New Norma (non-belted) Mags
New, current or modern: .300, .338, and .375 (all non-belted). Classic, former, historic: .308 and .358 (both belted).
First, thanks to everyone that has been providing links, references and other information for a number of questions that I have thrown onto the GB Forums:
1) Competition Shooting and Reloading, and
2) Ask the Experts
One area that I had asked for input on actual, verifiable +/- effects of varying body taper, modification of position and angle of shoulder and the potential for improved characteristics with increased case base diameter and/or barrel length vs. "over-bore".
Another area of inquiry has had to do with the R&D work of Jimmie Sloan (and many others), regarding the current Norma Mags: 300, 338 and 375 (will there be a modern .358?) which are based or derived from the .416 Rigby brass/case.
Just in checking the basic case it appears that there is innate potential and one might well realize rather dramatic improved characteristics: powder burn, accuracy and transporting a heavier payload a needed or desired distance. There appears to be the potential that one could reach out further to touch something with more grains at a greater distance, with as good or better accuracy.
[[Base diameters of rifle Cartridge Families: .30-06 = 0.473, 7mm RM (and most belted mags) = 0.532, RUMs = 0.539, .404 Jeffery = 0.545 and then the .416 Rigby = 0.589. (The Lapua .300 and .338, I understand, and the new Norma use the .416 Rigby parent case. The most noteable(?) beyond the Rigby may be the .505 Gibbs = 0.640? Which is the parental case of a number of current wildcats.]]
I had previously seen quite a variation of the supposed case measurements which I suspected were alpha, beta, delta, and so on versions through the R&D process (and/or other folks working on the same or very simular sort of projects).
Sent an email of questions out to Norma. I was pleasantly shocked by their concise and timely response which I found to be generally helpful. The reply from from Norma and site information alludes to some variation of the case measuremnts, in the real world, at present.
I remain optimistic that I will be able to get specific info regarding the +/- effects of varying body taper, shoulder angle and the head spacing. (Not insignificant information - especially if one were interested in building such an animal from scratch today, rather than patiently waiting for a manufacturer to put something out there for us to purchase, this year, next or the year after.)
At this point, I have in mind several potential ways to pursue this; so I am ahead of where I was a couple of months or even a couple of weeks ago!
Regarding such a project I believe I need only: 1)- money (working on that), 2)- tie-in with a highly skilled, intelligent, knowledgable and dedicated riflesmith, and 3)- the actual specs and/or dies to get this underway ... So the day dreaming is pretty much behind, now it is the "simple" task of real world tasking!
I appreciate the interest and sharing of facts, figures, thoughts and ideas here on the GB forums. Gentlemen, thank you all and to:
Tailgunner 1954,
justC,
tsr 1965,
sand warrior, and as always
nononsense
And as before, I'm open more recommendations, suggestions and ideas if anyone out there has any?
First, thanks to everyone that has been providing links, references and other information for a number of questions that I have thrown onto the GB Forums:
1) Competition Shooting and Reloading, and
2) Ask the Experts
One area that I had asked for input on actual, verifiable +/- effects of varying body taper, modification of position and angle of shoulder and the potential for improved characteristics with increased case base diameter and/or barrel length vs. "over-bore".
Another area of inquiry has had to do with the R&D work of Jimmie Sloan (and many others), regarding the current Norma Mags: 300, 338 and 375 (will there be a modern .358?) which are based or derived from the .416 Rigby brass/case.
Just in checking the basic case it appears that there is innate potential and one might well realize rather dramatic improved characteristics: powder burn, accuracy and transporting a heavier payload a needed or desired distance. There appears to be the potential that one could reach out further to touch something with more grains at a greater distance, with as good or better accuracy.
[[Base diameters of rifle Cartridge Families: .30-06 = 0.473, 7mm RM (and most belted mags) = 0.532, RUMs = 0.539, .404 Jeffery = 0.545 and then the .416 Rigby = 0.589. (The Lapua .300 and .338, I understand, and the new Norma use the .416 Rigby parent case. The most noteable(?) beyond the Rigby may be the .505 Gibbs = 0.640? Which is the parental case of a number of current wildcats.]]
