Powder weighing problem?

Discussion in 'Reloading' started by emmagator, May 24, 2011.

  1. emmagator

    emmagator Well-Known Member

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    Ok, I'm using RL19 with my 270wsm with a 150gr berger. All the data I've read says that this combo should have a max load of 60gr @about 3000fps. I'm currently at 62gr and have not reached 3000fps, however I'm getting no pressure signs. I'm using a rcbs 1010 scale. This has to be a scale issue right?
     
  2. Gunpoor

    Gunpoor Well-Known Member

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    I don't know if your scale is accurate or not, and maybe you need to get a scale weight and check it. Published velocities are usually higher than my loads chronograph them at. You will have to decide whether the loads you are developing are safe and sane. I have exceeded written load data with some loads and with other rifles in other cartridges couldn't get near published max without getting signs of excessive pressure.
     

  3. dig

    dig Well-Known Member

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    To many factors to determine. Barrel Length? Custom barrel? Chamber? Free bore, Temperature?

    How close are you? what is the barrel Lenght is where I would start.
     
  4. emmagator

    emmagator Well-Known Member

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    Factory tikka 24" barrel. Im getting 2800fps with a 62gr load. Im new to all of this, however i am not seeing any signs of pressure. That being said im not an expert reloader either. Are there any subtle signs of pressure i can look for? Its just that im not getting any of the obvious pressure signs.
     
  5. Kevin Thomas

    Kevin Thomas Well-Known Member

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    emmagator,

    No, it absolutely does not have to be a scale issue. You can verify the scales accuracy with a set of check weights, but my guess is, you'll find it's accurate. There's a host of other things that are likely in evidence here, beginning with the powder, the primers, the chamber or trhoats of your rifle and at least a dozen others, including your chronograph.

    Have you compared this data against what's listed in other sources? This is precisely why I recommend that you have a good collection of reloading manuals avaialbel to you; it allows you to do some comparisons. If you do, you'll quickly see that there's quite a wide variety of velocities and charge weights shown between the various manufacturers. What one shows as a max load may well be a mid level load in another. They're both correct, but are correct in the particular component combination they used in their respective rifles. Change any element of that combination, includign just the case or powder lots, and you've changed the equation.

    Don't get too stuck on chrono velocity figures. They're useful bits of information on the whole, but they need to be regarded in context of a broader picture. It's just one piece of the puzzle.
     
  6. ken snyder

    ken snyder Well-Known Member

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    scale concerns: 4-way level surface, proper zero and looking at the pointer from same place every time. Generally advertised velocities are a bonus, not a fact. 150 fps under is nothing unusual, pretty hard to demonstrate any actual real life differences in the field as well. Some rifles don't know they're supposed to show stereotype signs of high pressure. The beginnings of excess is generally a random occurence, a bunch of no signs with an indicator thrown in once in a while. different lots of primers and powders and actual physical conditions can and will turn that ocassional sign into a stuck bolt or to some degree even worse. Over looked signs are accumilative: excess barrel erosion and short brass life. It is totally possible to reach disaster before this happens, but if my brass will not last at least 6 reloadings without doing anything fancy to it, the powder charge quickly goes on a diet. Inconsistant velocities do not always occur with over pressure loads but can be a sign as well. I think I have the good habit of leaving the extra velocity in the powder can and saving my wallet in some cases it could be saving my face as well.
     
  7. emmagator

    emmagator Well-Known Member

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    so if I'm reading this right, your saying its possible to not have pressure signs until its to late?
     
  8. Kevin Thomas

    Kevin Thomas Well-Known Member

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    I think he's saying you need to pay attention to the sum total of a variety of pressure signs, which is damned fine advice. Some cases don't show certain pressure signs as readily as others, due to a variety of factors such as case geometry or action type. Take them as a whole, collectively, and don't get too focused on just one sign.
     
