PrecisionRifleBlog.com A DATA-DRIVEN Approach to Precision Rifles, Optics & Gear
Related Articles
I’ve been using Norma’s brass for the 7mm Remington Magnum lately, and thought I’d write a review over what I’ve found so far.
Norma is a high-end, European brass manufacturer similar to Lapua. They use the highest quality raw materials, and have very narrow tolerances and tight quality control. Like Lapua, they drill the flashholes on their brass instead of punching them. Almost all other brass manufacturers punch their flashholes, which can cause inconsistency and require that you debur the flash hole.
Also like Lapua, Norma anneals the neck on all of their brass. However, that isn’t as apparent as it is on Lapua cases because they clean the brass after they do that. Annealing makes the brass softer around the neck, which can greatly extends the life of the brass. Think of a wire hanger … if you bend it back and forth enough times it will break. Brass is the same way, in that the more you “work it” (like bending the hanger), the sooner it will break. The annealing process essentially softens the brass in the area that you will work it the most, around the shoulder and the neck. This is also prevents gas leaks and enables the case to hold the bullet firmly for at least 10 years without cracking as a result of aging material.
Further down on the case body, the hardness increases to avoid unnecessary stretching. If it is too hard, it would bring the risk of cracks. At the base of the case, around the primer pocket, the the hardness is nearly twice that of around the neck. This not only ensures safety, but it also extends life by limiting primer pockets expansion over time.
The structure of the material reveals the hardness. During processing the large, soft grains are broken down into smaller ones, which makes for a harder material. At the annealing, small grains become bigger and the hardness decreases.
So what does this mean for brass life? I talked to Dr. Don Heath at Norma’s Sweden headquarters, and asked him what kind of life I could expect out of Norma brass with magnum loads. He said “We test each lot of cases and ensure they reach 10 loadings at CIP maximum pressures before we send them out as component brass. Of course, our test barrels have minimum chamber.” He did also say that the Rem Mag was especially hard on cases, but if you loaded them to 80-90% of the published min/max range (as I do), then he would still expect 10 loadings per case.
Update Feb 2014: I’ve now fired some of my Norma 7mm Rem Mag brass 9 times. 95% of the cases are still going strong. I plan to cut a few cartridges open after the next firing, and I’ll post photos here of what the case wear looks like. The 5% of cases I’m not including got loose primer pockets so I tossed them as that happened. That didn’t really happen on any of the cases until the 7th firing.
You have to pay a little extra for Norma brass, but their consistency and quality control process are worth it in my opinion if you are making match grade ammo.
Weight Variation Found in Bulk Package of 100 Cases
I recently weighed 100 pieces of brand new Norma 7mm Remington Magnum brass, and found exceptional consistency. Take a look at the results:
- Average = 215.03 grains
- Standard Deviation = 0.51 grains
- Average Deviation = 0.38 grains (average of the absolute deviations of the data points from the mean)
- Variance = 0.27
- Extreme Spread = 2.7 grains
- Extreme Spread as % of total weight = 1.3% (this is ridiculously low)
All data was gathered using a RCBS ChargeMaster 1500 Powder Scale, which is accurate to +- 1/10 grain and was calibrated right before use.
For match grade ammo, I only use brass that is within 1% of each other in terms of weight. Norma brass is very consistent, so this entire lot pretty much fell within that strict tolerance. I only culled the 5 pieces that fell on either extreme. That means 95% of the brass met my match grade standard … which is really, really good.
Weight Variation Found in Five 20 Count Packages
I just bought another 100 pieces of brand new Norma 7mm Remington Magnum brass, but was only able to find it in 20 round packages instead of a bulk 100 piece deal (all from the same lot) I was able to get from MidwayUSA.com last time. I was curious to see if the lot to lot consistency was similar to what I found in the original 100. The results were outstanding once again … here is what I found:
- Average = 214.84 grains (this was within 0.2 gr of the average of the first 100 I tested)
- Standard Deviation = 0.62 grains
- Extreme Spread = 3.5 grains
- Extreme Spread as % of total weight = 1.6% (still ridiculously low)
Norma vs. Lapua
Many people like to compare Norma and Lapua. I’ve personally measured a lot of Norma and Lapua cases, and my findings show that Norma brass has less variation than Lapua. In fact, the weight variation I found in Lapua case weight wasn’t even in the same ballpark as this Norma 7mm Rem Mag brass. It was actually very similar in to the weight distribution of some super-cheap, once-fired Remington 223 brass I bought for 1/5 of the price. Purely based on the emperical data I’ve gathered, Norma brass is more consistent than Lapua brass. However, I think both manufacturers are leaps and bounds ahead of all other companies, and both very capable of being used to load match grade ammo.
In fact, Lapua must believe the quality of Norma brass is close enough to theirs that they are willing to stamp their name on it. Here is a quote I was able to find from a Lapua rep when he was asked whether Lapua had ever made 7mm Rem Mag brass:
Actually, I don’t believe that Lapua has ever made 7mm Remington Magnum brass. There was a time when we offered 300 Win Mag brass, but this was also something that we didn’t manufacture; it was produced under contract for us by Norma. I think this may well have been the same situation for the 7mm Mag brass you’ve encountered. I’ll have to check with the Finns to make certain of this, but I’m fairly confident that this is what you’ve run on to here. They’ve generally had a fairly strong aversion to producing belted cases, and this is what makes me suspect that this is the case.