I had previously seen quite a variation of the supposed case measurements which I suspected were alpha, beta, delta, and so on versions through the R&D process (and/or other folks working on the same or very simular sort of projects).
Sent an email of questions out to Norma. I was pleasantly shocked by their concise and timely response which I found to be generally helpful. The reply from from Norma and site information alludes to some variation of the case measuremnts, in the real world, at present.
I remain optimistic that I will be able to get specific info regarding the +/- effects of varying body taper, shoulder angle and the head spacing. (Not insignificant information - especially if one were interested in building such an animal from scratch today, rather than patiently waiting for a manufacturer to put something out there for us to purchase, this year, next or the year after.)
At this point, I have in mind several potential ways to pursue this; so I am ahead of where I was a couple of months or even a couple of weeks ago!
Regarding such a project I believe I need only: 1)- money (working on that), 2)- tie-in with a highly skilled, intelligent, knowledgable and dedicated riflesmith, and 3)- the actual specs and/or dies to get this underway ... So the day dreaming is pretty much behind, now it is the "simple" task of real world tasking!
I appreciate the interest and sharing of facts, figures, thoughts and ideas here on the GB forums. Gentlemen, thank you all and to:
Tailgunner 1954,
justC,
tsr 1965,
sand warrior, and as always
nononsense
And as before, I'm open more recommendations, suggestions and ideas if anyone out there has any?
0
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quote:Originally posted by Alan Rushing
First, thanks to everyone that has been providing links, references and other information for the several questions that I have thrown onto the GB Forums: 1) Competition Shooting and Reloading & 2) Ask the Experts.
Second, who can provide me what actual factual information regarding the .338 Norma (Jimmie Sloan) as far as performance parameters and characteristics ... or where might I access such information.
Third, repeat of the above regarding the 308-338 Norma or however or whatever it is being referred to?
It would seem that with them being based upon the .416 Rigby brass, there could be some great performance potential. I am sure that there have to be folks here that are working on these rounds. I'd like to cut through the rumours and BS and find-out what can be found out now, rather than somewhere on down the road, if this is possible!
Appreciate any and all factual information. Thank you, gentlemen.
Huh?
The 308 Norma Mag is a belted case, has a rim of .528 and a base of .508, while the 416 Rigby is a rimless case and has a rim of .584 and a base of .587. The 358 Norma Mag has the same case type, rim and base as the 308 NM.
Now, the 338 Lapua Mag IS based on a shortened 416 Rigby case. The Remington Ultra Mag series is based on the 404 Jeffrey case. The 376 Steyr is based on the 50 BMG case.
Edit to add: There is also the 338 Xtreme which is based on the 505 Gibbs case
50 BMG, 458 Barrett, 376 Steyr
Edit 2: You caught me Alan, I was thinking of the wrong cartridge (corrected above). It didn't help that I had it listed in the wrong category either (I had the 358 NM in US instead of European).
I'll be at the one of the worlds largest cartridge shows next week, I'll have to see if I can pick up a sample of the 338 Norma Mag there. Thanks for the heads up.
Edit 3, for a typo0 -
Tailgunner1954,
.338 Norma Magnum
.338 Norma Magnum load is capable of sending a 300-grain Sierra MatchKing bullet at a velocity 2725 fps. The .338 Norma Magnum provides essentially the same ballistics as the .338 Lapua, but in a shorter, more efficient case. The .338 Norma Magnum design avoids seating the projectile down into the powder space, which aids accuracy and efficiency.
Rifles chambered for the .338 Lapua are easily converted to .338 Norma Magnum simply by changing barrels, as the overall length and a head diameter is the same. Long range shooters who apply their skill at ranges of 1500 yards are finding that this cartridge is one of the very best ways to hit those distant targets.
