Reloading belted magnum cases

Mudruck

Mudruck

New member
Im getting ready to start reloading for a 7mm Rem. Mag. I swear that I read somewhere that belted mag cartridges have issues with separating above the belt.

Do any of you guys load belted magnum rounds and have you seen any issues like this?

Thanks
 
Yes, belted brass won't generally last as long as regular. I have gotten as few as 3-4 reloads out of (loaded hot) 300 weatherby brass.
 
I think it has more to do with magnum loads than belted brass. Any high intensity load is going to stretch brass more, thus giving shorter case life. If you loaded your 7 mag at old 7X57 pressures, the brass would last just as long. I load for my belted rounds the same as for any others.

You'll need to get a paper clip, straighten it, then bend just the tip to make a feeler that you insert into the mouth of the case and use to check for case head separation (I think that's what it's called). Maybe Jack or one of the old pros will chime in here with some more technical information about this technique. In the meantime, do a few searches here, I'm sure it's been discussed before.
 
That's a big 10-4 good buddy (haven't used that phrase in a long time) I've seperated a number of 243 cases over time. The hotter you load them, the sooner they are going to fail, Magnum or otherwise.

ps...I don't mean Over-loading either. Even staying under max the same holds true.

Also, I have Always noticed a bright "ring" around the case about 3/8 to 1/2 inch above the base prior to having one seperate. That is a warning sign from my experience.
 
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Seems that I've heard that one of the problems with belted mags is that with standard dies the body of the case ahead of the belt can not be resized inward, and that after a few reloads the shells may not chamber due to the side of the cartridge being too big around. I've also heard that someone makes a special die that has some type of an insert that resizes the side of belted cases. Again, a few searches here, should find a previous discussion or two about the topic.
 
I believe the die is made by Lee or Lyman. The cost is around $90. Thought about it but still haven't made the plung yet. I agree, belted magnums do have a shorter case life. Just the nature of the beast.
 
I dont own any belted magnum for that reason. The belted magnum headspace on the belt instead of on the shoulder as regular cases do. That means a very generous gap between case shoulder and chamber wall. That means the brass stretches significantly at each firing.

One way to extend case life is to neck size after first firing. Now case headspaces on shoulder as regular cases do and that generous gap is no longer there to over stretch brass.
 
Howard is correct that the cases need to be resized so they headspace on the shoulder not on the rim. Stretching and head separations are most always caused by resizing the shoulder too far. Most belted magnums need to be full length resized for easy chambering but the shoulder should be pushed back only far enough for the round to chamber easily. If you use a case shoulder length gauge(you should) do not push the sholder back more than .002" from what a fired case measures.

Jack
 
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