We have a 7mm Naturalis hunting bullet, but aside form that, the 7mm bore size seems to be a weak spot in our line. No surprise that the 6.5s hold more sway in that region of the world, but we keep trying to get them to broaden the 7mm offerings. In the meantime, whether the brass was produced by us or Norma, it should be good quality stuff either way. Enjoy!
Kevin Thomas
Lapua USA
Quote Source: http://www.longrangehunting.com/forums/f28/historical-question-lapua-7mm-rem-mag-brass-production-55654/
I am not a member, but I have found all my Norma 7MM brass to be TOO SHORT (2.480 or less)..
is this to be expected from Norma?? even after full size and fire-form again, all brass was under 2.480… comments, please??
Wow, that hasn’t been my experience at all. I’ve bought 500 pieces of Norma brass for the 7mm Rem Mag, and not only were they long enough … they were also very consistent in length. Perhaps you got a bad batch? I’ve got a bad batch of Lapua 223 Rem brass before, but I know they typically make really high quality, consistent brass.
Thanks for sharing your experience though … It’s helpful to know when that happens. Informed consumers can drive manufacturers to higher quality standards.
I’ve used Norma brass for years in my 7 MM Rem Mag. One thing that you did not touch on is that the Norma is much thicker than Winchester or Remington. I pay high attention to the case necks turning off the hight spots and use Redding bushing dies. Loaded rounds with Norma brass measure .0044 larger at the case neck than my Winchester brass which gives me a better case to chamber fit. I’m not knocking Winchester brass, I like it’s hardness and I use it in my current go-to hunting load. But the Norma is more consistent and has much thicker necks.
Yes sir. I actually HAVE to trim the necks slightly to fit them in my match chamber. I don’t have to do that for Winchester, Remington or Federal brass. Thanks for pointing that out. I did forget to mention that aspect.
Thanks,
Cal
i bought norma brass for my 7mm RM and broke 2 priming tools trying to insert primers. Contacted Norma, no reply from them. I will never purchase Norma again. Also broke my K+M pocket primer because the pockets were too tight.
Wow, John. That sucks. Sorry you had so many issues with the Norma brass. I’ve yet to have that experience, but I appreciate you sharing that with the rest of us. I’ll certainly keep an eye out for it.
Thanks,
Cal
The observations of the Norma 7mmRM are the same I’ve made with their 270W. I’ve ben using their brass for 30Years used in 5 different rifles over that time, and have probably 8-10 batches (3-400 cases?) in use (they are run until they split necks etc), but when all weighted, about 95% are with 2gns of each other. They seam to last pretty well to, but I only run “Warm” loads, rather than max loads. The neck thickness is reasonable consistent, but I’ve only worried bout that in the last few years.
Thanks for the input Russell. I’m also running “warm” loads (not max loads) on my 7mm Rem Mag and I’ve now fired the same cases 8 times and they’re still going strong. Norma told me each case is designed to be shot 10 at 95% max load.
I do neck trim that cases, and find minimal variance in the neck thickness … But, the main reason I neck trim is to get it down to fit my tight match chamber.
Thanks for the confirmation that Norma cases are performing to this same standard in other cartridges as well.
Cal I’m new at this game or LR shooting. I find it hard to find guys that use 7mm rem mag for target shooting. I’m getting into the sport because I love hunting and now that I live on the wide open prairie it seems like most of my shots are getting out around 300-500 meters. I have a target set at 500m and I don’t have much problems hitting it. However I have noticed that factory loads “suck” so I’m starting to reload my own. Is there any recommendations you can give me on bullet seating depth for the Berger 168gr hunting vld. Should I jump to lands or jam into.
Hey, Broc. There aren’t many guys using a 7 mag for target shooting. With target shooting you don’t need all the energy that it carries down range, so you’re just punishing yourself with recoil and shortening your barrel life. If you need to stretch out to 1200 to 1600 yards, it works well … but the 338 Lapua and other cartridges shine there as well.
Now, hunting is a different story. I’m still 100% convinced the 7mm Rem Mag is the best hunting cartridge for the type of hunting I do (open prairie scenarios like you described on deer-sized animals). I took a nice whitetail buck and a wild boar with my 7mm Rem Mag just a few weeks ago. Both went down with a single shot. I love that cartridge!
I do have a load for that bullet, along with the seating depth I use posted. You can view that stuff here: PrecisionRifleBlog.com’s Pet Loads. Now your chamber dimensions are likely different, so it may not translate exactly. But it’s what I’m running.
Thanks,
Cal
Hi Cal!
I just ordered some Norma brass for my 7mm Rem Mag Sako 85. What case neck wall thickness are you recording with the Norma brass? Also, what bushing have you had success with for these?
Thanks!
Colin
Hey, Colin. I have all the data for my loads published here, for future reference.
But, I’ve been neck trimming my Norma 7 mag brass to 0.012″ neck wall thickness. I use the 0.307″ Redding Neck Bushing. I did a little experimenting with different sizes, but that’s the one I thought gave the best results.
Good luck!
Cal