Who makes good brass for the 7mm rem mag?

[188MULE]

Looking for info on where to go for good brass for the 7mm remington mag?
I am currently loading winchester brass, I cut the primer pockets and deburr the flash holes. I do not weight sort or turn the necks, I've heard win necks are not very uniform, but the brass seems to be working as far as accuracy is concerned. Current groups are under half inch .415 for five. My rifle has a match chamber.
Would weight sorting and neck turning improve accuracy? I'm happy with how its shooting now but my main problem is that my neck tension is gone after 2-3 loads.
Would annealing remedy the neck tension problem, or are the cases worth all the effort? Where do I go for better cases?

 

[Moman]

Just taking a stab at this. Do the case mouths look or feel brittle? I have some Nosler brass in 308 that is getting this way and I plan on annealing them before any more loads.

As far as your accuracy is concerned, it sounds like you're where you should be.

 

[41mag]

Well I have used Remington, Winchester, Federal, and Hornady, take your pick, in my rifle they all shoot about the same as far as accuracy. That said, I find different issues with each brand after a few loads.

With some, the pockets seem to loosen up really easy, others stretch lengthwise excessively to the point I only get a couple of loads, some as you mention seems to get loose necks or excessive spring back, which I haven't tried annealing yet.

Overall the most used in my loads is Winchester, with Remington being right there along side. The accuracy load in my rifle will shoot both brands into nice 3/4" or so groups at 200yds using the 162gr Hornady SPBT.

If your set on Win or have a large number on hand, go ahead and pull out 10 or so and do the anneal on them. At least you will find out if that is the issue. Lets us know what you find out.

 

[whitely]

I really like the Norma brass for the 7mm. The flash holes are drilled, and the pockets are nice and uniform. There is very little prep that needs to be done. I have shot mine 5 times, and there hasn't been any head expansion, and I only had to trim them once, even with near max loads. The volume of the Norma cases was slightly larger than the Federal cases I was using, so I ended up add 1 gr. of powder to produce equivalent velocities.

I would just anneal your cases. I bought a "pencil" tip for my propane torch, and picked up some Tempilaq 650. I put a little of the Tempilaq on the inside of the neck, and then annealed the cases (neck and a little of the shoulder only), until the Tempilaq melted. This turned out to be around 7 seconds with my setup per case. Doing this should restore your neck tension.

 

[188MULE]

Thanks for the info, I have around 500 win brass right now but preping the cases takes alot of time and when you can get only 2-3 loads out of a case that sucks.
I don't always have as much time to reload as I would like, so if I would have to spend more for norma cases to cut my reloading time a may have to do that. Any more info would be great.Thanks.

 

[Moman]

188Mule, what type of resizing die are you using?

 

[Ol'Gator]

can't imagine only 2-3 reloads. what are your loads?

 

[188MULE]

I'm using a RCBS gold medal bushing die. Currently I'm am using the .306 bushing. Tension with this bushing is just right.
My load is 67 grains H4831SC at 3065 FPS out of a 26" Broughton barrel with a 168 VLD, the pressure seems fine. The primer pockets are not loose, and the neck tension issue seems to affect about 50% of the brass when loading the brass for the third time. I sort them when seating the bullets, at 100yds they group the same but I haven't shot them any farther out or chronographed them.

 

[Moman]

I was just wondering if you were overworking the brass. Is the .306 much smaller than the neck diameter of your loaded rounds?

 

[188MULE]

I used the method they referred to in my dies instructions which gave me the .306 for the bushing I also have the .305 & .307. This is the only bushing die I've used so I may be on a learning curve. The instructions say to measure a loaded round = .309 subtract .002 to .003 = .306 or .307. I'll have to try my .307 bushing and see if that would remedy my problem. Thanks.

 

[Moman]

Sounds like you're getting it narrowed down. I'm not sure about those dies, but I think you may need to go the other way (.305) for more neck tension. It also sounds like you may have a neck concentricity issue where the bushing is working on some of the brass but not all of them. Good luck!

 

[188MULE]

Thanks for the info and help, I think I've found the start of my problem.
The first run of brass ran right around .309, but I only measured a few to order my bushings. They all seemed to have about the same tension when seating the bullets.
I had just purchased a .305 to try to tighten the necks on the cases that felt loose but haven't tried this yet. This week I started loading with a different run of brass, still winchester, the bullets seated hard. The outside of the necks on a loaded round were around .310. After seeing the differences I measure the necks by spinning them in my mic and these case necks are not very consistant. So my next step is to get the equipment to turn the necks and measure them properly, or try out some norma brass.

Thanks for the help

 

[Moman]

I went round and round with Win brass for my 300 WM. I couldn't stand the lack of concentricity with it. I complained to Winchester about it and they replaced it with a new lot, it was even worse. This was about two years ago. I was a little more than fed up so I shelved the brass and bought Norma. It was great brass. Very concentric and well worth the money. I highly recommend it.