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THIS IS A TEST!  Industry standards are welcome but the intent here is to pole the forum members to find out what they think.  rogerOld age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone.. | ||
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Well to me I call case capacity as the total gross capacity. Available capacity is the net. IE: the gross less capacity lost by the bullet taking up space. Nosler for example calls load density the volume of powder divided by the capacity "available " with the bullet seated to max saami specs. With a flat based bullet I used to have a chart showing water cpacity for different dia vs length. Now days I let the computer program calculate it. Gross capacity I use a weight full of water less weight empty. As usual just my $.02 Paul K | |||
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I have always considered case capacity to mean volume up to and including the shoulder. The neck is for the bullet. If The bullet doesn't fill the neck then I gain - if it protrudes past the neck then you lose! (I don't ever seat past the neck and I don't want a rifle that requires it - that's just me). Regards 303Guy | |||
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Lyman's 47th Reloading Handbook recognizes neither term. That can only mean that the concept is illegitimate.  ________________________ "Every country has the government it deserves." - Joseph de Maistre | |||
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Never heard of available case capacity, only case capacity which is the total volume of the case, all the way to the mouth of the case. I measure it in terms of grains of water held by the case when filled to the top, all the way...  | |||
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I see it the same way.  My experience is that the Quickload program is conservative, as one can always get a bit more powder in, or to put it differently, when it shows a 100% full load with a specific bullet, you will find you can still get more powder in the case. I think it has also to do with the specified figure as to case capacity in its database. Different brands of cases have different capacities for the same cartridge. For example when you open up the 300 Win Mag you will find 4 different options to pick from based on a certain brand of cartridge case. In other cases they just use one figure without specifying which cartridge case. If we have to put a meaning to 'available case capacity', then it can only be done in relation to a specific bullet that would erode some space of the total capacity, hence a figure that would differ each time a different bullet is being loaded. Warrior | |||
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Yep that is why it is needed. A light weight bullet will take up a lot less case capacity than a long heavy one. One of the major complaints many had against the 284 was a heavy bullet had to be seated so deep it used up capacity reducing the space available for powder. A load that has no compression with a light bullet could be 105%+ with a heavy one. When you simply take a capacity say at the base of the neck or start of the shoulder you are taking an approximate available capacity. Better than using a full case for sure. Quickload gives you a Maximum case capacity to overflow, volume occupied by the seated bullet, and Useable (available in my book) capacity. Those are in grs of water. Taking that capacity converting it to powder causes some of the confusion. Water doesn't compress powder does. Actually you reduce space between the grains. So when you do things like using a drop tube, shaking the case, even slow dropping the powder you will get a slight increase in powder over what is normally called a 100%. Yes as was stated capacity will vary with brand of brass. In the case of Quickload just increase the overflow capcity up or down the usuable will adjust. In my young years when I was doing a lot of wildcat work I would also weigh available capacity. First I would take a case and measure total capacity comparing the weights with and without water. Then take the same case and drill out the bottom. Then the bullet design in question seated to just clear the boattail or until you got to a smooth area. Weigh the case with water. Seat the bullet deeper and redo. You then have the amount of capacity that bullet uses per a given amount of seating depth. You can then adjust the capacity for any given seating depth for that bullet. Normally that number could be used for the same bullet style for a given manugfacturer. For example the 140,160Nosler BT. As usual just my $.02 Paul K | |||
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Rodger this is how I thunk of it answering 1 and 2 1. what is meant by case capacity. A. max amount of H2o a case will hold. 2. what is meant by available case capacity. A. real world capacity using each mfg case and real powder and being able to seat a bullet. | |||
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Quickload has different cartridges for 300 Win Mag, depending on who made the brass, because case capacity varies. When I measure some of those brands, my results are not only different, the hierarchy of capacity is different. What does it all mean? The case capacity not only varies from brand to brand, but within a brand over the years. | |||
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I haven't had to be tested in awhile , fun Roger !. Case capacities are based on the approximate weight of plain water measured in grains which can vary slightly from different case manufactures for any given size case !. Available case capacities generally means Load Density Load density is the determining factor in selecting powder for a particular rifle cartridge with averages being 86% density just about ideal in most cases. Load density is the ratio between case capacity and actual powder charge. Most factory ammunition is loaded with a density of 80% - 90% of the cartridge case capacity. Powder charge weight divided by case capacity equals load density. Say a Powder charge 40 grains divided by Case capacity of 50 grains = .8 or 80% load density. Measuring case capacity . Once you have established your bullet with it's seating depth in your chamber Weigh one case with bullet seated to proper depth without powder or primer. Fill that case with water through the primer hole using a syringe or submerging it in a pan of water until all the air is gone now place a small piece of tape over the primer hole and weigh it again. Now subtract dry weight from the water weight including tape and this will give you your case's capacity. | |||
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A plethora of great responses. A good show of brain work rather than letting "Authority" dictate definition of words. Any other words of wisdom?  rogerOld age is a high price to pay for maturity!!! Some never pay and some pay and never reap the reward. Wisdom comes with age! Sometimes age comes alone.. | |||
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Q U I C K L O A D i am too lazy to do the math opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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Any other words of wisdom... Ya don't piss into the wind.  | |||
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Nope - not even close -- h335 fills a case better than 3031 -- so "case capacity" as measured in powder is meaningless across powders but the rest, if using water at meniscus, is accurate opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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OK, so you don't like my interpretation of case capacity. Why keep us in suspense to your answer? Or the correct answer? I'm probably already getting an incomplete for not answering question #5. | |||
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The problem with this is it lacks consideration for compressed loads. I can fill a 30.06 case to the mouth with Re22 and seat a 180 bullet, compressing the powder, and it still be safe. I have used all available "case capacity" for this given load. Ted Kennedy's car has killed more people than my guns | |||
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That's fair comment. In my 'definition', it's the volume not the weight of powder in consideration. So, load density to me means the amount of powder loaded over the amount the case will hold up to the neck. Any powder that fills the neck is over 100% (with or without compression when the bullet is seated). What I am really interested in is how much free space is left after loading. This influences my choice of powder. For some illogical reason, I want the powder to fill the case up to the bullet base - if possible. So for that reason, I try to relate to the 'available' case capacity (and think of it as actual 'capacity' - which it is, really. The neck is there to hold the bullet, after all). Interestiung thread, bartsche. Quite fun!  Regards 303Guy | |||
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Dave - You measure case capacity, expressed in grains of H2O, (use at least 3 cases to average) by resizing a FIRED case, leaving the primer in. weighing it, then filling it with water+meniscus, and weighing it again. The difference in weight (an, average) is the case capacity. This is a primary data source. "available case capacity" Which sounds like a good technical term, is NOT fixed, and is not even fixed for a given bullet, due to seating, and CERTAINLY has no value across bullets. This is a "red herring" phrase, and is so highly variable it is at best a guide. It's not fixed .. in fact, like CENTRIFICAL force, it is a misnomer. Its measured by the volume of the cylinder, as it would displace that volume of water, expressed in grains. all that being said - quickload, once given the actual capacity and actual bullet information, keeps me from making math errors. opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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Some of you on this forum may not be of the age to remember when there were NO Home computers !. I went through college with a slide rule the first time and still know how to use it . Scary huh !!. In my second phase of college nearly 21 years later we had CALCULATORS and computers !!!. Wow what a difference that made , stone age too space age so to speak . The key is not whether you use a loading program or a loading manual slide rule or even a computer . The Key is UNDERSTANDING HOW to archive the correct answer by which ever means are available to you !.  | |||
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