Experts, please help with Ammo issue.

[mikgarus]

I called Winchester ammo as they have different numbers. I was transferred to a woman named Kristin and she was great to talk to about my brass issue.
Do you happen to have the phone number?

[thermaler]

I shoot several different belted magnum calibers and am always on the lookout for brass. One of the problems encountered with belted magnum cases is that the case just above the belt swells and a regular full length sizing die won't correct that. I found a collet die made specifically to reduce the case diameter at the belt. Here is a link to the website that I got mine. http://www.larrywillis.com/ The collet die is the third item on his page. I use it after about every third loading on belted magnums and I use it with any fired cases I get from other sources. It paid for itself in recovered brass for me in short order.+1 I watch for the same propensity for significant flow in that area. I haven't had any problems with my 300 win mag reloads so far--but also routinely retire them after 3 shots. I'm going to get one of these belted magnum collets sooner or later.

[LongRange]

Reposted bellow.

[LongRange]

I started looking at the collet die and many say it's not needed...even from those that own the die. I'm torn if I should spend the $100 on the die.

you dont need that die....im not knocking it or anything im just saying you dont need it just get a quality body die and save $70 bucks...if this is a hunting riffle set the die to bump the shoulder back about .003-.004 if its a target riffle .001-.002 because you want the cases to fit tight as it helps reduce large FPS spreads...body dies are designed to size the body and bump the shoulder and have much tighter tolerances than the FL sizing dies and the bottom of the die is machined for the belt so yes it sizes the entire body.

http://www.midwayusa.com/product/420044/redding-body-die-300-winchester-magnum

another thing is buy quality brass if you can...ive shot every brass made for a 300wm and nosler is hands down the best...brand new winchester brass lasted 5-6 loads,new FC and remington lasted 3-5 loads before the primer pockets wouldnt hold a primer anymore.
also an easy way to see whats going on with your brass is to chamber a piece of unloaded unprimed brass thats giving you problems and open and close the bolt a few times WITHOUT extracting it then extract it and look at the brass...you will see shinny gold rings where the problem is as the problem area/areas will rub inside your chamber.the biggest thing to watch for on belted cases is the shinny gold ring right where the belt meets the case as that is where the case stretches the most.in the pics bellow you can see the ring im talking about from the inside...those are nosler cases that were loaded 15 times and the primer pockets are still tight and i could probably get a few more loads out of them but id rather not take the chance 3" from my face.

i know its a crappy pic but you can see the ring right at the tip of the bullet and how the case is much thinner at that ring...at some point the head will separate from the case and that $100 dollar die WILL NOT stop or cure that problem its just what belted cases do.

http://i1239.photobucket.com/albums/ff515/LTT-/Mobile%20Uploads/photo-5.jpg (http://s1239.photobucket.com/user/LTT-/media/Mobile%20Uploads/photo-5.jpg.html)