.44 Magnum and .454 Casull

I don't have these in similarly sized guns so I can't tell you. I think the difference would be small enough to be insignificant next to the recoil of either. (For instance, would you notice an extra couple drops in a full glass of water?) If anyone has a chance to try this comparison IRL, I'd be interested to hear about their experiences.

As was already stated, the .454 achieves the same energy at lower pressure. That's because the weight is spread across a wider bullet and the case is larger. That said, remember that the extra width of the .454 bullet should punch a slightly larger hole...
 
In this case pressure has more of a function over the time it takes to destroy or work loose the revolver. The 45 bore will throw a 240 grain bullet at the prescribed velocity with less wear and tear than the .429 bore. again simple physics.
 
It is recoil and friction that eventually wears out revolvers, not pressure. If a gun fails from pressure then something bulges or ruptures--that's definitely the exception in terms of what finally wears a gun out.

Usually a decent quality revolver that hasn't been abused wears out because of the moving parts wearing against each other (friction), or being banged against each other by the forces of recoil. In either case, pressure isn't a factor.
 
riddleofsteel wrote:
In this case pressure has more of a function over the time it takes to destroy or work loose the revolver. The 45 bore will throw a 240 grain bullet at the prescribed velocity with less wear and tear than the .429 bore. again simple physics.
Click to expand...

I hadn't thought of that. You have an engineering mind, sir. I have another consideration to add. I haven't handled a whole lot of examples but I have noticed important design differences between .44s and .454s. An obvious reason for this is that one cartridge is larger than the other but is one designed to be stronger than the other? (This is definitely the case with .454's super-magnum cousin, the .460.) Even if not, the size difference alone should change the tolerances. Any thoughts on that?


JohnKSa wrote:
It is recoil and friction that eventually wears out revolvers, not pressure. If a gun fails from pressure then something bulges or ruptures--that's definitely the exception in terms of what finally wears a gun out.
Click to expand...

I think there was an assumed correlation between operating pressure, recoil, vibrational stress, etc...
 
I think there was an assumed correlation between operating pressure, recoil, vibrational stress, etc...
Click to expand...
The assumption is incorrect. There is not a correlation between operating pressure and recoil (as already discussed) nor, in general, between operating pressure and vibrational stress.

A simple example would be to compare the relative durability of guns firing 9mm and .40S&W. Both operate at similar pressure and yet there would be little debate that given similar firearms, the 9mm will be more durable. The higher slide velocity (recoil velocity) due to additional ejecta momentum of the .40S&W is what makes the .40S&W harder on guns in spite of the fact that it operates at the same pressure as the 9mm.

Similarly, 9mm and .357Magnum operate at the same pressure and yet no one would suggest that the durability of two basically identical revolvers, one chambered for 9mm and the other for .357Magnum would be the same as a result of the identical operating pressures. Clearly the additional recoil of the .357Mag is going to make it harder on guns than the 9mm even though they operate at identical pressures.

The .45ACP operates at much lower pressure than the 9mm. In spite of that, no one would suggest that in identical guns the 9mm will wear out guns faster than the .45ACP due to the higher operating pressure of the 9mm.

Finally, we'd have to concede that a revolver chambered for .45-70 is going to last much longer than one chambered for 9mm if we try to correlate low pressure with longevity.

It is true that there is additional stress on a gun (primarily the chamber and barrel) that operates at higher pressures. However in terms of longevity, this is a red herring.

If a gun were to fail from the repetitive stress from pressure, the failure would manifest itself as a rupture or bulge of the chamber or barrel. We don't see those kinds of failures showing up as the result of long use. That kind of failure is the result of an overpressure cartridge or a defective firearm--not the result of a high round count.

Guns wear out from moving parts rubbing together (normal wear and tear from friction) and from recoil banging things around and slamming parts into each other until something eventually cracks or deforms.
 
Pressure and heat are closely related as increased pressure causes an increase in heat that will accelerate wear on your barrel. Pressures at the highest levels can cause catastrophic damage such as barrel ruptures. Excess pressures not high enough to cause barrel ruptures will still cause damage over the long term. Excess pressure can result in barrel erosion, broken lugs, eroded breechfaces, and cracked slides among other things.
I guess this is the type of wear I was referring to not parts rubbing together. Anyone that has shot hot .357 ammo in light frame revolvers and had excessive backstrap and forcing cone erosion or frames stretched and the entire gun loosened up knew what I meant.
That is why magnum guns are built heavier than the average revolver, to handle the pressure.

