Black Powder vs Smokeless velocity for .32 and .38 S&W

T

TruthTellers

New member
Since the topic involves black powder and BP cartridges are pretty much a reloaders only thing these days, that's why I'm putting the topic here. Also, y'all here in the reloading section are smart fellas who always give me good responses.

So, I saw a .38 S&W H&R topbreak for under $150 and it looked decent enough, but it was a black powder model. I've generally strayed away from such things because I don't care to deal with the cleanup, but when I realize I'll probably only shoot it twice a year, I figure if one looks good in the future and has a short 2 inch barrel, I'll grab a .38 H&R or Iver top break.

It's got me to thinking tho, how much more velocity in the .32 and .38 S&W does smokeless get if any more velocity at all? Could we use 4Fg, Triple 7, or Old Eynsford black powder/subs to increase the velocity of the .32 S&W and .38 S&W?
 
At least one of the old BP loads in 45 Colt got a 250-grain bullet to 900 fps without exceeding standard pressure. So BP is not necessarily a slouch, but it does want some case volume to work that well because it's energy content per grain is lower.

If you search on the two rounds, you will find BP loads mentioned. A caution is that I've seen some of the same charge weights suggested for both rounds, so I am guessing some of the old information has been crossed up and I would look for multiple sources to confirm them.
 
Unclenick said:
At least one of the old BP loads in 45 Colt got a 250-grain bullet to 900 fps without exceeding standard pressure. So BP is not necessarily a slouch, but it does want some case volume to work that well because it's energy content per grain is lower.

If you search on the two rounds, you will find BP loads mentioned. A caution is that I've seen some of the same charge weights suggested for both rounds, so I am guessing some of the old information has been crossed up and I would look for multiple sources to confirm them.
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With .45 Colt I've seen the 900 fps with a full load of black powder and for standard pressure that usually ends up around 950 with a few different powders. I can't imagine that blackpowder .32 or .38 S&W is going to be much less than that compared with smokeless and another factor is that even if these were smokeless, I'd have to download the loads anyway for use in top breaks. It seems with black powder that is not an issue.
 
I don't know about increasing the velocity. If you're loading holy black (3Fg in pistols please) you get what you get. After I broke my H&R, I quit loading smokeless. Measuring 1.7 gr. of HP-38 was a pain anyway. I went to Alliant Black MZ, now discontinued. So far, so good. Have not run it over the chrono, and I really don't care. I do know from other applications that BMZ runs about 15% faster than holy black. Although it is no longer available, there are other substitutes with a similar formulation.

Remember, the weak point on these topbreaks is the latch.
 
ligonierbill said:
I don't know about increasing the velocity. If you're loading holy black (3Fg in pistols please) you get what you get. After I broke my H&R, I quit loading smokeless. Measuring 1.7 gr. of HP-38 was a pain anyway. I went to Alliant Black MZ, now discontinued. So far, so good. Have not run it over the chrono, and I really don't care. I do know from other applications that BMZ runs about 15% faster than holy black. Although it is no longer available, there are other substitutes with a similar formulation.

Remember, the weak point on these topbreaks is the latch.
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I'm aware of that, I have run some warm .32 S&W Long in a top break just to get a feel for the difference and to see if it could take it. I do wonder tho if the reputed fragility of the top breaks has more to do with people shooting smokeless loads in black powder models, which would of course shorten the service life.

We're starting to drift into more about top breaks and less about black vs smokeless in the calibers most top breaks are chambered for.

About the measuring of the powder charge for these calibers, when I got the Young American .32 I had to measure out 1gr worth of Bullseye and it got old quick. When I found out it could shoot .32 Long wadcutters, I switched to that, much easier to load than the .32 short.

I'm starting to think that it may be better to just load black powder for all these top breaks. When I'm done I can take the grips and the barrel off and just throw the whole frame into an ultrasonic cleaner to clean the residue off.

If I could get within 50 fps with more energetic black powders/subs compared to smokeless, I can't see that as a bad way to go. Plus, it's just more fun to shoot black.
 
It's got me to thinking tho, how much more velocity in the .32 and .38 S&W does smokeless get if any more velocity at all?
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Smokeless powders can generate much higher velocities than black powder. They can do this by generating MUCH HIGHER PRESSURES. When smokeless loads are held to black powder pressures, they generate black powder velocities.

Could we use 4Fg, Triple 7, or Old Eynsford black powder/subs to increase the velocity of the .32 S&W and .38 S&W?
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Possibly, but I doubt you'll see anything significant. For one thing, the gun(s) you're talking about have very short barrels. 2" is quite short and black powder has a tendency to not reach its full potential in short barrels.

You could be looking at a situation where a bunch of your powder charge is blown out the barrel, then ignites.

In simplest terms, to get higher speed from a bullet, you need to push it harder (higher pressure) or you need to push it longer. (more barrel length).

I'd be quite leery about raising the pressure in a top break pistol, and a 2" barrel doesn't "push" the bullet very long...

Even if you get 50fps increase, its a very small change and not likely to matter in any real world sense.
 
44 AMP said:
Smokeless powders can generate much higher velocities than black powder. They can do this by generating MUCH HIGHER PRESSURES. When smokeless loads are held to black powder pressures, they generate black powder velocities.
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Which these low pressure cartridges don't have.

It seems like whether you go with black or smokeless there won't be much difference.
 
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