Home Forums Hunting & Shooting Ask The Gunwriters Excessive Pressure

Lots of discussion on pressure signs, velocity and such. Say you run 10,000 psi more than SAMMI says for a particular cartridge, have no traditional pressure signs, an extra 100-150 ft/sec out of it, and great accuracy.
What is the down side of this? Any one care to comment.

Repeated, conatnt firings at 70,000+ tends to eventually "compromise the integrity" of action steel.

Metal fatigue and the possability of a catastropic faliure at some point in time

What are the actual applied stresses that the action components are experiencing?

Those two answers sum it up succinctly.

The interval between trigger and tragedy is far too short to change your mind.

For example some cartridges ( in the '06 class) have a higher ratings than others. Would I get into trouble , down the road, by loading to the highest pressure for that class. Example being a 270 runs higher max pressure than a 30-06 or the 3 levels of pressure for the 45-70 depending on fire arm.
And, do I have to run a 200gr .308 bullet faster in a 1-11 twist barrel to get it to stabilize compared to the 1-10 twist.
I have been working with a Sako M-85 and would like to use 200gr AB's, not really working out unless I drive them hard. Every season I revert back to the Barnes TSX-BT 168gr load in the '06.
I can get reasonable accuracy with 54gr RL-17 @ 2700fps200gr AB

The limiting factor is the rifle. There are no rifles factory chambered for the 270 older than 1935, which is one reason why it has a higher maximum pressure ceiling.

In a rifle of current manufacture, you probably could get away with running a 30-06 to the same pressures as a 270. Maybe. For a while. But for how long? Nobody can say because it hasn't been tested. Your decision, your rifle, your body parts.

Respectively, I don't see a difference in rifles except for the size of the bore.
Although one local person blew up a Marlin lever gun, caused extensive damage to his hand, cause of this was probably that he tumbled/ vibrated loaded rounds with his spent brass.

In a rifle action is the stress induced by increased pressure exponential or does it go in a straight line?

Umm that would be 1925 rather than 1935.

Secondly, a Savage 110 or a Rem 700 (or any modern action originally chambered for the 270) would digest 30-06 loaded to 270 levels forever.
Bolt thrust and radial expansion would be virtually identical since the inside surface area of the cases is the same.

Furprick,

The SAAMI pressure for the .30-06 is only 5000 psi less than for the .270--not 10,000 less, as in your original question.

The maximum long-term healthy level for modern action steels is generally considered to be around 65,000 psi.

Determining what pressure you're getting however is the real issue to overcome.

Sorry, I nine-ringed that 2 into a 3.

I'd quibble about saying you could run 270 pressures in a 30-06 forever. That makes sense in a hypothetical way, but since it has never been done forever, we truly can't say. After every shot, one could say it has withstood the stress so far, but that's all. As I said, it's a quibble.

It's IS true that without pressure gear, you don't know if you're at 270 pressures or 10,000 psi beyond them.

Remember, it is not really hundreds of average rounds that we are most concerned with. With the same loads, pressures will vary quite a bit. What we really need to worry about are the couple of rounds w-a-y o-u-t there on the high pressure end of the bell curve. Since I shoot thousands of rounds over time I AM worried about that one-in-a-thousand round that spikes extra high for unknown reasons. Every thing is hunky-dory until the one time it isn't. Every single round that we fire has the same statistical chance of being one in ten thousand.

I always get a kick out of the guy who didn't have flood insurance, and his house washed away, and he is pissed because he lived in the "once in a hundred years" flood zone.

Ask the engineers who designed the nuclear reactors in Japan if once in several hundred years was good enough.

There is a fine line between calculated risk and unnecessary chances. There is much that we don't know. Why tempt fate with stuff that we do know? Murphy's Law always lays in wait, as does the Darwin award.

is there a safe way to get a 200AB to 2700fps in an '06 with a 22 7/16 th barrel?

I'm thinking it will be difficult to get 2700 with a 200AB in a <24" barrel.

62gr of Magpro gets you close as does 52 of H205 and 56 0f MRP.

I'd experiment with Magpro if I were you. I love that powder for velocity, accuracy, and metering.

The Hodgdon Annual Manual shows just under 2600 fps with that bullet, and a whisper under 2700 with the 190 HDY BTSP. If it were me, I'd call those plenty good enough.

nifty250 & others:

That's a very interesting thot I hadn't THUNK. That 1/1000 or 5000 SPIKE. That deserves serious COGITATION.

Hey Fish, where U been. I haven't seen you post lately.

nasqam, I have been of the same opinion as you. A modern 06 rifle SHOULD handle the same pressures as a modern 270. Still think so BUT might ought to mull it over.

This line of thot was the underlying element of a thread where I asked about a new loading manual with CURRENT pressure tests. I think I will get more serious about 2 NEW MANUALS.

Very Good Thread.....I am listening.

JWALL
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VEGETARIAN.........Indian Word For Poor Hunter

Yep. When you're really only splitting hairs, what you can do with one that you can't do with another, the question always comes to mind "what does that say about the user?" (Not that it isn't fun to do the rifle loony gyration.)