Belted Magnum Cases and Resizing...

[Sgt_Jamez]

I have a 7mmRM, and have not reloaded for it much. My reading of various threads would indicate that using normal sizing dies makes brass bunch up at the belt. True? Do I really need a $90 Larry Willis die to get more than 2-3 loadings from my brass?

I read the other thread here about brass life on the 7mmRM and i couldn't come out with a clear road ahead. I have a set of Lee dies for it, but want the Forster Ultra mic seater and Redding Type S bushing...

So the real question is...

Larry Willis collet die?
Redding Type S Neck die + body die
Redding Type S FL die?

Please advise, thanks!

 

[ChrisGarrett]

Re: Belted Magnum Cases and Resizing...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sgt_Jamez</div><div class="ubbcode-body">I have a 7mmRM, and have not reloaded for it much. My reading of various threads would indicate that using normal sizing dies makes brass bunch up at the belt. True? Do I really need a $90 Larry Willis die to get more than 2-3 loadings from my brass?

I read the other thread here about brass life on the 7mmRM and i couldn't come out with a clear road ahead. I have a set of Lee dies for it, but want the Forster Ultra mic seater and Redding Type S bushing...

So the real question is...

Larry Willis collet die?
Redding Type S Neck die + body die
Redding Type S FL die?

Please advise, thanks! </div></div>

I've reloaded about 1000 7RM rounds using standard dies. I'm currently using a Redding body die, bushing neck sizer and a micro seater. Modern belted magnums have a belt that is cosmetic in nature and so you should headspace off of the shoulder, not he belt, ah-la the 375 H&H.

This all being said, you might have a bit of trouble (not me BTW) getting the case head area back down to snuff, but that's not been a problem for me and I'm on 4-6 reloads on the typical commercial brass headstamps.

I'd go with the flow and try the typical commercial dies and go from there. If you load 'hot', you'll probably have more issues with primer pockets opening up and case necks splitting, than you will with not being able to chamber the rounds due to an enlarged case head area.

Chris

 

[Sgt_Jamez]

Re: Belted Magnum Cases and Resizing...

Great thanks for the course correction!

 

[jrob300]

Re: Belted Magnum Cases and Resizing...

I have a 300WM. The Redding body die works great for me. I have some brass with close to 20 firings. Remember to use the paper clip tool to check for incipient case-head separation.

There may be some combination of chamber size and case pressures that require the collet die.

John

 

[Bigwheels]

Re: Belted Magnum Cases and Resizing...

I had the same experience with my 300Wm, but it wasn't a chambering issue that made me buy an IT collet die for the belt area, it was hard extraction. The FLS dies don't push the case back low enough, & after several firings it had expanded to where it would fit in the chamber, but would not want to come out after firing. The IT die cured this. I've since rebuilt my 300 WM with a match chamber, & so far have only 3 cycles on my brass, but haven't yet needed to do anything other than neck size. I have a bunch of old brass from my old chamber that has 8 cycles on it. I need to anneal, but other than that it's still GTG.

 

[desertHK]

Re: Belted Magnum Cases and Resizing...

I have a similar cartridge, but not the 7 mm RM. I have the 300 wm. Before I started using the collet die, after about 4-5 loads, the case doesn't chamber correctly because of the slight expansion just above the belt. Ever since I started using the collet die, everything works well. I am very happy with it. So to me, it's worth it. I do FL resize my 300 WM brass.

 

[Sgt_Jamez]

Re: Belted Magnum Cases and Resizing...

I loaned my bud the scope off my 7mmRM. I haven't shot the rifle in a while so the one set of reloads I have made are impatiently waiting the return of my scope so I can see what happens to my brass. For many years I never kept my brass, and now that I reload I shudder to think of how much brass I've tossed.

 

[RebelRouser]

Re: Belted Magnum Cases and Resizing...

I full length size my 7mag and have 4-5 reloads on the brass. No issues yet.

 

[johndoe]

Re: Belted Magnum Cases and Resizing...

I minimum full length size my brass with a Redding type s die.
I picked up the Larry Willis die but have not used it yet do to
primer pockets loosening up after about 5 firings. Hart makes a tool
to tighten up the pockets.