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September 21st, 2011
 Norma has announced a recall of certain lots of Norma 217 powder, product # 20932175 (500gr cannister). According to Norma: “The present batch of 217 powder is recalled as it can give high pressure under some circumstances. We hope to have a good batch available later this autumn.” Norma 217 is commonly used for magnum cartridges. Norma describes 217 as a “flexible magnum powder, suitable where there is relatively large case volume in relation to the bore size.” Norma has not yet published the lot number(s) of the affected 217 powder batch.
If you have some 217 powder and are concerned whether it is subject to recall, contact Norma at:
Norma Precision AB
670 40 Åmotfors Sweden
Tel: +46 (0) 571 315 00
Fax: +46 (0) 571-315 40
Web: www.norma.cc
Story Tip by Edlongrange.
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September 13th, 2011
 Are there significant metallurgical differences in the alloys used in various brands of cartridge brass? The answer is yes, and we have proof. Using a state-of-the-art X-Ray Fluorescence Spectrometer, some tech-savy Wisconsin shooters recently analyzed the alloys in seven different types of cartridge brass.
The test results revealed significant differences in the percentages of copper and zinc in the different brands. Copper content ranged from a low of 72% by mass (Winchester, S&B) to a high of 80% by mass (Remington). Zinc, which adds hardness to the alloy, ranged from a low of 20% by mass (Federal) to a high of 36% (‘brown box’ Lapua). Interestingly, the tests, as reported by Forum Member Fred Bohl, revealed that the alloy in the new ‘blue box’ 6mmBR Lapua brass is different than the alloy in Lapua’s older ‘brown box’ 6mmBR brass. Specifically, the ‘blue box’ 6mmBR brass has more copper and less tin (by mass). Here’s a summary of the X-Ray Fluorescence spectrometry tests:
This testing was done at major science laboratory, using high-grade X-Ray Spectrometry Analyzing equipment. Fred reports that: “The data was run by one of the club members with the permission of the test lab supervisor who is also a club member and shooter. The data in original output reports was far more detailed about trace elements at lower orders of magnitude primarily from surface contaminants (some were rerun after establishing a repeatable cleaning procedure)”. The testing process is discussed in this Shooters’ Forum thread.
We do NOT have the metallurgical expertise to infer that any particular alloy shown above is “better” than another. The alloy “blend” is merely one of many variables that can have an impact on the performance and quality of the finished product. Annealing times/methods differ and some cartridge brass is extruded while other cartridge brass is made with the traditional drawing process. Readers should not presume, on reading the above chart, that they can identify the “best shooting” brass simply based on the constituent metals in the various alloys.
General Observations about Cartridge Brass Alloys
With the cartridge brass X-Ray Spectrometry results in hand, Fred Bohl hoped to find out what “real world” conclusions (if any) we could draw from the raw data. Fred sent the test results to some knowledgeable metallurgists, soliciting their comments. Fred explains: “When I first posted this information [in the Shooters’ Forum], I had hoped to elicit replies from expert metallurgists and to initiate a useful discussion. From [their replies] I distilled the following ‘consensus’ comments”:
1. The range of Copper/Zinc ratios suitable for use in cartridge making by typical processes is 85/15 to 65/35 (% by weight or mass).
2. The range of Copper/Zinc ratios suitable for use in cartridges intended for reloading is 80/20 to 70/30. Above 80% copper, the resulting case would tend to be too soft and difficult to attain the distribution of hardness desired (harder at the base and softer at the neck). Below 70% copper the resulting case would tend to be too hard, would work harden too quickly and require frequent annealing. [Editor: That said, the ‘brown box’ 6mmBR Lapua brass, with 62% copper/36% zinc content, enjoys an unrivaled reputation for both accuracy and its ability to perform well after a dozen or more reloading cycles. We know 30BR shooters who have shot the same old-style Lapua brass (6mmBR parent case) more than 50 times. So maybe the “expert” view needs re-thinking.]
