#1
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Max Pressure for .17 Rem Fireball ?
For the .17 Rem Fireball, Quickload gives Pmax (MAP) as 58,740 psi, whereas the Chuckhawks site indicates that the SAAMI maximum average pressure (MAP) is 55,000 psi.
Anyone know, for sure, which is right ? http://www.chuckhawks.com/17Fireball.htm |
#2
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I DO NOT KNOW... however, since most guys don't mind chambering it on a Contender so i'm guess i'd lean more to the 55k max...
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#3
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Here is some more info that will confuse you, consider the following pressures of these factory cases: (Per QL info)
221 Rem F B CIP PSI max = 46412 222 Rem CIP PSI max = 53664 222 Rem Mag CIP PSI max = 58740 223 Rem CIP PSI max = 62366 223 SAMMI Piezo max = 55000 5.56 Nato max = 58740 All these cases have the same head size within a couple of thousands of a inch. As we all know, the first thing that shows any signs of trouble is the primer pocket area, ie leaks, expanding primer pockets, blown primer pockets etc. Without sectioning all the above FACTORY case heads to see if there is any great DIFFERENCE in construction of cases, and not known the tempering spec's of EACH CASE, why is there such a BIG DIfference in pressure rating??? Other than POWDER load amounts/data set by the factory spec's etc. Why not take 223 Rem factory cases, form them into 221 cases and shoot safe loads to 62366 PSI, there by making BETTER LOADS ?????? regardless the pressure of the ORGINIAL FACTORY LOADS loaded at 46412 PSI. The differance between these 2 pressures (+ or -) is equal too about 203 FPS in that load, all things being equal, the difference is quite a bit when thumping varmints! More to ponder about.............. Don
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"ANY person that fears me owning a firearm, then I have reason to not trust that PERSON" ------------------------------------ "We must reject the idea that every time a law's broken, society is guilty rather than the lawbreaker. It is time to restore the American precept that each individual is accountable for their actions." Ronald Reagan |
#4
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I think the pressure specifications on the ammo are set mainly for the gun makers to design their actions to proper strength levels. What the case will withstand has mostly nothing to do with it. I would venture to say that a lot of hand loads that are used are far above the SAAMI pressure specs if there are any for the round. Larry
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A gun is just like a parachute, if you really need one, nothing else will do. |
#5
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Quote:
If the published data only goes up to 55,000, the SAAMI max, then all you know is that you have exceeded 55,000 but not by how much. And that is only in the .223 Remington. Even if published data exists that is tested to 62366 PSI, you are still flying blind after forming the case down to .17 Fireball. All you can know is you have exceeded max, not by how much. Western Powders does publish high-pressure data for some 20-caliber wildcats. When I first noticed the pressure, I sent an email inquiry and got a response from their chief ballistics guy: http://www.saubier.com/forum/showthread.php?t=1928 |
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