Hi John,
I respectfully submit that your bolt  thrust pressures are based on entirely different pressure levels. My info gives the 32/20 at 17,700 cup and the current 38/55 is the HV level of 33,200 cup. 44's were never made to the HV spec. The 32/20 case head area is right at .66 of the 38/55 or to put it the other way the 38/55 has head with 1.515  more area than 32/20. Given those numbers, the bolt thrust would be 2324 pounds bolt thrust with both cartridges at your pressure level for the 32/20.

That said, I do agree with your maximum case head size for longevity of the action.

I bought my 32/40 in '85, my very first single shot. It has the hammer block that bares on the squared off firing pin it's self and it's a 7 o'clock extractor ser.# 10,551. I knew nothing of singles shots at that time accept that I loved them. So, I went out and bought a box of John Wayne ammo and sighted it in  I've fired no more than 200 rounds of the loads I listed above in this thread and it's still as tight as it was when i bought it, John Wayne loads and all. I have to say that it was in as new condition when i bought, all blueing and color caseing in tack and the barrel like new inside and out.

Very respectfully,

Frank

Well, I need to thank all of you for your encouragement to not fire this rifle.  I was actually thinking of shooting it.   I may decide to sell it after all since it has been re-blued, and I can't shoot it either.  That's two strikes against it.  If I do decide to sell, I will give consideration to those here who have expressesd some interest in it.  Thanks again.

frnkeore, I'm trying to figure out where you came up with your numbers. SAAMI specs for the 32-20 is 16,000 psi and the 38-55 is 30,000.
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The area in front of the rim is the part used for figuring bolt thrust, sort of like hydraulic cylinders. You can't rely on the brass gripping the chamber walls to hold some of the pressure. While this will hold sometimes there is always a chance of case head separation.
To figure area the formula is Pi  R squared. Area for the 32-20 is .0983 X 16,000 = 1,574 pounds . Area for the 38-55 is .1395 X 30,000 = 4,184 pounds. 
The 25-35 that broke the breach block has a bolt thrust of 5,871
I know, my numbers are different from the first post. I used a different book for sizes.
Please except my apology if I'm way off base here.
By the way, that's a nice looking rifle.

Quote:


The preceeding may be found in the 4th paragraph  at

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The SAAMI pressure specs for the 38-55 from the link John kindly posted are 30,000 cup. The same pressure spec is listed for the 32-40.

The way I read it, the SAAMI compliant loads would be something akin to a +P or +P+ loading when used in the Stevens 44, so I'm not surprised that the old 44 actions loosened up or worse when fed a steady diet of SAAMI spec rounds. And didn't SAAMI show up some time after the 44 was designed? 

It's important to know the original pressure level your firearm was designed for, and to load accordingly. 

Frank, that is a really nice 44! 

Frank,

I recognise your formula for area from engineering. The version I learned was   area = [ (dia squared)/4 ] x Pi
Your version just leaves dia squared as is and divides Pi by 4 to give the .7854 constant. We end up in the same place.  

Forgot to add in my previous post that your experience using a tight 44 in excellent condition with the John Wayne SAAMI level loads demonstrated that the action had at least some ability to handle pressures above its intended design criteria. The key of course is not to intrude into the design safety factor.

Regards,
BP

I worked in Hydraulics for years and figure the chamber wall like a cylinder and the brass like a piston. If there is a case separation in front of the rim then the whole area of the chamber diameter would be used, also if there is any lube on the brass that keeps it from clinging to the chamber wall, it would create the same effect. I know I probably figure worst case scenario but it only take one time to wreck your day or your life. Working with guns  daily I get to see a lot of failures and it scares me a bit.
Then there are people who just don't understand like the man that wanted me to put a 50 BMG on and old break open 10 gauge.
I hope I didn't offend anyone here but I would rather be on the safe side than the sorry side.

Joel Black wrote on Oct 23^rd, 2010 at 2:46pm:


I have had several 32-40s and 38-55s come through the shop, never saw one that I would want to shoot. They were all wore out and the hammer no longer held the breach up the way it was intended. Maybe the ones I see are sent to me because of the problems.  All of them looked really hammered. I don't know what types of loads were used in them over the years but many looked like they had been seeing to much pressure. I appears if one was properly treated it would hold up as yours has done.