  9. emmagator

    emmagator Well-Known Member

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    Now I'm getting kinda worried. I'm not seeing any signs that I have read and researched about, but I'm worried I'm overlooking something.
     
  10. Kevin Thomas

    Kevin Thomas Well-Known Member

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    If you're not seeing any pressure signs in a bolt gun, you're probably just fine. It's a much bigger problem in guns that operate at pressures are so low they don't show signs until you're well over their allowable limits. Lever actions like the M94, revolvers, pumps, that sort of thing. You can sail right into dangerous territory without being aware of it because many of these operate at pressures far lower than those of typical bolt guns. Sounds like you're doing fine, just keep a look out for the usual suspects; flattened or cratered primers (and they'll lie to you, too), shortened case life due to primer pockets opening up, that sort of thing. Sticky bolt lift is a fairly sure and certain sign that you've gone too far and need to back off; stay below that.

    You'll be okay.
     
  11. ken snyder

    ken snyder Well-Known Member

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    Too late? Sometimes yes! The common over pressure signs are a sign that over pressure is occuring not an indication that it is not occuring. The warning to work up to maximum loads slowly is good advise. Some cartridges like the .243 already exist in the high pressure zone without any additional help. Some primers will take more pressure to exibit that flattening effect. Some die, and chamber fit dimensions will not allow case stretching, a little bit of case sizeing wax left on the cartridge will reduce the feel of a starting to get a bit sticky bolt. Any over pressure sign is a need to evaluate what is happening. Sometimes over pressure signs are an indication that something isn't correct and completely absent of over pressure. Is a load combo that generally shows no signs of over pressure a good reason to overlook the 1 in 2 dozen rounds that does. That 1 time a quick follow up shot isn't so fast because the bolt didn't operate smoothly. In any case I don't feel that the few extra fps gained by takeing it to the border line is of any value in even the slightest. Problems are often attributed to reloading practices which is a nice way of saying things that are not too flattering to the person operating the press. -- keep in mind that safe pressures are obtained by testing hundreds and even thousands of rounds in all conditions, not merely 10 rounds fired on a nice fall afternoon
     
  12. emmagator

    emmagator Well-Known Member

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    So your saying I can't work up a safe load without firing a thousand rounds, wow, thought that's what manuals are for. I don't know many guys that can shoot those kind of numbers to work up one round. You make it sound as if I'm just dumping powder in the case. I loaded up the max published load for my setup and was about 500fps off published numbers. I've done hrs of research and reading.
     
  13. BuckSnort

    BuckSnort Well-Known Member

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    500 fps off? Sounds like a chronograph issue...

    Hard to read someones demeanor on the www... But it seems to me like Ken Snyder is trying to help you not criticize you..
     
  14. ken snyder

    ken snyder Well-Known Member

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    Emmagator published data has already gone through all the testing I need to feel confident that a midrange load is a safe place to start. Once I leave published data I'm on my own. Published numbers are believed to be safe and representative of reasonable care and advice A warning is given in every manual. It is true that many exceed maximum listings for published data with no ill effects, but an individual rifle will not allow its personal pressures to be exceeded without doing something not desireable. As I approach max listings or even exceed them I am very careful of random occurence and have very often found that a once believed good and no bad signs load to readily demonstrate undesireable characteristics at a later time and without warning. Some will say its a temperature related problem or some other concern, For me it boils down to border line, no signs given until they happen, the reasons this occurs is
    under my control. 500 fps is an interesting concern, is there any genuine thing reguarding pressure that I a fellow shooter can maturely comment on. I have seen only twice 500 fps slower velocity, 1 time a bonafide mislabeled barrel and the second time was a mistaken cartridge identification ( shooting his buddys similar looking cartridges). My Wild Cat cartridges and personal experiences In testing them leads me to a different understanding as to what is safe and even what is readily observable with limited testing and I don't want to get away with it until I wont. I definately do not want a missed opportunity because my need for speed pushed my cartridges into the oops category and by my own hands as well.