P.O.Ackley tested a number of military bolt actions to destruction. Does anyone know where to find the results, and specifically how the Krag really did?
Grouch
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P.O.Ackley tested a number of military bolt actions to destruction. Does anyone know where to find the results, and specifically how the Krag really did?
Grouch
His handbooks have been re-printed, and are available. Try the book dealers on the internet.
He did not find the Krag as strong as the later actions, but his comment was that it was quite strong. Note that his method was to load hotter and hotter loads, and some of the failure modes do not respond to this.
With a Krag you run the same risk as with a low number 03, the heat treatment left the metal brittle, but not to the extent of the 03s which were overheated during the forging process.
How safe are old Krags to shoot with factory loads? I love shooting mine, but wondered just how safe they are.Any opinions would be appreciated. Thanks, Paul.
your Krag should be perfectly safe with factory loads assuming your rifle is in good condition. U.S. factory loads are made up with any strength issues of the rifle they're going to be fired in in mind.
Warning: I can not verify this post, as Fred Telke has been dead for ~30 years. It is true to the best of my knowledge.
My father-in-law shot a Krag competitively during the '20's to 30's. He experienced a cracked bolt lug. As a tool maker he had access to all the tools, and heat treating equipment needed. He had taken some college level metallurgy classes so he took the bolt to the prof. The professor concluded that the bolt was indeed brittle, but that one made of a different alloy, and heat treated properly would be much stronger. Fred made one and used it in competition for many years.
Unfortunately, after he married in 1939 the rifle was sold as he stopped service rifle competition.
Some Krags, like the later Springfields, were overcooked and made brittle, I have on in the 13000 serial range that is cracked in two places, one right behind the locking lug recess, the other further back in the bottom of the receiver. This receiver is very hard, won't take a file, and has a distinctive high pitched ring to it when struck. Since the case is fully inside the barrel ring, the Krags don't fail like the later Springfields though. In fact I had shot the cracked one a few times before noticing the cracks and retiring it.
The Krags did potentially have the same metallurgical problems as the "low number" M1903s, but they also had a serious design flaw. Both the earlier Danish Krag and the later Norwegian Krag were set up so the guide rib acted as a second locking lug. So, even though the lugs were not symetrical, those rifles had two substantial lugs and both are quite strong.*
But when the U.S. adopted the Krag, they (not Krag) decided to set it up so there was only one true locking lug and the guide would act as a safety lug. The safety lug would not bear and would touch the receiver if, and only if, the front lug failed. I have never been able to learn why that decision was made, but it severely reduced the strength of the action and put all the strain on one relatively small lug.
Krag locking lugs broke frequently throughout its service life.# At one point, the Army tried to increase bullet velocity to 2200 fps, and even issued sights graduated for that velocity. But so many bolts broke with the new round that it was hastily withdrawn from service and the sights replaced with the old ones.
*A company called Mauser had a patent on dual front locking lugs as part of the bolt body, which is why Krag couldn't go that route.
#Which is why there was a good supply of new Krag bolts up to recent times.
Jim
The Norwegian and Danish krags supposedly used the bolt rib as a second locking lug. I've never shot one, but I've seen a few. Jim Bedaux in Albuquerque had a real nice one in 6.5x55, sporterized with a Bedeaux custom stock. The Danish Krags were chambered for a really hot 8mm rimmed cartridge, definitely a step up from the .30 Army.
As for the US Krags, they will take a fairly strong load without coming apart and IMHO make a way better big game rifle than a .30-30.
jn
I don't know about a "way better"; the .30-40 case will hold more powder, but factory loads are not impressive and the factor we are discussing limits the .30-40 to pressures in the 40-45k cup range. If I were limited to loads in that general range, I would probably choose based on which type of rifle I preferred rather than the cartridges.
One interesting thing, and I will gladly stand corrected if I am wrong, but I don't believe any commercial rifle was produced in .30-40 except the Winchester 1895. Most other military calibers have automatically created a large sporting rifle following (think .45-70, .30-'06, .308, and .223), but I can't recall any other commercial sporter (not a custom rifle) regularly chambered for the .30-40.
