Help with terminology and why I ask

Mikeinkaty

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What is the space inside a cartridge called that is unused by powder?
My question is what percent of the total space available can be left empty. Specifically for a 357 mag cartridge.

The Hodgdon web site says max load for a 125 gr bullet using Titegroup powder is 5.4 grains. That means the powder cavity would only be 1/3rd full. Would that be a problem?

With Trail Boss powder there is no problem. Even at 3.5 grain the cavity is still more than half full.

Thanks, Mike
 
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Smokeless never or very rarely fills the case,it's best to stay between the min and max charge specified by the manufacturer.Black powder or the substitutes are the powders where you don't want any airspace.
 
Do they specify the min? I thought they specified "Starting" which I think is 10% below max. They say to start with that and gradually work up to max. What if you want to gradually work down to min??
 
Always start with the minimum load listed - most manuals will list that & the max - I think alliance's site shows the max & then start 10% below - starting with minimum is always the safe thing to do.

you will probably hear a thousand opinions on titegroup but that is not a powder I would use in a .357 mag & definitely one where you need to start at min & work up - a slower powder would be much better
 
Do they specify the min? I thought they specified "Starting" which I think is 10% below max. They say to start with that and gradually work up to max. What if you want to gradually work down to min??

I think you're using "minimum" and "starting" interchangeably. Your starting load should always be whatever is listed as starting. Therefore, you couldn't work down to it.

Empty space has never been an issue for me. I've heard/read of people using cotton or some other fill on the theory that it keeps the powder in a column against the primer. But it was always in the context of extreme accuracy and consistency.
 
While there are many published compressed load most powders won't require a full case or compressed load, The only case that is not apply is Black Powder. It is very important that BP fills the case and is at least slightly compress.
 
You could call it "air space"

But don't forget the seating depth of the bullet in the case ...it takes up air space
 
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Many of the higher pressure handgun cartridges are initially loaded from the factory with a powder that will fill or almost fill the case under the bullet loaded for that round ,this is especially true for the .357 mag.Then along comes the reloader who has at his disposal faster powders for milder loads,hence the case not filled.
In order to load down to the min you must start at a load that may be max or more for your handgun so you start at the min(sometimes going lower is dangerous) and work up for the particular gun you are talking about,this is VERY important when working with revolvers!
 
I like higher density loads. I simply stay away from the fast burning powders that many prefer.

I like higher density yielding medium burn powders for uniform ignition and safety. On average a double charge of powders like Hodgdon Universal will near fill the case and be quite obvious under visual inspection.

The same applies to rifle loading. The closer to full, the more I like it.

I know many don't agree with my preferences, to each his own.
 
I'm have no Titegroup; just comparing it to trail boss. Putting the max amount possible behind a 158 gr bullet, without compressing the powder, would be around 13 gr which would probably blow up your pistol!! A double charge would easily fit behind the bullet. Plus the volume change between start and max is quite small requiring a precise powder measure.

If 50% empty space is not a problem, then I suppose one could use it to get velocities higher than possible with TB but don't think I would want to use the charger that came with my Lee kit.
 
I'm have no Titegroup; just comparing it to trail boss. Putting the max amount possible behind a 158 gr bullet, without compressing the powder, would be around 13 gr which would probably blow up your pistol!! A double charge would easily fit behind the bullet. Plus the volume change between start and max is quite small requiring a precise powder measure.

If 50% empty space is not a problem, then I suppose one could use it to get velocities higher than possible with TB but don't think I would want to use the charger that came with my Lee kit.



A good powder scale is a very useful tool.sometimes a good one can be found relatively cheap on eBay
 
.38, .357, .44 Special, .44 magnum......

Just for information, these cartridges started life as black powder cartridges that became smokeless powder cartridges. Many smokeless powders take up much less space than black powder. Trail Boss is made bulky with the intention not to be able to overcharge a case and you don't even have to weigh it. Fill it to the bottom of the bullet, back off about 10% and you have your starting load.

These cartridge are also very forgiving of bullet seating depth. The newer smaller cartridges such as the 9mm, 10mm .40 are NOT forgiving of bullet seating depth. If you put the bullet in too deep pressures will rise quickly the deeper it is.