3. As the percentage of zinc increases, the tensile strength, yield strength and hardness tend to increase. However, above 35% zinc, while tensile strength will continue to tend to increase, both yield strength and hardness will tend to begin to decrease.
4. The trace additives of iron and/or silicon are used to control the processing characteristics of the alloy. Trace additions of chromium will improve corrosion resistance and give a shinier surface (both largely cosmetic).
5. Selection of the alloy and additives is a trade off among: end use desired properties; processing time and yield; and cost of materials. For example, the classic 70/30 cartridge brass was considered an optimum combination of corrosion resistance and hardness for single use by the military with good process yield at acceptable material cost.
6. All of my responding experts were surprised by the brown box Lapua alloy except for the oldest. He remembered using an almost identical alloy late in WWII when copper was in very short supply for military small arms ammunition.
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July 1st, 2011
Norma has updated and enhanced its website at www.norma.cc/en/ (the ‘en’ is for English version). Among the many new site features is Norma’s “Ammo Academy”, a technical resource that provides information on: Ballistics, Powder Storage, Barrel Wear, and Bullet Expansion. In addition, the Ammo Academy now links to Norma’s Reloading Data Center, where you’ll find loads for nearly 70 cartridge types including: .223 Rem, .22-250, 6mmBR Norma, 6XC, 260 Rem, 6.5-284, 6.5×55, 7mm-08, .270 Win, .284 Win, .308 Win, .30-06, 300 Win Mag, .338 Lapua Mag and dozens more.
The Ammo Academy’s Ballistics section contains some fascinating technical facts:
- After the trigger is pulled, it takes around 0.005 seconds before the firing pin reaches the primer.
- From the firing of the primer it takes 0.0015-0.002 seconds until the bullet exits the muzzle.
- When the bullet leaves the muzzle, the hot gases surround and overtake the bullet, continuing the acceleration for a few centimeters.
- Because the barrel is always angled slightly upwards, the bullet’s flight starts about 3-5 cm below the line of sight.
Norma also offers some good advice about Powder and Cartridge Storage:
To maintain the product quality for as long as possible, you have to keep the powder in a suitable place under suitable conditions. Where possible, store the powder at a constant temperature, ideally between 12 and 15°C (54°F to 59°F), and a relative humidity of 40–50%. If the air is too dry, it will dry out the powder, which will cause the pressure to be higher, thus affecting performance. Also make sure that you close the powder container properly afterwards. Cartridges should be stored under the same ambient conditions to maintain their quality.
For more info on Norma products, CLICK HERE to access Norma’s Catalog Download Page.
Story Tip by EdLongrange. We welcome submissions from our readers.
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February 3rd, 2010
Today we wrap up our coverage of the 2010 Shot Show. Jason and I visited scores of booths, inspected hundreds of new products and interviewed dozens of industry insiders and “old friends”. We can’t package all the highlights into a single blog post, but here are some “short takes” on SHOT Show items of interest — the new stuff we really liked and some odd but noteworthy elements of the “Shot Show Experience”.
Most Important New Technology — Burris LaserScope
AccurateShooter.com doesn’t give product awards, but if we did, the new Eliminator LaserScope from Burris would be a leading candidate for “Best in Show” honors. This unit employs modern technology to make the shooter’s job easier. A built-in laser rangefinder finds the distance to your target. Then the scope consults a ballistics table, pre-programmed for your cartridge. The scope’s “brain” calculates the precise holdover for your ranged target distance and displays a bright, red dot on the vertical cross-hair. That dot is your calculated correct point of aim. Just put the red dot on the target and squeeze the trigger. For a varmint hunter, this scope could be the best thing since sliced bread. Shoot all week and never touch the elevation knob. We just wish the Eliminator was offered in a higher-power version — say a 6-24×50. Currently the Eliminator is offered only as a 4-12x42mm optic. The Eliminator is far from perfect, but its technology really could render other conventional hunting riflescopes obsolete.