Jim
Blake
Remington-Lee
Remington Rolling-block
Winchester Single-shot (?)
Para,
don't forget the Ruger #1, and both the original and the new Winchester Hi-walls. What else? The gatling gun.
The green box 30-40 loads throw a 180 gr. round nose at 2400+ fps. I call that way better than the .30-30. I like Sierra 220 RN for elk in the woods. I switched to the Krag from my 8x57, primarily because I like the rifle better. Long as I'm hunting in timber I'll stick with the iron-sighted Krag, cause it is so much easier to lug over deadfalls and through heavy brush.
The biggest problem with the Krag is it's probably too much gun for deer. Maybe with 150 gr. bullets loaded for "conditions" it would be OK ... others may disagree.
jn
No (?) about the Winchester Single Shot. It was offered in .30 Army (which we call 30-40 Krag today); No. 3 receiver (that's the "high wall"); standard barrel was 30" round No. 3 weight; shotgun buttplate.
More recently, the Ruger No. 3 Single Shot. I have two. :)
Resp'y,
Bob S.
Remington #5 rolling blocks too, rifle and carbine, very few of both.
In regards to the single locking lug...I have read where people stoned the front lug until the safety lug also became a true locking lug. The claim was that the two bearing surfaces made the action substanially stronger. I'm not recommending to do it. Nor have I attempted such.
I just got a bolt from a fellow who did this, headspace would be excessive, not a big deal if you plan for it on the first firing, either by greasing the cases or seating a bullet long and hard into the rifling. One could also make his Krag ammo for this setup from .405 Winchester brass, which has a thicker rim. The fellow opted to replace his bolt body with a new one. Luckily the majority of the metal removed via the use of valve grinding compound came off the locking lug and not the locking lug recess in the receiver. On the other hand I have a 92/96 that someone set up with the safety lug touching, it does not have excess headspace. The bolt body is an original 92 item with the uncut safety lug, some armorer's work I would guess. I've also read about someone removing too much locking lug, so that the safety lug took all the pressure, and the receiver cracked where the safety lug made contact.
That safety lug usually has enough clearance that IMHO removing metal from the front lug to make it bear would not be a good idea unless one set the barrel back also to prevent excess headspace.
Comments on the Ruger (No. 3, but I don't think the Ruger #1 was made in .30-40 as a standard caliber) and Winchesters are appreciated. Remington RBs in.30-40 are so scarce I will cop out on that one as not being a standard caliber. As to the Gatling gun, I did say commercial sporter and I don't think the Gatling quite fits.
Still, it seems a very small commercial use of a cartridge that was U.S. standard for some 11 years, and is not at all a bad round.
Jim
Jim,
I agree w/you on the whole lug-lapping thing. If you want both lugs bearing, get a Norwegian or Danish Krag.
I do think that if the US had stuck with the 30-40 the way the Brits stuck with the .303, you would have seen lots more rifles chambered. Well, the Winchester model 54 wouldn't look like a springfield - it might have been been a Krag-based design? An Remington might have refined the Lee. Savage would have figured a way to use the 30-40 in their 99. Maybe a shortened 30-40 with the shoulders blown out.
\
the P14/P17, instead of the Lee, might have been the take-off for a series of sporters from Remington. What else? H&R would have made a break-open 30-40.
You got to remember that it wasn't until after WWII that the '06 became king of the hill in sporter-land. During the depression no one could afford a sporting rifle, and the 30-40 was kind of the default big game rifle in the north woods (to some extent), and especially the west and Alaska.
As to the rest of your post: What??!! The gatling isn't a sporting rifle?
jn
Hi Jon, scarce indeed, one of the RB 30/40 carbines came up on gunbroker not long ago, seller was from here in Indiana, had no idea what he had. Guys on the Remington Collectors forum denied their existence. It was rusty, had parts missing, sold for over $600, which I'm sure surprised the bejeebers out of him. So you're into custom bikes, someday I'll post a pic of my customized 1970's vintage Schwinn road bike.
