Q: I have a couple of queries about reloading different .308 cases. I shoot big bore and the rifles I use are a Mauser Mark X with 770mm stainless steel barrel and Omark Model 44 with a 670mm barrel. We are limited to certain powder and projectiles we can use in competition. I have Winchester, Remington, Federal and Lapua cases. I’m using AR2208 powder and CCI 200 primers. My load in Winchester cases is 45.5gn of AR2208 Nosler 155gn Comp. HPBT or 155gn Dyer HPBT and CCI 200 primers. If I use the same load in other cases, the primers seem to flatten out more, so I’ve tried dropping the load by half a grain. ADI Reloaders Book lists the starting load as 44gn and maximum as 47gn compressed. It may sound silly, but I always weigh every load and shake every round to hear if the powder rattles. It does in Winchester brass with 45.5gn, but not in the other cases. Firing the 45.5gn charge in all brands of brass cases, they are not hard to extract. My questions are: Is the velocity from Rem. Fed. and Lapua cases using 45gn of powder the same as, or close to what I am getting with 45.5gn in Winchester cases? Do you think I should try another powder? I’ve been told that I have to have enough velocity to reach 1000yds, punch round holes in the target and not keyhole. Oval-shaped holes won’t score. Would it make any difference if I had to change primers as I can’t always get CCI 200? About 20 years ago I used AR2206 with 144gn military bullets and found it was good, but we aren’t allowed to use military bullets any more. Would this powder be a better choice? Can you suggest a load that would develop the same velocity in the different brands of cases?
Kym Sloper
A: Different brands of cartridge cases vary in construction, hence in weight and capacity. Judging by your letter, the Winchester cases you are using hold more powder than the other brands. This is why the primers are flatter in those other cases than Winchester because chamber pressures are higher. However, if extraction is not stiff, the pressure in the different cases is not excessive. It’s a waste of time shaking cases to see if the powder “rattles,” especially if charges are compressed. There’s no way of telling what the velocity is in any of those cases without chronographing each load. I doubt if reducing the charge by 1/2gn would make any noticeable difference, but one or two grains less might. You should be getting plenty of velocity with a charge of 45.5gn of AR2208; I’d guess about 2990fps in that long 770mm barrel. The maximun charge of 47gn of AR2208 is heavily compressed. No other powder produces as much velocity in the .308 as AR2208. Your load should punch round holes at 1000yds. I’ve never experienced any problems with changing primers, but why not buy a good supply of CCI 200 primers? AR2206 was discontinued years ago and replaced by AR2206H, but I suggest you carry on using AR2208. There is no load that will give the same velocity in cases that have different capacities.
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