Not to be argumentative just my experience.;)
 
This,
Excess pressure can result in barrel erosion, broken lugs, eroded breechfaces, and cracked slides among other things.
Click to expand...
and this,
Guns wear out from moving parts rubbing together (normal wear and tear from friction) and from recoil banging things around and slamming parts into each other until something eventually cracks or deforms.
Click to expand...

are, I think, looking at the same thing, from different angles.

Like any other machine, guns wear, as they work. Every time you fire, there is some barrel erosion.

Pressure is what make the gun work, and so, in general terms, it is all about pressure, for without that, nothing else happens.

BUT, pressure alone, (as we normally discuss it,) is not the critical factor in service life, until you get well above normal operating levels.

It is the combination of factors, including pressure level that make the difference. Pressure over area, and time, creating recoil and friction, not just the psi level of a load is what wears out things.

Battered locking lugs, cracks, etc are from things slamming together too hard. Yes, its pressure that is the force behind it all, but how that pressure is applied to the gun, and how well the gun handles it that makes the difference.

35K psi load in gun A could be fine, and in gun B create a much shorter service life. Simply because of what the gun is, not because of the pressure level alone. One example of this is .357 Mag in a J frame size gun, vs. the same ammo in an N frame size gun. Shooting the same ammo (same pressure) which one is more likely to need a tune up first?
 
Pressure and heat are closely related as increased pressure causes an increase in heat that will accelerate wear on your barrel.
Click to expand...
I suppose one could make the argument that increased pressure will accelerate bore erosion. That's going to be much more of an issue with rifles than with pistols since bore wear in pistols is pretty much just friction wear caused by the bullet going down the bore. You don't see the throat erosion and heat damage in pistol barrels that is common in rifles.

It appears that throat erosion and internal barrel wear in pistols is related to factors other than pressure.
Pressures at the highest levels can cause catastrophic damage such as barrel ruptures. Excess pressures not high enough to cause barrel ruptures will still cause damage over the long term. Excess pressure can result in barrel erosion, broken lugs, eroded breechfaces, and cracked slides among other things.
Click to expand...
SOME of these things are related to pressure, some are not.

Pressure causes things to rupture or bulge. So barrel ruptures are certainly pressure issues. Cracked locking lugs are also likely pressure related, but guns don't typically fail from ruptured barrels or cracked locking lugs in the absence of overpressure or a serious defect in the part involved.

This is what I was getting at when I said that if manufacturers expected that long use would eventually result in barrel ruptures or broken locking lugs they would have to issue safe round count figures for those guns. If a normal failure mode for heavily used guns was for a barrel to rupture or for the locking lugs to give way, there's no way that manufacturers could tolerate the liability. They'd have to come up with some way for the owner to know when it was no longer safe to use the gun and when it became probable that the gun was going to have a catastrophic failure.

Cracked slides are definitely not pressure related failures unless the barrel has bulged or ruptured. Cracked slides are the result of the slide banging against other parts of the gun as the result of recoil.
BUT, pressure alone, (as we normally discuss it,) is not the critical factor in service life, until you get well above normal operating levels.
Click to expand...
Correct. Until the issue is overpressure, and not simply pressure, there should be no expectation that pressure is going to wear out a gun.

In other words, when comparing two calibers in two similar guns, it is completely inaccurate to automatically assume that the gun firing the higher pressure load is going to wear out faster. It is far more accurate to assess durability in terms of recoil and normal wear & tear friction than by comparing pressure.
 
Last edited:
I suppose one could make the argument that increased pressure will accelerate bore erosion. That's going to be much more of an issue with rifles than with pistols since bore wear in pistols is pretty much just friction wear caused by the bullet going down the bore. You don't see the throat erosion and heat damage in pistol barrels that is common in rifles.
Click to expand...
Throat erosion is quite common in revolvers, Smith M19s are famous for difficulties with high pressure lightweight bullets causing erosion.
 
Well, if that's true then I think I'll have to back off my comment suggesting that higher pressure will accelerate throat erosion. Since 9mm , .40S&W and .357Mag operate at the same pressure and neither the 9mm nor the .40 are known for throat erosion, clearly pressure can't be the reason for the throat erosion in the .357Mag.

I'll adjust my previous post to reflect that.

Thanks.
 
Yes, these issues are all interrelated and polycausal. Good comments on the difference in frame sizes for .357. Getting back to the original question and a consideration I added, any thoughts on the contribution of build differences between .44s and .454s?
 
You must log in or register to reply here.
Back
Top