The .30-40 saw a lot of sporting use in the 1920's and 1930's only because the Army was selling off the rifles for as little as $1.50, dirt cheap even for that time (equivalent to $50-60 today). This was at about the same time experimenters began to develop "wildcat" cartridges, and the .30-40 became the basis for at least half a dozen variations. In many cases the old Krag was rebarrelled, other folks worked over rolling blocks, Winchester and Stevens single shots, and other rifles to take those cartridges. While many of the .30-40 based wildcats filled a gap and were moderately popular, most enjoyed a brief writeup in one of the gun or sporting magazines and quietly went wherever old wildcats go.
Jim
Jim,
The Krag saw a lot of families through the depression in the west .. putting deer and elk meat on the table. When I was a teenager, just starting to hunt, I used to listen to the stories the old guys told. Some of them were still using the same rifles .. one guy had an '86 winchester 45-70, another had a beautiful Savage 99 with a tapered octagon barrel, in 38/55. Then there was the Krag. Almost all of those guys had a Krag story to tell.
PO Ackley was wildcating the Krag all over the place, is why he was interested in the strength of the Krag action. There were so many of them around.
After the war the country entered a period of great prosperity. Wages in the woods went way up, a sawyer or log truck driver could make the equivalent of $90-100,000 a year. Winchester sold a **lot**of model 70s in the west. Add to that the DCM 03-A3s you could get for $12.50, and all the surplus Mausers flooding in. Good times turned the Krags into backup guns.
well, that's one POV on the matter,anyway.
jn
To get back to the original question, P.O. Ackley's tests are reported in his Handbook for Shooters and Reloaders, Vol. 1. I don't know if it is still in print, but used copies are around. The trouble is that the results are about worthless. He proved that rifles will blow up, something most of us already know and that people knew then. He had no pressure taking equipment, so comparisons are not possible.
He did not use any discernable methodology, simply setting out to find a load that would blow a rifle. The results are interesting in showing HOW rifles fail, but of little value in showing at what point they fail. He might blow up one gun with A grains of B powder and another with C grains of D powder, proving nothing except that those particular loads would blow that rifle. He even used heavy charges of 2400, which would probably blow any rifle ever made except possibly a Remington 700, and likely would harm it.
I don't doubt Ackley's basic findings, but I wish he had been more scientific about obtaining the results. He did debunk some myths, especially the one common at the time that the Japanese Arisaka was total junk, made of cheap tin or scrap iron, and that the 98 Mauser was a superstrong product of German engineering and would never fail. Both views were nonsense, and Ackley proved it.
Jim
Jim,
Excellent post. It's obvious that you have a sense for scientific method, something that kids don't get taught much in school, and that a lot of people are openly hostile to, especially when they disagree with its results.
Keep it up!
jn
No "?" on the Model 1885 Winchester Single shot in .30-40; Col. Whelen wrote about his, and I've seen a picture of it. There were a few Remington-Hepburns, too.
This is an interesting tid-bit you've posted. Understanding the botched metallurgy of many if not all of the US Krag actions to some degree, coupled with the brittle bolt's single forward locking lug, backed up only by a non-bearing bolt-rib safety lug, it's obvious the reason for limiting these rifles to mid pressures at most.Quote:
Originally Posted by us019255
By contrast there is the Norwegian Krag, which to my understanding was produced with correct metallurgy and processes, then it was case hardened. Work was applied to the bolt as well making the bolt-rib a true second locking lug, bearing against the action's rear ring through careful fitting at the factory. Though not as strong as most dual forward lug actions, the "Norge" Krag is quite a bit stronger than the US Krag...
If manufactured today with modern alloys, with both lugs working to lock the action, how strong would this smoothest of bolt actions become... any thoughts?