.338 Lapua Magnum_.338 Norma Magnum
The .338 Norma Magnum is derived from the .416 Rigby case as stated. It has a case length of 2.500" and a loaded length of 3.600" which allows for the new 300 grain .338 VLD bullets to be seated out, creating more interior case volume for powder. With a capacity of approximately 107 gr., the Norma Magnum can match the velocities achieve by the .338 Lapua Magnum.
I and several others have been shooting this cartridge for the better part of a year, so I know it can shoot accurately and the velocity claims are viable. The rifles are custom because none of the commercial manufacturers want to compete against the .338 Lapua Magnum.
Best.
ADDED:
The reference to 'only custom rifles' being available is with regard to the .338 Norma Magnum cartridge not others. And there may be exceptions to this statement shortly...
As I have stated before, the .338 RUM is the performance equivalent of the .338 Lapua in every way necessary to comparison. The two major differences are name recognition and brass quality.
The Remington brass is a slightly lesser quality than the Lapua product in very specific respects. This difference is minor when we consider the average user/life for the cases here in America. These cartridges just don't get fired that frequently by the great majority of owners so the number of reloads per case is insignificant. The lack is offset by the cost per case quite obviously. This too can be obviated when we consider batch sorting the Remington cases to separate out the most consistent and then treating them to the various accurizing steps that precision shooters use.
We can also pay much closer attention to the reamer used to cut the chamber if the option for getting a custom rifle is considered. By using a reamer which is ground to cut a more exact chamber, the shooting results and the brass life get better. Unfortunately, this is not an option when buying from the off-the-shelf manufacturers.
Name recognition or brand sensitivity may seem like a stretch but if you read a lot of the internet traffic along with what the gunwriters and media have to say and write, you will find that the average folks wanting to buy a cartridge in this range will feel that the Lapua is better and more reliable simply because of the pushing, advertising and notoriety (press) that the Lapua has achieved. Facts very rarely enter into the decision since it becomes something operating on the emotional level. This is something a manufacturer dreams of having for every product, name recognition. The public believes, without a doubt, that the Lapua is the better cartridge and they will be buying a sub-standard, sub-performance cartridge with any other choice. Some of this is attributable to peer pressure and other related but subconscious pressures. The wannabes have to have the Lapua simply because it is the cartridge of choice right now by several militaries around the world.
Do not misconstrue this little diatribe as my being anti-Lapua. I am NOT. However, I do recognize other factors that are at work in the area.
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quote:I and several others have been shooting this cartridge for the better part of a year, so I know it can shoot accurately and the velocity claims are viable. The rifles are custom because none of the commercial manufacturers want to compete against the .338 Lapua Magnum.
There is only one who is brazen enough to do this...Remington with the 338 RUM.
Nononsense,
How close is the RUM in comparison to the Lapua?
Best
EDIT 1
Nononsense,
One thing that you mentioned is the brass quality. I know Nosler does not make 338 RUM brass, but it should be a simple necking up processn of the 300 RUM. I have purchased Nosler brass in 243, 260, and 300 RUM, and from what I have seen, it is very good. Also, it is not quite as expensive as the Norma or Lapua brass.0 -
tsr1965,
"...but it should be a simple necking up processn of the 300 RUM."
.300 RUM = 2.850" case length
.338 RUM = 2.760" case length
Yes, it can be necked up but the shoulder has to be pushed back also followed by full-length resizing.
Nosler brass quality seems to be O.K. based on what I've tested and sectioned. I have not made the effort to create the .338 RUM cases from the Nosler brass because I've gotten some satisfaction from cutting proper chambers and sorting brass from Remington.
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Alan Rushing,
I have always found the engineers and technical staff at Norma and Lapua to be most helpful when they can be. Sometimes business and a necessary lack of details go hand-in-hand. Considering the details you want, they should have no problems relating that data to you. Then you will have it straight from the horses mouth, as is said. The cases and ammunition have been available here is the States so the reamers are ready as are the components if they aren't sold out.
Black Hills Ammunition was named the distributor if that hasn't been modified. The initial shipment was sold out in minutes (exaggeration [:D]) and I haven't checked back for more details as I have what I need for right now.
