Any advantage to lower pressures?

P

Pond James Pond

New member
Previously, given that I load VV and they only post velocity data, I've never actually given pressure much thought beyond signs of its excess in my fired cases.

However, provided they are below the SAAMI max for a given firearm does a lower pressure have any advantage for the shooter?

What do I mean? Well here is the example that got me thinking from the online Hodgdon data table for .44 Mag.

Lil'Gun max load with 29.5gn for a 200gn bullet gives 1794 FPS. It develops 36.2K CUP.

However the same bullet with 10.8gn of Titegroup only pushes the bullet to 1433 FPS but makes 38.4K CUP.

I imagine that Titegroup is a faster burning powder and so that initial pressure is higher but shorter lived than the Lil'Gun data.

Is this all that is being seen?
Are there more consequences, good or bad to take into account beyond velocity?
Or is this an insignificant data point as long as it is below SAAMI maximum for that gun/calibre?
 
I was always suspect of the claimed low pressure created by Lil' Gun in revolvers. Recoil from it compared to other powders supposedly making much higher pressure and similar velocities always seemed similar. I think those reported lower pressures are one reason so many folks jumped on the Lil' Gun Bandwagon. Then came the documented accounts of excessive flame cutting, substantial heat increases and premature forcing cone erosion. Apparently one needs to pay the piper. That price is too high for me, I don't use Lil' Gun anymore.
 
Then came the documented accounts of excessive flame cutting, substantial heat increases and premature forcing cone erosion. Apparently one needs to pay the piper. That price is too high for me, I don't use Lil' Gun anymore.
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Well, from a performance stand-point I was not seriously thinking of Lil'Gun given that N110 gives better velocity with none of those scary associated side effects you mentioned. All those were new to me at the time of reading your post, mind...

As it happens i was looking to see if there were powders that I could use in .44Mag that might produce performance closer to that of a mid-range .44Spl, so light .44Mags. I used the Hodgdon online page and selected all the powders that the only Hodgdon stockist I know of here has listed on their website. Lil'gun just caught my eye due to the disparity in velocity and pressure.

In the low-power magnum respect, Clays, Universal, Titegroup, HP-38 and N320 from VV all look promising. I have the last already for .38Spl in my snub.
 
However, provided they are below the SAAMI max for a given firearm does a lower pressure have any advantage for the shooter?
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Doing the job with less pressure is good. High pressure is bad, low pressure is good. This is very broad brush but less pressure means less stress and strain on the structural elements of the firearm. This will increase the firing cycles till some sort of structural failure. When you are dealing with gunpowder you have a substance which the burn rate has an exponential slope. Humans don't think in exponential terms, but exponential processes get out of control extremely fast. Low pressures give more margin from error or castestrophic failure than high pressures.


As it happens i was looking to see if there were powders that I could use in .44Mag that might produce performance closer to that of a mid-range .44Spl, so light .44Mags. I used the Hodgdon online page and selected all the powders that the only Hodgdon stockist I know of here has listed on their website. Lil'gun just caught my eye due to the disparity in velocity and pressure.
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Try Unique. You can cut the charges in the 44 Magnum and still have good accuracy with a lower recoil. while 1000 fps may not seem very slow, this 44 Mag always pushed bullets a bit fast. I am certain in a different, looser pistol, the average velocity would have been in the 900's.

S&W M629-4 Stainless, 5" Barrel

240 LSWC 8.5 grs Unique thrown, Midway Brass WLP
25-Nov-04 T = 58 °F

Ave Vel = 1023
Std Dev = 25
ES = 99
Low = 958
High = 1057
N = 30
 
They don't sell Unique, so that is out. The powders listed in the preceding post are those listed for .44Mag that I can get fro Hodgdon.

I'd be loading for 200gn plated and I was looking at loads that might be around 1100fps. I use the same bullets in .44Spl and they make about 900fps. In the RH they are very soft shooting.
 
Personally, I am not a fan of Titegroup specifically. ( Especially in small cases like 9mm. )

Many people use it though.

Is your bullet jacketed ?

A small error in charge weight results in a large increase in pressure.
And the difference between Min. charge weight and Max. Charge weight is always much smaller then other powders.... so make sure your powder drops are on the money. Even the Min. charge weight produces high pressures for most .44 Mag loads.

Unique or Bullseye is more forgiving in .44 mag.

Remember charges that don't fill the case sometimes can produce uneven velocities... stemming from the powders position in the case when firing.

If it is all sitting by the primer it usually ignites best.... if it is all sitting towards the bullet it can be unevenly burnt. I read an article decades ago on that subject... so I would be hard pressed to find it again.

I think a good crimp helped any powder position "issues".... but don't quote me...

I would Google it... and make your own choices...

https://www.google.com/search?q=Powder+position+in+a+.44+mag


I ended up using Unique.
 
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As it happens i was looking to see if there were powders that I could use in .44Mag that might produce performance closer to that of a mid-range .44Spl, so light .44Mags.
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I saw a thread over on one of the reloading forums where people are having lots of success using BE-86 for this purpose. From all accounts, it is great stuff - meters well, burns very clean, scales up or down nicely (within its intended range), has flame retardants so less fireball and no flame cutting, etc. The only downside is that it is still hard to find.
 
There are several powders I could recommend, but I understand that you cannot get them where you live, and I don't have experience with they powders that you can get, so I'm sorry, no help there.