Cartridges that were designed with smokeless in mind have much less free space. 9mm, .40 and such sometimes the powder has to be compressed to get a full charge into a case.

Minimum loads of fast powders like Titegroup and Bullseye barely cover the bottom of the case. Many people are leery of those powders because a double charge can blow your gun to pieces. If you use these you need to develop a very inflexible routine to prevent double charging and check the cases with a flashlight BEFORE you seat the bullets.

No offense, but it seems that you need to study the why's and wherefores of reloading. Many reloading manuals have great ***w to' sections that will answer a lot of question. I'm glad you asked here, though. You are in a good place to get help. Good luck.

PS I got by with only Lee measures for years, but really felt more like a reloader in charge of my own destiny with a scale.
 
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I use Titegoup in .357...

Always start with the minimum load listed - most manuals will list that & the max - I think alliance's site shows the max & then start 10% below - starting with minimum is always the safe thing to do.

you will probably hear a thousand opinions on titegroup but that is not a powder I would use in a .357 mag & definitely one where you need to start at min & work up - a slower powder would be much better

......but in target loads about as powerful as a .38 special.:):):)

PS Using .357 brass keeps from building the crud ring in the chamber of your .357 that .38 cases do.
 
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The Hodgdon web site says max load for a 125 gr bullet using Titegroup powder is 5.4 grains. That means the powder cavity would only be 1/3rd full. Would that be a problem?
5.4gr is not a problem. 10.8gr is a bomb. If you cannot measure powder accurately, low density efficient powders are not for you.

A slow powder that will fill the case before it goes overpressure is safest for an inept or careless loader, but may not be as good ballistically and certainly not as efficient (have to use more powder). I have mentored a few loading students who should stick to factory loads.
 
For example, the .45 ACP produces about the same ballistics as the .45 Colt. But the .45 ACP was designed around smokeless powder and has much less case capacity than the .45 Colt, which was developed way back in the BP days. It takes a lot of BP to duplicate a similar smokeless load. Some may be aware that the .38 Special was originally designed as a black powder round (that is why it has a relatively large case capacity), and in fact black powder .38 Special loads were still available until the late 1930s. God knows why, I guess a lot of people liked smoke and dirty .38 Special revolvers. In terms of energy, weight for weight, smokeless powder releases 3x to 4x more energy than black powder. So much less smokeless powder is needed to produce the same ballistics.
 
Would you please......

I'm have no Titegroup; just comparing it to trail boss. Putting the max amount possible behind a 158 gr bullet, without compressing the powder, would be around 13 gr which would probably blow up your pistol!! A double charge would easily fit behind the bullet. Plus the volume change between start and max is quite small requiring a precise powder measure.

If 50% empty space is not a problem, then I suppose one could use it to get velocities higher than possible with TB but don't think I would want to use the charger that came with my Lee kit.

Would you please clarify this a little? After your first sentence are you talking about Titegroup or Trail Boss. It's almost impossible to overcharge a case with Trail Boss but any more than the few grains that it takes to make a maximum load with Titegroup will blow up a pistol.

Also. What caliber is being loaded with the Lee kit? There should be a chart with the kit that tells how much of each powder a particular scoop throws. They are conservative, so if you follow the chart with the proper powder/bullet combo, it should be safe. For example, my .38 Special Lee Handloader kit came with a scoop that was supposed to throw 2.8 grains of Bullseye for a 148 gr wadcutter. I checked it with a scale and it throws 2.7 grains of Bullseye (with my leveling technique) which is fine with me. That is well under the max load for .38

I also have a whole set of Lee scoops that comes with a big slide chart thingy. I still check each scoop with each powder against a scale so that I know exactly what I'm getting.

UPDATE: I think I see your point. Yes, A double charge of Titegroup would only fill the bottom of the case but will blow a gun to smithereens. It is EASY to double charge with a fast powder.
 
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Would you please clarify this a little? After your first sentence are you talking about Titegroup or Trail Boss. It's almost impossible to overcharge a case with Trail Boss but any more than the few grains that it takes to make a maximum load with Titegroup will blow up a pistol.