Important Brass Developments
For Benchrest shooters, the big news was Norma’s introduction of 6 PPC brass. According to Lou Murdica, who has tested the early production brass, this new brass is “outstanding” and is fully competitive with cases fire-formed from Lapua 220 Russian brass. Norma’s production of 6 PPC brass demonstrates that the Swedish company is very serious about benchrest shooting and the American market. We had a long, productive conversation with the CEO of Norma, and we could tell he is committed to expanding Norma’s place in the American market. Expect some major developments in the months ahead, including a joint project with AccurateShooter.com. Norma also showed us the 300 Norma case which we feel will eventually be an important chambering for long-range shooters. This case has “just right” capacity to drive the 200+ grain, high-BC 30-caliber bullets.
Unnoticed Excellence — The Barrel-Makers
Flashy new products get the media attention at SHOT Show every year. But we think the most important “back story” involves American barrel-makers. If you want to do a story on EXCELLENCE in today’s gun industry, you need to focus on the elite barrel-makers. Companies such as Bartlein, Broughton, and Krieger continue to make better barrels every year, with new features such as gain-twist rifling, and 5R rifling. Just this Friday, I witnessed a .308 “tactical” rifle with a new Krieger 5R barrel fire two successive three-shot groups that were each just a ragged hole — and the first two out of three shots in each group literally went through the same hole at 100 yards. And that was during barrel break-in with an untested load and untrimmed brass “right out of the box”. America’s top “boutique” barrel-makers are now producing extraordinarily good products, yet they are rarely mentioned by the popular print gun magazines. At a time when we see recall notices from companies such as Ruger and Remington on a regular basis, our American custom barrel makers are building the best barrels in the world, indeed the best barrels ever made.
A Contrast in Style — American vs. European Optics-Makers
Among the major optics makers, the difference between American and European marketing styles was painfully obvious. Leupold and Burris had fast-talking, glad-handing salesmen, who, for the most part, knew very little about their product line and even less about optics engineering. By contrast, Zeiss and Schmidt & Bender staffed their booths with real optics engineers with Ph.Ds, many of whom were directly involved in the design of the products on display. At Zeiss we spent nearly an hour talking with Stephan Albrecht, the German engineer in charge of the new 20-75X Diascope spotting scope and the new Diavari Flourite riflescopes. During our conversations with Stephan he actually solicited our feedback, took careful notes and promised to explore some of our suggestions. We also were able to share our field test results directly with Eric Schumacher, President of Carl Zeiss Optical, USA. By contrast, Leupold’s decision makers and top-level engineers were nowhere to be found, and when we voiced our (now annual) plea that Leupold stop building scopes with canted reticles, we were greeted with nothing but blank stares. Leupold’s reps couldn’t comprehend the canted reticle problem, even after I pulled a scope (with 3° canted reticle) off their display rack and showed them.
Federal FCPA Sting Rocks SHOT Show
In the mainstream media, SHOT Show 2010 will be remembered for one thing — the “Big Bust”. On January 20th, FBI agents arrested 22 gun industry employees and executives for alleged violations of the FCPA (Foreign Corrupt Practices Act). Those arrested, including one of Smith & Wesson’s Vice Presidents, were charged with trying to bribe FBI agents posing as African government officials. This “high-visibility” bust culminated a DOJ sting operation two years in the making that involved 250 federal agents.
Accuracy… Who Needs Accuracy?
There’s a curious thing about SHOT Show. It’s touted as the greatest gunshow in the galaxy, but one thing is sorely missing — really accurate rifles. Heaven forbid there would be a true benchrest rifle or rail gun on display! Many of our readers own more true 1/4-MOA rifles than you’ll find at the entire SHOT Show. We know this is a trade show, but still you’d think somebody would want to show off a really impressive rifle — say the National Championship-winning F-Class rifle or a record-setting rail gun. It would be like having a Top Fuel dragster on display at a car show. But no, what we have instead are acres upon acres of 1-2 MOA factory guns. That’s disappointing to say the least. It’s sort of like going to an air show only to discover the Blue Angles have cancelled and there won’t be any jets at all.