With regard to some of the other questions concerning the .338 Norma:
Norma is making this effort and spending a considerable amount of money in development, testing, manufacturing, distribution and advertising due to the fact that they are interested in becoming another small piece of the huge military pie. The ancillary market is the U.S. 'tactical/sniper/competition' folks who will embrace anything that smacks of the military, immediately and with gusto!
The logic of the case design is similar to that of the .375 Ruger and the myriad of 6mm/6.5mm cartridges available today. A slightly shorter cartridge case but with slightly 'improved' dimensions, loaded to a standard magazine OAL, allows for the same case capacity as the standard cartridges but without having to seat the bullet into the powder space or farther below the shoulder/body intersection.
There is also a new generation of powder formulas which feature better efficiency without sacrificing velocity or exceeding the pressure standards. Those that believe that cartridge and ballistic development ended with the .30-06 Springfield are in for a big surprise. [:D]
Anyway, I'm out of time for right now. Use my e-mail if you want to discuss more of this or anything else.
Best.0 -
I'm going to be swimming against the tide for a while, at least, here. I have studied all I can find on the .338 Lapua and the .338 RUM and the .338-378 Whby and can't see a great deal of difference between all of them for velocity with a given projectile, I'm focused on the 250 SMK, for now. Based on these observations I have built a rifle on a Howa receiver with a 26" Douglas XX in a B&C aluminum bed stock and had the chamber cut for a straight SAAMI spec .340 Whby. Given the .371 freebore there is still almost a full caliber of bullet bearing surface in the chamber when there is a full caliber of the bearing surface in the lands. Now all I can do is try to find the "magic" load and go from there. Any thoughts, guidance or advice would be welcome.
B
Nononsense, thank you for the information. I have been focusing on the 7828ssc as my baseline powder. When I first went into this I tried to use the .300 Whby with the long heavy bullets and Reloader 33. I was loading them .005 short of the leades and loading single shot, obviously. The accuracy was decent out to 600 yards (the max at our range), but I thought I could do better and I really wanted to try to stick with an American cartridge. Remington doesn't have that great a track record of introducing a new cartridge and keeping it going, i.e. 8mm Rem Mag or the .338 RUM, so I went to the Whbys even if the belt uses up room in the chamber that could be powder capacity. Back in the late 50's when I first tried the .300 Whby our only load was a standard large rifle primer 3 grains of Bullseye held in place with a small square of tissue paper and a case full of Hodgdon salvaged 50MG powder and a 180 Sierra spire point. Kicked like hell and would hit something occassionally. Gave that up for the .300 WinMag for my entire police career and am now trying to go back and see what the newer powders and technology will do.
Thanks for your help and suggestions.
B0 -
Full case or perhaps slightly compressed powder charge is my favorite. I'm sure you will be using something slow. I really liked H870. I shot a lot of 50 BMG powder I pulled from ammo. A duplex load will help it burn cleaner. Try shooting over fresh new snow to see the difference. I like ball powder, I think it burns cooler so a normal throat might last a little longer.
I was at the local Cabela's the other day. They had powder, primers and bullets. No Federal 215's, Unique, Bullseye, W231, but they had lots of rifle power. Didn't notice any holes in factory ammo. they had some new brass.
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62fuelie,
I guess since I've been committed to this thread for over 6 years I may as well add a little more to it.
quote: I have studied all I can find on the .338 Lapua and the .338 RUM and the .338-378 Whby and can't see a great deal of difference between all of them for velocity with a given projectile,...
I am suggesting here that no matter what you have studied, you haven't stumbled onto the real reason you don't find any discernible differences between the cartridges named.
The limiting factor to increasing the velocity of cartridges with large capacities is barrel length. Major manufacturers limit most rifles to 26" barrels as a standard. However, once you hit that magical capacity of 85 grains or more, you simply need longer barrels in order to utilize all that powder. This statement in and of itself can be fallacious as well by stepping your powder selection down to the slightly faster selections.