In GENERAL, lower pressure is a good thing, IF you get the velocities you need. Pressure only really matters as a means to obtain velocity, although there are certain gun designs where pressure, within a certain range is critical to proper function of the arm.

It is heat & pressure (primarily) that erodes barrel steel. Lower pressure also means less strain on all parts, including the shooter. Logic says that should mean longer service life. I do not know if that is actually true in any practical sense.

You would have to conduct exhaustive, extensive, and expensive testing to determine if there was any practical difference. Does a gun running at 35k wear out and fail before one running at 30K? Or 25K? Is it 100 rnds sooner? 500? 1500? 15,000? I don't know. And I don't know of anyone who does know, with certainty.
 
Are there more consequences, good or bad to take into account beyond velocity?
Or is this an insignificant data point as long as it is below SAAMI maximum for that gun/calibre?
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Max loads are based on pressure rather than velocity. The simplitsic answer to your question is that if a loads's pressure is significantly below max, it can be stepped up until it reaches max, which is why you can easily have higher velocity from lower pressure loads with slower powders. A powder that is slower to peak, and takes longer to decline in pressure produces a higher velocity than a fast powder that peaks to max pressure quickly, and drops off quickly.
 
Pond,


Of the powders you have listed, I have used one of them in my 44 Mag w/ 240 gr. plated. W231 / HP-38.

I have run it to jacketed data max w/o pressure issues or signs.. the only issue was accuracy dropped off. HP38 down loads well so it is a good candidate.


Universal is supposed to be Hodgdons analogue for Unique so it is another contender. I just can't speak for it as I haven't actually used it.
 
I would think for most of us here (and we are dedicated hobbyists), we'll not likely find the wear limits of a .44 Magnum revolver even though we certainly do more shooting than most gun owners.

Now someone that did a number of years doing IMHSA competition could probably be in a better spot to comment on the kind of wear that our different loads/powder would put on a handgun.
 
Interesting responses. Indeed, initially I was posting about pressure as a general point with my .44Mag musings as a context, but responses specific to that were very helpful.

HP-38 and Universal look promising simply because I can get them. Always a good start!

I notice that max pressures for those are well below the listed max for .44Mag, so I imagine in those examples it is result of case capacity being insufficient.

I suppose the issue of lower pressure meaning lower punishment was kind of self-evident if I'd thought it through... :o
 
Mr. Pond, I will encourage you to be careful when reading published loads and attempting to draw conclusions from what you read. Do know that using FASTER burning powders in large capacity/high pressure applications (.44 Mag) means early peak pressure.

You will see the reported pressure shown with the max published load...
This is because a quality published data source will show everything that is relevant.

My point?
A "max" load with Titegroup or HP-38 may show lower pressure at published max but the reason for that is the testers -KNOW- that it is not (at all!) the best choice for the application and they cut the charge because they know that a fast powder gets very squirly VERY quickly. They publish their max charge to keep you away from a load that goes stupid.

Bottom line from my viewpoint:
I would rather go beyond published max (carefully) with the correct powder for the job... than even build to published max in a super-fast burning target powder like Titegroup.
 
You won't be able to get HP-38 much longer.
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Well, according to a number of posters on that thread, the rumour is just that, so perhaps it is not an endangered species after all. Fingers crossed.

I would rather go beyond published max (carefully) with the correct powder for the job... than even build to published max in a super-fast burning target powder like Titegroup.
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My personal interest in those powders was for low power paper punching loads so I'd be looking at mid-range loads from those powders anyway as my goal is .44 Spl-esque experience. In other words, I shouldn't be wandering into dangerous territory.

For fire-breathers I already have N110 which is doing a grand job!!
 
I want the best in accuracy and I prefer to get it with least pressure (stress).

When working up loads I will select several powders to get the most accurate grouping. I also like to fill the case as much as possible as a part of accuracy.
I prefer lower chamber pressure also.

I load a Ruger 77/22Hornet (K Hornet) and Lil'Gun is the only powder I use for accuracy. It gives me every thing I want with plenty of Velocity. The most notable characteristic of Lil"Gun is low pressure. In 40>years I have never found any powder so perfect and where I use it.

The 44 Mag with your bullet has it's requirements and you haven't found Lil'Gun doesn't like it. But then again that's what you have found.

Don't blame the powder.
 
Lol, bold faced and italicized.

The "most notable" characteristic of Lil' Gun appears to be damage to revolvers.
YMMV. But it was Freedom Arms that came to THAT conclusion.
 
I have to say, from my perspective, best accuracy or not if the powder is chaffing away at my revolver's health to an excessive degree, then it's not getting in my gun....
 
I have to say, from my perspective, best accuracy or not if the powder is chaffing away at my revolver's health to an excessive degree, then it's not getting in my gun....
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The word "excessive" is the prime word there. All slow burning powders used for legitimate magnum loads will chaff away at the revolvers longevity. That is why for most range sessions many of us do not use "max" or "near-max" loads even if they are the most accurate. Better to use something a tad less accurate for busting bowling pins or cans and save the gun from abuse. This has been my argument against Lil' Gun. While many rave about the velocities it achieves at a lower claimed pressure and scoff at claims by major gun manufacturers and others about it's excessive flame cutting, I see no reason to take even the slightest chance of risk by using it in my revolvers. Too many other options out there that perform terminally just as well.
 
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