 Pop Stars vs. Legendary Marksmen
At every SHOT Show, I’m struck by some odd ironies. This year I walked past one booth which was absolutely mobbed with people trying to meet an attractive young female celebrity — a contestant from American Idol. Fighting through the throng, I continued down the aisle to the McMillan booth. There was David Tubb, quietly chatting with a McMillan rep. Mind you, David is an 11-time National High Power Champion. He has also won National Silhouette titles and scores of other matches. He is arguably the greatest competitive rifle shooter in American history. Yet hundreds of people walked by without even noticing David. Think of the irony. Imagine if Michael Jordan was sitting in a booth at a sports convention. The place would be mobbed. Yet David has certainly dominated his sport the way Jordan dominated basketball. Jordan won six NBA Championships. Tubb has won ELEVEN National Championships (and he’s not done yet). Yet the vast majority of SHOT attendees don’t seem to care about legends like David Tubb, or about shooting excellence in general… they would rather wait in line to meet a “wannabee” from American Idol than learn something from a truely legendary marksman. Sometimes I DO wonder about our priorities.
Too Many Black Rifles?
After Obama was elected in November 2008, there was a surge in demand for semi-auto, military-style rifles, partcularly AR-platform rifles. Manufacturers of all sizes, from Remington/Bushmaster, to small fabricators, ramped up production of AR uppers, lowers, and complete rifles. Now, 15 months later, demand is slacking off, and there is an over-abundance of ARs. We perceived a notable lack of interest in AR rifles at SHOT Show, unless they had some new bells and whistles. Retailers seemed much more interested in big-bore bolt guns and handguns, or in the completely new semi-auto designs such as Remington’s ACR.
Bring Back the Convention Center
For 2010, SHOT Show was hosted at the Sands Expo Center, behind the Venetian Hotel complex, instead of the Las Vegas Convention Center. On paper, this seemed like a good move. The Sands Expo is nearer the strip and closer to popular hotels. In practice, the Sands Expo proved a poor location for SHOT Show. Outside the main hall, booths were crammed into conference areas with low ceilings and bad lighting. A very large number of exhibitors were assigned to the first-floor “Dungeon”. There, access was difficult, the lighting was bad, and low ceilings and concrete floors worsened the background noise problem.
Just getting into SHOT show was a challenge. For the majority of visitors staying in hotels on the strip, one had to walk through the maze-like interior of the Venetian to get to the Show. This was annoying to say the least. On 3 out of 4 days I took at least one wrong turn, and on Day 2 I got thoroughly lost. I saw plenty of folks with SHOT Show badges walking in circles, completely disoriented — the Venetian is a building where you can’t walk in a straight line for more than 150 feet or so. And once inside the SHOT Show proper it was very easy to get lost as well. Pete Brownell was heard to say that he needed a map just to find his own booth.
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January 20th, 2010
 At the request of AccurateShooter.com, respected Benchrest ace Lou Murdica tested the brand new, early production Norma 6PPC brass. Lou shot 30 cases (both turned and unturned) over the past few days, and he endorses the Norma brass without hesitation. Lou says “the Norma PPC brass is great brass. Without a doubt this will be highly competitive brass in the short-range benchrest group”. Lou did observe that the necks on the Norma brass were slightly thinner than on Lapua 220 Russian brass, but that really doesn’t matter. With a slight neck turn, Lou declares, “the Norma PPC brass is as good as any out there.”
Lou said, based on his testing, the Norma brass holds pressure well, and the accuracy is outstanding. Lou shot five 5-round groups, as in a match course of fire, and his largest group was “around 0.148″ at 100 yards.
If you’re a short-range benchrester, definitely watch this video and listen to Lou. He thinks this new Norma brass will “change the game”. Note — Lou said most PPC shooters can shoot the Norma cases with no change in their powder recipes. So you won’t lose any velocity using Norma’s new brass. Lou was very impressed with Norma’s new offering, enough so that he declared: “I would go right for the Norma right now if I could put a bunch in my hand.”