In essence, your .340 Weatherby and the 26" barrel it comes with can be loaded with 4350 powders and then the next level up (slightly slower) as long as you select the Short Cut versions. If you check the Hodgdon reloading website you will find the 2 powders suggested as being H-4350 and H-4381sc. Moving into IMR powders, by my calculations, the highest velocity is yielded by IMR-7828ssc. This same consensus can be applied to case capacity by caliber. Same case capacity with larger caliber diameter necks can use slightly faster powders while necking that same case down usually requires slower powders. This is a general guideline since I'm sure someone will find the one exception...
My suggestion is to try the H-4831ssc since you will find a load with a full case and the best average velocity. But if you're up for some experimenting, H100V Hybrid will accomplish good velocity at approximately 100 fps slower but with the much colder powder thereby preserving your throat for some time at least. This same relationship can be applied to using VVN-560 double base powder as opposed to using VVN-165 which is a colder powder yielding about 100 fps slower velocity.
As an aside, here is the official list of what Weatherby refers to as 'freebore' lengths but then calls it the throat.
This in and of itself is a contradiction of terms which Weatherby has never fully resolved. But for the sake of attempting to explain once again the difference between the two terms, I offer this as the technical definition:
The term 'freebore' is often used in place of the proper term 'leade' because 'freebore' offers a more immediate understanding of the concept. However, the confusion enters as to where this 'freebore' is located. 'Freebore' is the cylindrical area directly in front of the chamber neck. It is separated from the neck by a small 45 degree angle aptly named the transition angle which is what it is. It is the transition between the chamber neck diameter and the leade diameter which is usually 0.0005" larger in diameter than the bullet diameter.
The reason this area is referred to as 'freebore' is because the bullet doesn't contact the side of this chamber feature at all.
The area in front of the leade is named the 'throat' and is a funnel shaped feature which allow the bullet to transition into the lands gently rather than at an abrupt 90 degree angle. Not only does this funnel feature have an angle assigned to it but it has length also. The length is determined by the freebore diameter (largest diameter of the funnel) or the area which contains no lands, up to the smallest diameter which is the bore diameter of top of the lands. This is where the bullet begins to be fully engraved by the lands. This length, while fixed physically, can provide a variety of OAL answers because of the the various angles of the bullet nose. Round nose bullets will have a shorter OAL in the same case when compared to the new Hybrid bullets which can be seated further out of the neck.
H-870 and 50 BMG are far too slow for this cartridge and bullet selection as I stated above. Ball powders have their place when using mechanical powder dispensers and in a limited number of cartridges/bullet combinations. The ball shape allows the granules to be consumed at a faster rate when compared to stick powders. However, in order to control (and vary) their burn rate the outside of the balls are coated with deterrents and graphite which are both major contributors to fouling in your barrel.
Best.0 -
nononsense,
Tons of good information here, as usual. It's interesting as you guys are discussing the .30 and .338 calibers when smaller calibers are found to be more efficient. Efficient yes, but too small in overall ability to launch a heavy enough projectile the distances we are now attempting to attain.
We can massage a case to the ultimate to make it more efficient, but at some point we bring it to the point it is detrimental to the process. Meaning if we sharpen the shoulder too much we increase the burn too quickly and make slow powders burn to fast to use their full potential. Not to mention detrimental to the life of the barrel. Pressure built too quickly causes too much heat. And, no matter how much "Freebore" (please delve more fully into this subject as nononsense said, he is a great resource on this) is included in the barrel it is still going to increase wear. Exponentially, I might add.
While some at a very highly competitive level can do this most of us don't. Wearing barrels too fast weighs against accuracy not only physically on the barrel, it also weighs against the shooter who doest compete at that level mentally as he begins to lose faith in his rifle. If one can't pinpoint his shots, they usually stop trying. Using the most accurate and efficient cartridge one can without ramping it up to the point it wears on barrels too fast is the better way to keep a rifle in fine tune along with the shooters mind. A mid-range shooter can then trust the rifle enough to keep improving themselves.0 -
sandwarrior,
Thank you for your kind comments.
quote: It's interesting as you guys are discussing the .30 and .338 calibers when smaller calibers are found to be more efficient.
