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Posted: 11/23/2010 10:53:12 AM EDT
| How many cases do you prep at a time for match loads and if you sort by weight, how much variation is ok? |
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You'll probably have to go through the weight sorting exercise on your own to find out whether it's worth your time. (It's not for short range ammunition.)
200 cases prepped and segregated will serve for 600 yard slow fire ammunition unless you are shooting matches every weekend. There are many benchrest guns around that have no more than 50 cases prepped, and its common to see guns for sale that include 20 cases fitted to that gun. That works for the shooter that loads between targets. |
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F-Class 1000m competition is 20 rounds. So, you probably need...25 rounds just in case. You can buy 100 rounds of Lapua brass and hopefully find 25 that weigh the same.
You will sort by weight and the weight difference for the ones you choose will be ZERO. If would be even better if you can measure the difference in the volume of the case...which would also be ZERO. |
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Quoted:
I'm shooting national match and highpower at two local clubs where the longest targets will be at 300 yards. I shoot the same courses and the 200/300/600 yd ones. For brass, I start with 1,000 or 1,500 pieces of LC (same year). Next is cleaning/sizing/deprime/trimming/swaging/cleaning again. The weight sorting is done by the average weight: A) +/- .1 gr, B) +/- .3 gr, C) avg -.4 gr and less, and D) avg +.4 gr and higher. The "A" group is used for slow fire prone at 600 yd, the "B" group is used for 300 yds, and the "C" group is used for 200 yds. The "D" group gets used last and is usually for standing practice. Either the "A" or "D" group are much better than just taking a random group since either has none of the much lighter or heavier cases. After weight sorting a couple of dozen cases, if you notice that the median of the group is much above or below the average, toss them back in the can and readjust your your median weight. |
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I usually do 5K of the same year/headstamp, then weigh them into batches of 1 tenth of a grain.
I start at the bottom of the weight and add brass from the next weight up when I lose them or enlarge the primer pocket. It works out as you go that the first ones are replaced as you go up, the weight stays in the margin/group, so I always have brass that's close in weight. You really don't need to do this for the short line ammo. (300 yrds and under) 'Borg |
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Quoted:
I usually do 5K of the same year/headstamp, then weigh them into batches of 1 tenth of a grain. I start at the bottom of the weight and add brass from the next weight up when I lose them or enlarge the primer pocket. It works out as you go that the first ones are replaced as you go up, the weight stays in the margin/group, so I always have brass that's close in weight. You really don't need to do this for the short line ammo. (300 yrds and under) 'Borg Sir, for the most part I do much the same as you but this is the time of year that I like to do most of my reloading with the goal of not having to reload any more highpower ammo until after the Nationals each year. I buy most of my rifle powders at Camp Perry and now that there are no more matches locally for about the next three months I'll reload both short line (200-300yd) and 600yd ammo. I mostly work in batches of 500 .223 Rem. cases at a time because that's about the limit of my case tumbler. For the 600yd ammo I work up a batch of 400 cases at a time and at 22 rds per match that will definately last me through the year. For short line ammo I try to have about 1600 rds on hand before February which will last me through twenty-six 800agg. matches. The real answer to the OPs question is that it depends on how many matches I shoot between February and the Nationals in July/August. 7zero1, out. |
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I try to have ~4000 cases fully prepped at the start of the season so I can defer processing until Winter sets in. I tumble the fired brass in walnut when I get back from the range, then set it aside until free time is available; in the meantime, I spend as much time shooting as possible.
I did an experiment several years ago to determine just how much effect brass weight has on .223 loads. I used WW brass (sized, trimmed and deburred, primer pockets uniformed, flash holes deburred, and neck turned) , WSR primers, charges of RL-15 or N-550 powder weighed to 0.1 gr, and 75 gr A-Max bullets. Using the lightest and heaviest cases (sorted from 1000 once-fired I had on hand), I had two lots of 10 cases with a 3 gr difference in weight. The average muzzle velocity difference was 16 fps, just a bit more than the 12 fps due to 0.1 gr of powder. I choose to sort 0.5 gr lots of brass for my long range loads, but the effect will only matter at 800-1000 yards - the vertical displacement on the target from such a small velocity change is negligible at shorter distances. Unless you control all other sources of variation, the effect of brass weight is negligible. Since my .284 brass is heavier and larger in volume, I sort it into 1 gr lots; I'd also use 1 gr lots for similar cases such as the -08 and -06 families. |
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Quoted:
I'm shooting national match and highpower at two local clubs where the longest targets will be at 300 yards. 300 yards doesn't require case preparation like 600 yards or further does. I feel confident just uniforming primer pockets and shooting the same lot of brass at that distance. Weighing cases won't help. If you are really trying to get the best groups possible simply spin all your ammo to check for runout. Keep the best rounds for the last stage (22 rounds slow fire prone), that's the toughest target you'll face. I've tried this both ways (lots of times) and discovered I shoot just as well without going into minutia in the reloading process. I'll still do all the work for fulll size courses, but only for the 80 grain bullets fired at 600 yards. Everything fired up to that point is just load em and shoot them. I uniform primer pockets on all my brass, but that's it. |
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