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Thanks for that 400.

With ref to the .458 WM comment please see the winking smilie. and refer to the post I was replying to.

I was in no way indicating that there is a direct comparison to be made between CUP and PSI, that is why I indicated the different units. Not withstanding this if one takes the MAP the 450#2 uses 73% (approx) to acchieve the same performance as the 458 Lott does with 81% of its MAP.
In my considered opinion the MAP for the 450#2 is on the low side as it was standardised (or re-standardised) quite correctly with due regard to the firarms in which it may be fired, many of which are quite old now. We were however discussing a Ruger N0.1 which my experience of, suggests is quite capable of handling far more pressure, as is, again in my opinion, the case design under discussion.
I am not advocating "hot rodding" cartridges, but a lot of people like to do so. I was rather abstractly discussing the possibilities that exist with such a massive bottlenecked heavy case.
Such discussion take place about the 45-70 every day of the week.

Quote
"A-Square's data makes for entertaining reading after a few stiff single malts, but is an insider joke in the industry, as few have been able to come anywhere close to duplicating it. As an example, a manufacturer (who will remain nameless) brought out ammunition for some of the British Flanged Nitro Expresses (I have notes on one in particular, which I won't specify). During their testing, they tried some of A-Square's data, which showed 2150 fps in a shorter than standard barrel at way under CIP max average, in their new state-of-the-art CIP spec pressure gun. They got the same 2150 fps velocity alright, but at 10,000 PSI higher pressure than was claimed, roughly 30% higher and 11% over CIP MAP. BTW, they settled on a final load for their factory ammo that tested somewhat under CIP max, and submitted the ammo to CIP for testing. Their results checked out, and the ammo was CIP approved."
End Quote

Well that is all very interesting. It seem that there is always somebody that has the inside track on things, but of course it is all too hush hush to publish or reveal the sources. That is a shame for us mere peons, but does I'm sure make the "insiders" sleep better in their beds at least.

Pressure testing as you know, has many variables, from primer lot, powder lot, case lot (make), case neck stiffness, ambient temp, crimp, throat length, rifling twist and exact barrel dimension, barrel surface finish, wear ect, that exact duplication of test results is difficult on a week to week basis let alone in different rigs in different places at differnt times. So much so that major ammunition manufacturers alter their loading after testing from one bulk powder to another.

But I am glad that you have raised the issue and I will write to A Square tonight as it appears that I will be in danger by relying on their loading data. I am sure that they will be disapointed that their data (which seems to be one of the very few that do publish such) has been a total waste of time, money and effort and left them open to litigation for their slipshod methods.

Quote "I'll believe that when somebody that actually has a pressure gun tests it." End quote

Well A Square did, they invented it and standardised it. But please refer to my comments below.

This is not designed as an attack on you. I read a number of posts recently where you were praised to the heavens. I am quite prepared to believe that you are as well connected as you state and have access to data that the rest of us do not. If so Sir, then please share your credentials and put that information out with its sources for all to peruse and verify.
If you know for sure, that A squares information may be wrong by as much as 30% then it would appear to be morally incombant upon you to supply people with the sources of this empirical data so that such a dangerous publication can be challenged and withdrawn from print before one of us gets hurt.
To just rubbish the work by inuendo and rumour of others without evidence, just smacks of sour grapes and proberbly borders on the libellous.
It would seem that if forums are not for the free exchange of data and information then they just descend into a pissing contest.

Regards

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