Absolutely correct. But as we've seen with the greatest example, the 6PPC, there is little left to do except continue to shoot the same cartridge with the same bullets and accomplish the same group sizes. Virtually every point blank benchrest shooter fires this cartridge and achieves similar results.
Someone once wrote that the 6mm PPC was the winningest cartridge in the world, ever. It had won the most competitions and set the most records of any other single cartridge.
To this statement I took a subtle umbrage in that since everyone was shooting the same cartridge and had been for the last 41 years there was no competition. Therefore since every competitor was shooting the same cartridge, every record shot simply added to the total number of records without any competition.
But this does not take away from the fact that the PPC is a very efficient case which is by design, thank you Ferris Pindell and Louis Palmisano. Their dedication to design and development has led to an explosion of newer case designs and derivatives which continues on to this day. So many of the newer designs depend on the concept of 'short and fat' even if the case is apparently 2.5" long as in the .338 Norma Magnum. When compared to the highly vaunted .338 Lapua, it is certainly a 'shorter, fatter' case. But it is also tested and proven to be more efficient than the Lapua and even to a small extent, the .338 RUM.
The next wunderkind, albeit slightly larger than the PPC is the 6mm Dasher. This case has taken the middle distance and long range shooting disciplines by storm. It has also broken some of the taboos relating to shoulder angles and neck length. The Dasher case, based an the 7mm BR case which Remington developed, uses a 40 degree shoulder (like what is commonly referred to as Ackley Improved) instead of the common 30 degree shoulder. It also features a much shorter neck. The body was moved forward 0.100" which left the neck distinctly shorter than is commonly accepted.
As with all things in the shooting public, this case was not to be left alone in all its glory. Norma in conjunction with the marketing arm of Shiraz Balolia (President of Grizzly Industrial) has brought forth the newest iteration of the Dasher in a commercial form featuring a longer neck by setting the overall case length to 1.600" instead of the 1.550" of the 6mm BR and the original Dasher. Now, instead of a multi-step case manipulation including but not limited to, fireforming, we can simply call Grizzly, Inc. or Bullets.com to order factory fresh Norma Dasher brass fully formed and ready to load and shoot. This also provides a stimulus to the reamer makers and to gunsmiths who will require the new reamers in order to satisfy the public demand for the newest of the new. My guess is that what was a probable 70% dominance of the 600 yard and 1,000 yard prone and benchrest competitions will now blossom into total dominance just like the 6PPC. But that's where it will all end because the smaller cartridges just can't keep up when the wind comes up or the distances increase beyond 1,000 yards.
quote:Efficient yes, but too small in overall ability to launch a heavy enough projectile the distances we are now attempting to attain.
Now begins the rise of HORSEPOWER! But it's horsepower with an emphasis on efficiency. We are not seeing the extension of the 30-378 Weatherby or the .338-378 Weatherby by any means. We're jumping past those cases and running headlong into the .408 CHEY-TAC case necked down to accept .338 and of all things, .375 bullets. Now we're talking about prone competitions from 1,200 yards to (are you ready?), TWO MILES or 3,520 yards. This is hyped as the 'King of the Two Miles' which has just concluded at the Whittington facility near Raton, NM. Three men managed to hit the gong at the 2-mile setting, 2 using the .375 Chey-Tac Improved and the other using the .338 Edge or .338-300 RUM Improved.
But the other development which must go hand-in-hand with the case design is bullet design. The winning bullet used in the above was a proprietary R&D bullet from Berger which has not been released to the public yet and according to the press release, may not be made available to us peons. However, the .338 bullets are commercially available from Cutting Edge who also happens to make a couple of pretty good .375 competition bullets as well. These are the ones I shoot since I'm not a member of the inner circle at Berger.
We are expanding out horizons as never before, both at the small end and the big end. The next big push will necessarily have to be in glass. Even though the glass industry has made great strides, we are still handicapped by environmental conditions which degrade our visual acuity. Now if we could just find a way to vacuum out all the dust particles and then remove all the moisture particles, we might be able to go a little further...[;)]
Best.0
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