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Posted: 1/15/2010 8:04:10 PM EDT
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What should I expect for consistency?
I carefully weighed 30 powder charges of IMR 4895. Large powder charge bar. I was trying to dial in a 37.3 grain load. Out of 30 powder charges (with no adjustments), the loads averaged 37.53 grains. However, the drops break down like this: 5 charges were 37.3 4 charges were 37.4 5 charges were 37.5 10 charges were 37.6 5 charges were 37.7 1 charge was 37.8 Is this within a "normal range?" I was expecting a little more from the Dillon. While all values are within a decent range from a safety and functionality standpoint, I'd like to know if anyone can give me a little info on this. |
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I have been loading 45 acp and my charge has never been off by more than 1 tenth. I know that some powder will measure more consistently than others. I am using Winchester 231. After the tube has been empty and I refill I will tap on the side for a minute, I think this helps the powder settle and I always get very consistent loads. Maybe somebody has more advice but I think 5 tenths is too big of a spread. Make sure you are pulling the handle the same way every time try for the same speed and always full top to full bottom. |
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AVG = 37.55
SD = 0.187 N = 30 I would say those are normal. I don't think you'd too much better with any powder thrower in the world. You could buy a Harrel's for $400 and end up doing no better. You can do better with better technique but it will never be perfect (no variation). When I throw Varget, IMR4064 and other extruded powders using my 550, I get about 0.14 gr as my standard deviation. Thee are ways to improve upon what you have, a little, but you are doing fine. What were you expecting? Why did you think you would need that? |
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http://forums.1911forum.com/showthread.php?t=154783 I polished the insides of the powder measure like above, l also give a tap to shake the IMR sticks to keep them from bridging. I run a ground wire, alligator clipped to my powder measure, and wipe the inside with a dryer sheet I can run +/- .2 a gain variance ball powder meters perfectly through my Dillon's |
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Quoted:
AVG = 37.55 SD = 0.187 N = 30 I would say those are normal. I don't think you'd too much better with any powder thrower in the world. You could buy a Harrel's for $400 and end up doing no better. You can do better with better technique but it will never be perfect (no variation). When I throw Varget, IMR4064 and other extruded powders using my 550, I get about 0.14 gr as my standard deviation. Thee are ways to improve upon what you have, a little, but you are doing fine. What were you expecting? Why did you think you would need that? Actually, I expected to keep within a tenth either way. With scant experience in reloading, I guess my expectations were higher than necessary? I hadn't thought this would be as variable, that's all. Obviously, consistent charges would tend to give more consistent results, on target. While I will probably never work up to the maximum published loads for certain ammo, such variation might not be a good thing at those "upper" levels. It just tells me, if I'm going to work up a truly consistent load, I'd better be prepared to measure each load separately. To answer another poster's question, while I have generally used a beam type scale, all the stats are from my recently acquired Dillon digital scale. On another note, the ball powder for my pistol ammo seems to be more consistent. Thanks for the number crunching and info |
| I would check 30 charges using the beam scale. Electronic scales wander, especially when they are warming up. Even lights and breeze will screw with them. Also, I assume you were using the large charge bar, not the small one, correct? I can't figure how you would throw a 30+ grain charge with the small bar, but? |
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I loaded 9000 rounds of 223 the other day using factory primed brass and new bullets on a 1050. The powder is a ball powder similar to TAC or H335. The charge varied about +/- .2 grains. You will get a variance that is higher once in a while. But over hundreds or thousands of rounds +/- .2 or .3 grains is fine for blasting ammo. Anymore than that I start looking for an issue with the powder measure. When loading precision loads I use my single stage press. |
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Quoted:
Actually, I expected to keep within a tenth either way. With scant experience in reloading, I guess my expectations were higher than necessary? I hadn't thought this would be as variable, that's all. Obviously, consistent charges would tend to give more consistent results, on target. While I will probably never work up to the maximum published loads for certain ammo, such variation might not be a good thing at those "upper" levels. It just tells me, if I'm going to work up a truly consistent load, I'd better be prepared to measure each load separately. To answer another poster's question, while I have generally used a beam type scale, all the stats are from my recently acquired Dillon digital scale. On another note, the ball powder for my pistol ammo seems to be more consistent. Thanks for the number crunching and info When throwing pistol charges, you are throwing less powder. 0.2 gr out of a 5-10 grain pistol charge is much worse than 0.2 gr out of a 37 gr rifle charge. I have done direct comparisons between hand weighed charges and thrown charges. There is no statistically significant improvement in muzzle velocity when using hand weighed charges - NONE. There aer many variables at play affecting muzzle velocity. Powder charge is only one of them. They all blur together until the total is indistinguishable from the constituents. However counter-intuitive this may seem, it is a fact. I've done the testing several times, in several different rifles using several different cartridges. I use good equipment and statistically valid sample sizes (20 or more of each type). I forgot to mention this minor point earlier. My 550 is box stock - no reamed powder funnel, no polishing of funnel, no chain down the powder die. Here's a tip for reloading. Try it a few times. Make your reloading area quiet. Throw a charge and leave the handle down. Listen for the powder to fall. It takes time to fall, not a lot but more than just bang down, bang back up. Give it that time. It is not a race. This has improved the consistency of my throws on my 550. |
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When I first got my Dillon 550 I thought the powder measurer was going to work perfectly. It does work, for some powders and other powders not so good.
Like many folks, I like Varget for my .223 but there is no way the Dillon powder measurer is going to meter Varget consistantly...enuff. I'm thinking that type of powder measurer like what we get with our Dillon stuff is a compromise. Powders with the consistancy or grain like H335 and Win 231 it meters plenty good. Varget, IMR 3031 and other long grain type propellents, forget it. On the other end, powders as fine as Win 296 you can forget that too. As I understand there are items and/or modifications that can be made to your Dillon PM that will allow for more consistant metering useing the above mentioned propellents and the like. For me, my brother bought one of those new fangled electronic digital measurers a Lyman 1200DPS3 that turned out to be a little too new fangled for him so he gave it to me. Now I use that for powders that aren't compatible to the Dillon PM. -VonBarky- Edit to add below link which probably isn't hot, just copy past. http://www.arredondoaccessories.com/category.cfm?cid=1005,2023&PID=fc25l4901dqgdu&gid=PD |
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Quoted:
What should I expect for consistency? I carefully weighed 30 powder charges of IMR 4895. Large powder charge bar. I was trying to dial in a 37.3 grain load. Out of 30 powder charges (with no adjustments), the loads averaged 37.53 grains. However, the drops break down like this: 5 charges were 37.3 4 charges were 37.4 5 charges were 37.5 10 charges were 37.6 5 charges were 37.7 1 charge was 37.8 Is this within a "normal range?" I was expecting a little more from the Dillon. While all values are within a decent range from a safety and functionality standpoint, I'd like to know if anyone can give me a little info on this. With extruded powder, that's about what I would expect from a stock Dillon PM. With flake I get + or - .1, ball powder measures exact. I polished several of my Dillon PM's, it really cut down the variance with Varget. RE-15 measures almost as good as ball. I would suggest you try a ball powder, maybe Tac. IMR-4895 is a great powder, but I gave it up. Good luck |
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Managing static electricity, mechanical drag on parts, and ensuring your measurements are very accurate are all good steps to ensuring you're getting accurate and consistent powder charges. Another step is to make sure EVERY cycle on the press is as identical as possible, including any sort of "english" you put on using the powder measure.