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December 21st, 2009
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This is potentially big news for short-range Benchresters and for varminters who shoot PPC variants. Norma has resumed production of 6PPC brass — at least on a prototype basis. NOTE: We don’t have many specifics. Norma has not firmly committed to exporting production 6PPC brass to the USA, nor has Norma announced a product release date. However, we received the following email today:
“After some work Norma has just started production of 6 PPC cases again. A new double-press has been installed which allows us to work-harden the case better. Internal tests are promising and we wonder if you would be interested to test a bunch.”
That’s it… we’ve shared all that we know for now. |
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May 5th, 2009
Ken Brucklacher, current President of the Original Pensylvania 1000-yard Benchrest Club (Williamsport), joined the immortals this Sunday, May 3rd. Shooting a .300 Weatherby Mag with 240gr Sierra MatchKings, Ken set a new 10-shot Heavy Gun World Record score of 100-8X. The group size was pretty amazing too. A measured 3.137″, Ken’s ten shots also set a new group record at the Williamsport range, besting the previous mark set 13 years ago by John Voneida (3.151″ and 100 score). Brucklacher’s group is just 0.089″ larger than the 3.048″ all-time, 1000-yard small group shot last month by Joel Pendergraft.
Conditions were good when Ken set the record. It was cool, with overcast skies, and the winds were calm with “the flags still hanging down”. Ken said he “took his time, made sure he was on for every shot.” He pretty much held “on the center of the white patch” in the 1000-yard target. The result was spectacular, as you can see below:
Ken has been shooting 1K benchrest for 9 years, and in the past year his big Heavy Gun has been awesome. This new 100-8X record was not a fluke. Ken’s gun has already shot two 100s in competition. In fact, Ken set a 6-match, Heavy Gun 1000-yard World Record for score with his .300 Weatherby, averaging 98.333. In 2008, Ken’s Heavy Gun shot a 100.0 score in the 8th Williamsport 1K match, a 99.0 in the 9th Match, and another 100.0 in the 10th match of the year. That’s consistency.
Gun Specs: Aluminum stock, Lawton Action, Krieger Barrel
Ken’s record-setting Heavy Gun features a Lawton action in a John Buhay machined aluminum stock. Gunsmith Mark King (Duncannon, PA) built the gun and chambered the 34″ Krieger, 10-twist barrel as a .300 Weatherby Magnum with 0.339″ neck. The record group was set with a windage-adjustable rear rest. Elevation is set with the front rest. Interestingly, when shooting the record group, Ken was “holding dead center on the white patch”.
Record-Setting Load: .300 Weatherby Mag, 240gr SMKs, H4831SC, Fed 215Ms
Ken set the record with a .300 Weatherby Mag shooting 240gr Sierra MKs, seated 0.028″ off the lands. His load was 72.0 grains of Hodgdon H4831sc pushed by Federal 215M primers.
 Brucklacher used Norma .300 Weatherby brass “right out of the box”. You read that right… Ken set the record with brand new Norma brass with no case prep whatsoever. He didn’t touch the flash holes or primer pockets — in fact Ken didn’t even chamfer the case mouths. This was brand new brass, not fire-formed. According to Ken, he “just added a primer, filled the cases with powder, and shoved in a bullet.”
While Ken does not point his bullets or trim meplats, he did weigh and measure the 240gr MatchKings (base to ogive) before loading. Ken has not chronographed this load so he doesn’t know the velocity. Ken didn’t do any special load tweaking for this record group. However, he explained that he changed his seating depth last summer, going from .018″ jump to .028″ jump. That minor change, Ken noted, “really seemed to close up the groups”.
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September 10th, 2008
We’ve all heard the old adage: “Keep your powder dry.” Well, tests by Norma have demonstrated that even normal environmental differences in humidity can affect the way powders burn, at least over the long term. In the July issue of Precision Shooting Magazine, Fred Barker reviews the current Norma and Vihtavuori reloading manuals. Fred notes that, in the Norma manual, Sven-Eric Johansson, head of ballistics at Nexplo/Bofors, presents a very important discussion of water vapor absorption by powder. Johansson shows, with supporting test data, that the same powder will burn at different rates depending on its water content.
