure to give you problems sooner or later, and potentially with serious ramifications.

[Jack V]

Nothing will be worn or damaged in your rifle.

That's not correct mate . As the pressure rises more force gets applied to action parts especially bolt lugs and if any gas leaks happen bolt face damage will occur to some degree . Major gas leakage can blow and extractor right off . Actions that have bee constantly subjected to high pressure will become looser and show increased headspace with time compared to the same action subjected to lower pressure loads. Staying within the accepted reasonable pressure range will not show any major differences over time but loading max all the time does have negative effects down the line .

[Korkt]

I will expand on what I said above. I typed it in haste and my original reply was missing information I should have included. You're right, Jack.

What I meant to say was... If developing a load and you begin to see pressure signs, then back off, you will not have caused any appreciable accelerated wear and will not have caused any damage to the rifle by reaching the point where pressure signs were visible for a few testing shots.

As for continually shooting loads with heavy charges... I think this will become and debate of splitting hairs should we continue it.

For any hunter, casual target shooter... Anyone except a competitive shooter doing a high volume of shooting, I would say shooting max loads (I'm referring to ADI data here and their max thresholds as this is where my experience is based on) would have no appreciable effect over the life of the rifle and their experience with it.

Chambering will play a part too of course. Are we talking maximum charges in a 223, 308, 300wm, 338, 50 cal.... We could both find examples for and against I'm sure.

That's my 2c anyway.

[tapper]

Thank you both Jack and Korkt.