On a single stage setup, I very deliberately operate the lever on the powder measure; firmly "whacking" the lever to the "fill" stop, pausing and then firmly "whacking" the lever to the "drop" stop. Consistent operation means every throw will have the same mechanics, allowing all the above steps to work even better. With a progressive, it's the same, but it's important to incorporate the "english" into the progressive's operation. While I could probably operate the lever on my progressive much faster than I do, I do the same sort of deliberate "to the stop" movements on the lever that I would on a powder measure to get the same sort of results. |
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polish
when the handle is up tap the clear plastic tube of the powder measure with your hand. not as hard as you'd [borat] "high five" [/borat] tap it enough to get all the powder sticks to drop through and settle. slowly crank the handle, take a full second, and pause at the bottom, like the poster above said, listen to the IMR stick to pour, they take time. tap it again. raise the handle tap I've heard of guys rubber banding an electric tooth brush to vibrate the powder down, but I've never tried it. a tenth of a grain or two is nothing to obsess about. try dropping a few 168HPBT match bullets on your digital scale. OMG they can vary too. Ball powders meter meter VERY well BLC-2, AA2230, Win 748, ect. |
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While there certainly is a lot of angst over small .1 to.3 variations in the powder throw among reloaders - you can rest your mind with the knowledge that with the volume of charge that you are throwing, that the variation is in the 1% to 2% of the total charge range (i.e. 37.3 grains). It is impossible to see any effect on accuracy with such an insignificant amount of variation.
Why? Simply because powder doesn't always ignite exactly the same way from each case, so any tiny amount of charge variation is lost. Plus, when we are looking for an accurate load, we're trying to match the powder charge with the vibrations of the barrel. Usually a few tenths either way won't affect this much - especially when you shoot a whole lot of groups, rather than just a couple that we often do when testing. The more you shoot, the more things even out. Therefore you are good to go - so start reloading! 
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To get the best consistency out of the measure, you'll need to stroke the press as consistently as possible. I tap the metal body of the measure for each charge. One time, I throw 50 charges and recorded the weights of each, taking notes on any stroke that was rough, bumped or whatever. I found that I could spot the bad charges after examining the data, so now I just toss them without even checking. |
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There's an outfit that makes a "tent" that goes over the OEM molded-in bar in the Dillon powder measure. I've bought bought a few.
While the OEM Dillon has a vestigial bar, I can say that the same contraption made a whale of a difference in unifority of powder throw on my RCBS powder measure, which had nothing at all. I think such a device worthwhile on every powder measure. |
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Quoted:
There's an outfit that makes a "tent" that goes over the OEM molded-in bar in the Dillon powder measure. I've bought bought a few. While the OEM Dillon has a vestigial bar, I can say that the same contraption made a whale of a difference in unifority of powder throw on my RCBS powder measure, which had nothing at all. I think such a device worthwhile on every powder measure. So you are describing a powder baffle. I installed a powder baffle in my Hornady PM, it made a difference there. The Dillon PM has a small one as you say, I never thought of adding another........Hummm. Off to look for one. Thanks for the tip. |
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Powder Baffle for Dillons . . . . http://www.uniquetek.com/site/696296/product/T1278 |
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Quoted:
What should I expect for consistency? I carefully weighed 30 powder charges of IMR 4895. Large powder charge bar. I was trying to dial in a 37.3 grain load. Out of 30 powder charges (with no adjustments), the loads averaged 37.53 grains. However, the drops break down like this: 5 charges were 37.3 4 charges were 37.4 5 charges were 37.5 10 charges were 37.6 5 charges were 37.7 1 charge was 37.8 Is this within a "normal range?" I was expecting a little more from the Dillon. While all values are within a decent range from a safety and functionality standpoint, I'd like to know if anyone can give me a little info on this. That is normal. I would not worry about it, Just weigh one every hundred rounds or so. 4895 is a long grain and is the cause of the fluctuations. H-4895 is just as good and meters better. ALso look at the new 8208 which will be a wonder powder and it meters as well as ball. |
| Dillon specifically warns against using IMR powders in their powder measure. The truth is IMR powders are the hardest to throw consistently on the market. The other truth is it doesn't matter. Extruded powders seem to work well in spite of the fact they can't be thrown to +/- .1 grain. That's why I use them almost exclusively now. They fill the case better and usually provide stellar accuracy. They are very forgiving to powder weight variance, if you are shooting 600+ yard tournaments, hand weigh each charge for long range. |
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Excellent info all!
I did happen to repeat the excercise using both the Dillon Digital and a pretty decent beam scale. The throws are generally more consistent than my first data set. I didn't get the wide swing in weights. They pretty much stayed within 0.2 +/- grains. on both scales. That's pretty decent, from what I gathered here. -ppknut |
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