Marlin 1894C Design Pressure

[Groundhog]

I have read of different max pressures for the .357 round and the Marlin 1894C (.357) in different reloading books and from experts. The variety of comments and opinions have left me with two key questions:

(1) Is the Marlin 1894C designed for more (Paco et al) than the ind. std. of 35 kpsi? The owner's manual is silent on this critical point.

(2) Why do reload manuals listing max loads in CUP generally show a higher max powder load than those in psi (i.e. Hodgdon 158gr H110 is 16.7 gr vs. 15.5 gr. from Speers?

References:
Speers Manual #14: Normal industry pressure for 357 rifles: 35,000 psi
Paco (a): Marlin...rifles will easily take 40 to 42,000 psi
Alliant Power (pistol loads 357): 33,600 psi
Hodgdon Manual 2008 (pistol loads 357): 43,200 CUP
Lyman Casting 3rd Ed (pistol loads 357): 42,000 CUP

(a) See http://www.leverguns.com/articles/paco/ ... rature.htm

[AJMD429]

Likewise, I wonder those things. I realize the lawyer-factor prevents any gun maker from just saying "xx,xxx psi" or whatever, but it seems that everyone generally recognizes some guns as 'stronger' than others, merely due to obvious design factors.

Often the focus seems to be action strength, and I understand that is important, especially with tapered cases, but for straight wall cases, it seems like the cartridge diameter would be important as well, since the barrel thickness depends on the cartridge diameter - I'll bet a gun/action that would be 'stressed' with a hot .45-70 load could tolerate one heck of a lot more pressure in a case the size of a .30 carbine or .357.

I sort of judge it by how high a pressure 'other' chamberings are offered in for that action (from the factory), and what diameter case is being dealt with. I'd rather hot-rod a .357 to 60,000 psi than a .454 to 55,000, all else being equal.

But then we don't always know that actions or barrel steel are 'equal' other than the assumption that for manufacturing/inventory purposes there might be an advantage to them being similar for the various configurations offered.

[blackhawk44]

There are two totally unrelated measures of pressure used in the industry. Those companies using the older mechanical system of copper crusher deformation lists their results as CUP. A more modern computer based measurement of barrel metal strain reports its values as PSI. It depends on which system the individual testing company is using as to whether they list CUP or PSI. Again, while both systems have their own functional value, they are unrelated, have no correlation and cannot be converted from one to the other.