Also. What caliber is being loaded with the Lee kit? There should be a chart with the kit that tells how much of each powder a particular scoop throws. They are conservative, so if you follow the chart with the proper powder/bullet combo, it should be safe. For example, my .38 Special Lee Handloader kit came with a scoop that was supposed to throw 2.8 grains of Bullseye for a 148 gr wadcutter. I checked it with a scale and it throws 2.7 grains of Bullseye (with my leveling technique) which is fine with me. That is well under the max load for .38

I also have a whole set of Lee scoops that comes with a big slide chart thingy. I still check each scoop with each powder against a scale so that I know exactly what I'm getting.

Be aware that for any propellant, the bulk density may vary slightly among powder lots, or even over time. Therefore, if you are using dippers, it's essential to weigh charges for those dipper sizes you plan to use to see what the true powder weight is. Same for powder measures. From what I have read on this forum many do not understand the concept of bulk density as it applies to propellants, yet it is an important factor to be aware of. Bulk density simply means the mass of a granular material per unit of volume. There are tables available showing the nominal bulk density for most every propellant on the market, and you might be surprised at the differences in bulk densities among different powders.
 
Something like 8-16% is what the powder companies consider "acceptable", if I recall.

I suppose you could get by without a scale using fixed-cavity metering devices (Lee dippers, Auto-Disk). Many have done just that with carefully-practiced dipping technique. You would definitely have to stay away from the bottom and top of the range. I would absolutely not use a variable-cavity measure without a scale.

Me, I think a scale is a small price to pay for having peace of mind, not to mention fingers and eyes.

Mikeinkaty said:
The Hodgdon web site says max load for a 125 gr bullet using Titegroup powder is 5.4 grains. That means the powder cavity would only be 1/3rd full. Would that be a problem?

No problem. You just reach the pressure limit before you run out of case volume, which is the case for most cartridge/powder combos.

You can use fast powders for light target loads. Titegroup won't be as light as the fastest powders, but more mild than the slowest.
 
Would you please clarify this a little? After your first sentence are you talking about Titegroup or Trail Boss. It's almost impossible to overcharge a case with Trail Boss but any more than the few grains that it takes to make a maximum load with Titegroup will blow up a pistol.

Also. What caliber is being loaded with the Lee kit? There should be a chart with the kit that tells how much of each powder a particular scoop throws. They are conservative, so if you follow the chart with the proper powder/bullet combo, it should be safe. For example, my .38 Special Lee Handloader kit came with a scoop that was supposed to throw 2.8 grains of Bullseye for a 148 gr wadcutter. I checked it with a scale and it throws 2.7 grains of Bullseye (with my leveling technique) which is fine with me. That is well under the max load for .38

I also have a whole set of Lee scoops that comes with a big slide chart thingy. I still check each scoop with each powder against a scale so that I know exactly what I'm getting.

UPDATE: I think I see your point. Yes, A double charge of Titegroup would only fill the bottom of the case but will blow a gun to smithereens. It is EASY to double charge with a fast powder.

I've been loading 38 Spl and 357 mag cartridges with 3.5 gr of TB and 125 gr cast lead coated bullets. My Lee charger works good for that. Nice light load and fun to shoot. Shot 200 of them Wednesday. But, thinking ahead to when I run out of 158 grain/1200 fps factory loads. Wondering what powder to use for that. Can't get enough TB in the case for that. I just found the Lee VMD table and am looking for the bulkiest powder that will work. With a 3" barrel I figure I'll need a fairly fast powder.
Thanks for your assistance. I'm only asking questions here that I have not answered elsewhere. Took a long time to find the VMD table!
 
Some powders are position sensitive, many are not. Stick to a powder or bullet manufacturer's load data and you will be safe.

Some powders have special rules:

WW296/H110 NEVER reduce loads below starting data!!!

Black powder, always compress the load. For reduced loads, fill the space with a wad or filler, like Cream of Wheat.

Trail Boss, NEVER compress the powder. It should have 1/16" to 1/8" space below the seated bullet base. My best accuracy occurs with a 1/16" space.

Please note that terms change over time and with technology changes, keep abreast of current loading information. One of the oldest examples is: Before the invention of Nitro-cellulose based powders (Smokeless powder) everything used was simply called "Gunpowder" and was safely interchangeable. After Alfred Nobel's discovery- not so much!

Ivan
 
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