Posted: 2/5/2007 8:26:02 AM EDT
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Question for you reloading gurus. How important is headstamp in the brass that you sort? I spent the Super Bowl sorting 4.2k brass and I have come up with about 5 major types In order of volume LC=lake city Rorg=Radway green Wcc=Winchester cartridge company Pmc=? Rp? Now these are the major ones, I also found some others in there. Random ones from Winchester, remington, hornady, malay mil surp etc but these all told equal about 300. How important in your mind is headstamp when making ammo? Is there a large enough difference in a mid pressure load to make a dangerous pressure spike? Am I being too anal about this? I also found 8 berdan primed bastards in there. I shouldnt be breaking any pins while sizing this batch! |
| Realistically it's not all that important for .223 unless you are loading match grade ammo and then you want absolute consistency. As a matter of principle I separate my brass by headstamp because it gives me a chance to inspect everone of them for dents, cracks, expanded primer pockets, etc. For that reason alone it's a good reason to separate your brass. I just finished separating a few thousand rounds myself so I know what a time consuming PIA it is. One thing I noticed is that ADCOM brass is shit just like their ammo. It appears to be softer than the other brands because the headstamp gets marred up pretty bad after shooting it. I think the brass is reloadable for one or two times but thats about all I would trust it for. |
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You said that you are going to be using mid pressure loads so you should be fine. If you want to exercise your can't be too cautious side you could take a couple of cases from each head stamp and check them for capacity Different makes/years will have differing internal case capacity. That leads to pressure variations for the same powder charge when using mixed headstamps. This isn't good for accuracy, although it's not typically horrific, but it can be very bad when your near maximum pressure load that is fine in brass A finds itself in brass B that has 5-20% less internal capacity. Now you have a way overpressure load. In my book mixed brass is fine for plinking and or training ammuntion that doesn't necessarily need to be a firewalled load but for best accuracy and or SHTF ammuntion the brass needs to be sorted. PMC=Pan Metal Corporation R-P=Remington Peters |
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Different brands of brass have different thicknesses of case wall, and thereby different capacities. This is the most pronounced in the military cases (LC, Radway etc), which also tend toward heavier heads to help reliability in machine guns. So a "standard" charge from one of the cook books will give higher pressures in military brass than in commercial, occasionally quite a bit higher. So, yes, sorting does make a difference. And if you have the ability to measure the internal capacity of the cases in cc's of water (at the same temperature), the closer to uniform the case caqpacities, the more uniform the groups from that group of cases. (Of course, this is only important if you're going to shoot a match, and not if you're going a-bumpin' at the pit.) PMC is one of my favorite brands of ammo-- www.pmcammo.com. "RP" is Remington-Peterson. 
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All the advise above is very good. What I do is sort the Radway 92,93 into one group and load my plinkers. 25gr H335 BTW When I load for my 24" bull barrel I use once fired (in the 24") WCC. If I ever run out of Radway brass I will sort the brass I have cleaned into makes and load in groups by manufacturer. I weigh each year head stamp and see if I can use two or three together. Good luck and always weigh after trimming to a set length. |
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Sorting is necessary, especially for accuracy and safety sake. Every piece of brass gets inspected prior to reloading. Check for bulges, dents, cracks, signs of excess pressure, case head separation, etc. Sort and cull. Match shooters weigh and measure everything. Cases, bullets, powder. Never weighed a primer myself, but I have weighed the others. Reload 20 rounds each of the same loads in the different casings. Mark these casings with nail polish or sharpie marker on the case head, sharpie is best. Fire and repeat, say 5 or 6 times. Check for accuracy and durability of cases. If you find that RORG and LC brass are comparable in the loads you roll based on accuracy and longevity, lump them in together in your brass. If there are any major differences, keep them apart. At the end of 5 or 6 loadings, you might see some startling differences, like cull rates and how the cartridges wear out. Track the differences. All of the other advice given is spot on. |
If you look at the following Excel file:www.ar15barrels.com/data/223weights.xls You will see that most of the brass casings (military & commercial) wiegh pretty much the same. I asked the same question on the Maryland AR15 Shooters website and the reply I got was that the 10% weight difference applied to .30 caliber brass and not .223. The Excel spread sheet tends to confirm that. There is also the probabillity that different case wieights between different headstamps could be due to the weight difference of different alloys and not necessarily due to the thickness of the case. Case in point: If you look at Malaysian brass (headstamp MAL) you will see that it noticably has more copper than the other brands. I haven't weighed it yet to see the difference but it wouldn't surprise me if it is different from the norm. Same for ADCOM because it is noticable softer than all the others. I don't know if this is due to a difference in alloys ot lack of heat treating. The difference in case wieght doesn't necessarily mean that the brass is thicker it could be heavier due to different alloys. |