"Contrary to some rumors, the Krag-Jørgensen action can be modified to fire modern, high power cartridges. During World War II, and also in the early 1950s, several were produced in 7.92 x 57 mm, which can hardly be considered a low power cartridge. A number of Krag-Jørgensens have also been converted to .30-06 and 7.62 mm NATO for target shooting and hunting. However, it must be stressed that these were all late-production Norwegian Krag-Jørgensen rifles, made in an era when metallurgy was vastly more advanced than when the American Krag-Jørgensen rifles were made. The American Krag-Jørgensen also has only a single locking lug, whereas the Norwegian and Danish versions effectively had two lugs." Krag-Jørgensen - Wikipedia, the free encyclopedia
The CIP MAP for the 6.5 × 55 is 380 MPa (55000 PSI). SAAMI MAP for this cartridge is 46,000 CUP or 51000 PSI.[2] All Swedish Mauser actions were proof-tested with a single 6.5 × 55mm proof load developing approximately 55,000 CUP (66,000 psi).[3]
-- P.O. Ackley. In his words "It gave no trouble even with powders as hot as #4198 in quantities sufficent to require compression to get in the case. Such loads blew the primers but did not hurt the action." He ended up with a case full of 2400 before the action ruptured and even then it wouldn't have done serious injury to the shooter. He tested four actions, two standard and two that had been re-heat treated. All similar results.
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And Ackley would have blown up Remington 700s as well!
In a recent trade with a friend in exchange for some shotgun parts, I inherited a complete barreled action, a 6.5x55mm Norwegian Krag with a poorly done flat-gate magazine conversion... Otherwise, the action and bolt are tight and serviceable. The painted barrel and it's bore are in excellent shape. It looks like one of the sporterized models since it is fitted a leaf-spring elevator ramp and buckhorn sight on the rear and a ramped leaf on the front. Centered at the top of the 23" barrel, just ahead of the receiver ring is stamped "Swedish M-94"... the 4 is stamped sideways like a "lazy-4".
A hobbled up stock from another rifle came with it... I checked it out thoroughly then picked up a box of PPU 139 grain 6.5x55 ammo, my chronograph, and headed for the range.
Once there, I opened bubba's flat-gate and rolled 3 rounds into the magazine, closed the flimsy hatch and fed the first round into the chamber. I aligned the sights on the target and squeezed it off. The recoil caused the loading gate to fly wide open... it opens forward like a Danish Krag, with a simple hinge and a poorly engineered snap lock. I taped the damn thing shut and fired the rest in single shot mode.
The rifle handled the factory ammo just fine, no signs of pressure, no primer flattening or primer movement at all, and the cases showed good chamber contact all round... it is obvious it will handle much more. The average velocity was 2381fps with a high of 2411 and a low of 2347. Seems about right for factory stuff thru the short barrel on this Krag.
Now, to fix the badly bubba-ed loading gate and what is left of the carrier assembly... this will take a little time to work out since the magazine box's lower gusseting has been completely hacked off.
I believe that US Krags were set up with only the locking lug bearing in order to simplify manufacture and improve interchangeability. Springfield was anal about interchangeability. That they weakened the action probably didn't occur to them. The rifle met their requirements in 1892 and perhaps they couldn't envision needing a rifle that could handle more than 45 KSI. Keep in mind that a 220 gr bullet at 2000 fps was really smoking in 1892!
The Krag actually has two safety lugs - the guide rib and the bolt handle fitting into the receiver mortise.
There is a gentleman that posted the story over on KCA of milling off the locking lug and then testing the Krag with full power loads without the locking lug with no I'll effects. I forget the charge he had to use to finally cause failure but it was well above any normal pressure a Krag should ever see! Oh, and the bolt held even in failure. The receiver ring failed as it did in Ackley's testing.
Ruger in #1 and some Husqvarnas were commercially produced in 30/40 Krag for sport hunting as well.....probably others on a short term production runs that died out as "superior" rounds and rifles were produced