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!