This a paragraph out of an article published recently in the African Sporting Journal. Have any members of this forum had a rifle action freeze up in hot weather as was described here?
".416 Remington Magnum.
This is an increasingly popular, affordable and �available� cartridge - factors which make it appealing to many African PH�s. Ballistically this cartridge is identical to the .416 Rigby. I therefore has it all ballistically - save for some really unpleasant recoil. Some of the .416 Remington�s I handled are just too light ( like the Sako for example ) and boy do they kick ! Also, the .416 Rem Mag produces too much chamber pressure.
[ Footnote. Each October, at the end of the hunting season, the Zimbabwe Professional Hunters & Guides Association holds a training course for �learner� PH�s and Guides, in the Rifa Safari Area of the Zambezi Valley. October is �Suicide Month� here in Zimbabwe, and it gets mighty hot down in the �valley� at that time. Practical, rapid fire shooting tests, are an important part of the learner�s course and they always prove to be informative in many ways. Under such conditions, I�ve witnessed on more than a few occasions, �frozen-solid� bolts frantically being kicked and hammered open, once with half a brick ! Somewhat alarmingly, the .416 Rem Mag has more often than not, been the culprit. As an instructor on the course, this worries me, especially as some of the rifles chambered for this cartridge have only small, �finger-nail� type extractors. From a PH�s / dangerous game hunting perspective, this is an invitation to a premature obituary notice and why Edd and I attached such importance to chamber pressure in our deliberations."
Thank you for the reply.
Firstly I would like to know exactly what "frozen bolt" was as it can mean different things to different people.
However, if we leave out high energy loadings for the other common magnums with parralel cases, that is, the 7mm Rem and 300 Win, their normal loadings are less that the 416 Rem factory loading as compared to a maximum handload.
From a 24 inch Rem 700 I chonographed Remingtom 416 ammo at an average of 2410 f/s which is not far below the 2500 f/s you can get it up to without too much trouble.
300 Win Winchester 180 grain power points are lucky to hit 2900 f/s from 24 inch barrel but top reloads take them to just under 3100 f/s.
So, my limited testing shows the Remington 416 ammo is closer to the most you can get.
The author mentions finger nail type extractors which suggests the Remington 700 rilfe.
The Rem 700 because of the the very wide locking lugs has poor primary extraction as compared to Model 70 or Mauser 98. But if the bolts were really "frozen up" then the poor primary extraction of the Rem 700 would have had no influence.
However, it is possible that the hotter Remington 416 ammo in conjunction with heated up ammo and the parallel case, could have meant the bolt handle lifts into the fully open position, but due to the poor primary extraction, the shooter would then have to belt the bolt back to break the case free fromthe chamber.
They are my thoughts.
Mike
In any event, I don�t believe that there is anything unique to .416s that would cause extraction problems. I have shot well over 50 boxes of .416 through the years and I have never had any pressure related problems. It would be difficult to draw any conclusions from a few instances of heavy bolt lift.
I agree with Mike, these problems can be contributed more to the gun and its condition than to the cartridge design. Too many people have shot .416s for far too long. If there were extraction problems that were unique to the case design, we would have known about it long ago.
I have always wondered why Africans think they have the hot weather cornered..I was raised near Presidio Texas and it hits 130 degres from time to time and Arizona ain't all that cool...Our guns work there....
This is another old wives tale being propagated by an ill advised PH...shows a little knowledge is a dangerous thing...
Bottom line is that was a cordite problem, and with our new US powders it seldom happens unless overloaded in the first place and believe me I can only think of one cartridge that is overloaded....I don't have any experience with the new rounds like the RUM, STW etc. but I suspect they may be a overload problem to get the claimed velocity.
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Ray Atkinson
If you chonograph 270, 30/06 and 416 Rem ammo you find the 416 is much closer to a top handload and especially compared to 30/06. Whether this is because it is loaded to higher pressure or whether it is because the powders available to the factories are more suitable for the 416 Rem than for the 270 or 30/06, I don't know.
I think Zero Drift probably has something when he mentions the condition of the ammo.
Also, there may be more to it than just temperature. For example, in Australia ammo, the gun, the body of the car and anything else will become far hotter in our inland than it will with the same "air temperature" closer to the coast.
I have heard many people say that Africa's climate is very similar to Australiasand they both are in the Southern Hemisphere.
Remember the Hodgdon Extreme powders are Australian and those powders were not made for marketing reasons as they are based on our military powder for the 7.62 Nato.
Mike
Between 400-grain Barnes "X" bullets, 350-grain Speer Mag-Tip bullets, and 400-grain Hornady RN bullets, I've never had "pressure problems" with my loads and I can assure you I've built up some "warm" loads.
Stop reading magazine articles and go do some shooting.
Russ
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"Out here, 'due process' is a bullet!" -- John Wayne, "The Green Berets"
If I am not mistaken, Man Magnum was stating a case against the 458 not the 416, but I could be mistaken, what issue?? I have most all of them....
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Ray Atkinson
I have never had a bolt stick on a DGR, that extra 100 FPS is unnecessary in a big bore 416 Rem...I can get an easy 2350 to 2400 FPS with a mild load of 79 grs. of RL-15 in my gun and the brass last forever...Same with my 404 Jefferys and 90 grs. of IMR-4831 (95 is max).....
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Ray Atkinson
How soon we forget! Take a look in the 2/01 issue. Page 60 to be exact. In an article by Ganyana.
Telly
Regards,
JohnTheGreek
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