Powders Leave the Factory with 0.5 to 1.0% Water Content
Johansson explains that, as manufactured, most powders contain 0.5 to 1% of water by weight. (The relative humidity is “equilibrated” at 40-50% during the manufacturing process to maintain this 0.5-1% moisture content). Importantly, Johansson notes that powder exposed to moist air for a long time will absorb water, causing it to burn at a slower rate. On the other hand, long-term storage in a very dry environment reduces powder moisture content, so the powder burns at a faster rate. In addition, Johansson found that single-base powders are MORE sensitive to relative humidity than are double-base powders (which contain nitroglycerine).
 Tests Show Burn Rates Vary with Water Content
Reviewer Fred Barker notes: “Johansson gives twelve (eye-opening) plots of the velocities and pressures obtained on firing several popular cartridges with dehydrated, normal and hydrated Norma powders (from #200 to MRP). He also gives results on loaded .30-06 and .38 Special cartridges stored for 663 to 683 days in relative humidities of 20 and 86%. So Johansson’s advice is to keep powders tightly capped in their factory containers, and to minimize their exposure to dry or humid air.” Confirming Johansson’s findings that storage conditions can alter burn rates, Barker observes: “I have about 10 pounds of WWII 4831 powder that has been stored in dry (about 20% RH) Colorado air for more than 60 years. It now burns about like IMR3031.”
What does this teach us? First, all powders start out with a small, but chemically important, amount of water content. Second, a powder’s water content can change over time, depending on where and how the powder is stored. Third, the water content of your powder DOES make a difference in how it burns, particularly for single-base powders. For example, over a period of time, a powder used (and then recapped) in the hot, dry Southwest will probably behave differently than the same powder used in the humid Southeast.
Reloaders are advised to keep these things in mind. If you want to maintain your powders’ “as manufactured” burn rate, it is wise to head Johannson’s recommendation to keep your powders tightly capped when you’re not actually dispensing charges and avoid exposing your powder to very dry or very humid conditions. The Norma Reloading Manual is available from a variety of sources, including MidwayUSA.com.
| Real-World Example — “Dry” H4831sc Runs Hotter
Robert Whitley agrees that the burn rate of the powder varies with the humidity it absorbs. Robert writes: “I had an 8-lb. jug of H4831SC I kept in my detached garage (it can be humid there). 43.5-44.0 gr of this was superbly accurate with the 115 Bergers out of my 6mm Super X. I got tired of bringing it in and out of the garage to my house for reloading so I brought and kept the jug in my reloading room (a dehumidified room in my house) and after a few weeks I loaded up 43.5 gr, went to a match and it shot awful. I could not figure out what was going on until I put that load back over the chronograph and figured out it was going a good bit faster than before and the load was out of the “sweet spot” (42.5 – 43.0 gr was the max I could load and keep it accurate when it was stored in less humid air). I put the jug back in the garage for a few weeks and I now am back to loading 43.5 – 44.0 gr and it shoots great again. I have seen this with other powders too.
If you have two jugs of the same powder, one kept in a room in your house and one somewhere else where it is drier or more humid, don’t expect the two jugs of the same lot of powder to chrono the same with the same charge weights unless and until they are both stored long enough in the same place to equalize again. Been there … done that!” |
Do Your Own Test with Sun-Dried Propellants
Johansson studied the effects of humidity variances during long-term storage. Keep in mind that a powder’s water content can change in a much shorter period of time if it is exposed to extreme heat, or if it is used in a very humid environment. You can do your own simple test to show how heat can de-hydrate powder. Throw 100 grains of powder and weigh it. Then put it out in direct sunlight for a full day (shielded from the wind so you don’t lose any kernels). Re-weigh the sun-dried powder. You’ll find it has lost a bit of weight from the water baking out.
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