Here are some loads I just been shooting with the 30-338 Lapua Imp during some testing with a really powder fouled barrel... in the 700 action. Peak PSI has the last two zeros dropped, so 75,000 PSI reads 750 under the "Peak" column.
Cases were all sticky coming out, bolt lift and extraction were also stiff. Primers had craters about .010 - .020" tall too! Don't use these loads!
250 rounds ago, most of these loads were plenty mild to shoot, but after not cleaning for over 75 rounds, pressure and MV had risen to unacceptable levels.
After cleaning, pressure dropped about 6,000 psi on these loads, but not all the way to where it had been. So, it's my best guess, that some roughening of the bore has occurred and forcing me to drop back on the powder charges I first started out with that had been in the low to mid 60,000 psi range.
After a good break in period, I've seen a few barrels require the loads to be reduced just like this one, and possibly for the same reason?? Something to be aware of...
At any rate, I'd still like to see for myself what PSI it takes to get one of these actions to fail.
The bolt is contained parallel within the bolt bore. Therefore, for that reason alone, only ONE lug tearing loose, that just makes no sense to me at all.
I do not know much about P17's or any of the Mauser's, but I know they were not all created equal in strength, and that is just common knowledge. I like to know every detail in a situation like DC described about, and there are many of them that are sadly left out. For this reason, not a whole lot can be learned from this "expensive" account.
I will post pictures and all the details of the destructive testing I do, and I'll use another action to verify the first ones failure level and location... This could get expensive... However, it seems no one is really interested in laying this out for the public, and it's something that should have been tested time and time again in REALITY, then published.
A good place to start seems to be these 240gr SMK I have and 4831 then. It may take a 338 cal bullet to blow it up though, any bets?
Can you run the numbers and tell me what pressure should cause the lugs to yield, and what pressure they should shear.
The receiver diameter is about 1.35" in diameter. With that, you could figure the point the barrel the receiver ring should yield, and where it should fail. If you need the case diameter to figure the pressure vessel's wall thickness, it's .585" in diameter.
[ 02-22-2004: Message edited by: Brent ]