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You can see from above posts I like Enfields and here is picture
of how we set up action for long case and a singlestack magazine. We open bottom of action for length and use a lip type magazine insert to feed cases single stack. And lips are springy so we can load from the top. ![]() Here is the second gun I did years ago in the 585HE, an old style Ruger 77. And at that time I used the cases I made myself and they work great in the gun, high pressure loads, and extracted easy like the new ones from Bertram. ![]() Here is some math to show why I really like really big bores. There is term called Average Barrel Pressure, which is the average of all the pressures in a barrel, from the start where you have highest, called peak pressure. to the lowest at the muzzle when bullet exits. For high powered rifles average barrel pressure run 15-18000 psi. There is a formula that can be used to get Average barrel pressure fairly close if you know the muzzle energy. We multiply ME times 12 and divide by barrel cross section x length. We simplified it to get the 12 figure, It is inverse of the bore dia x 5 For the 585 it comes out about 10 Example a 458Win usually loaded to 5000 ft lbs, say in a 24" bbl. ABP = ( 5000 ft lbs x 12) divided by (.17 sg in x 24") = 15,000 psi Now you see there isn't a lot of room for big gains, as it would take peak pressures damaging to brass and gun, to get say 50% increase. Now example of 585HE in the 26" bbl we like, say a 7,000 ft lb load, a real moderate load in this case. Could use 10 in place of 12, but kept it all simple ABP = (7000 ft lb x 12) divided by (.27 sg in x 26") = 12000 psi The bigger bore allows for a much larger potential, a 50% gain is easy to do.Ed
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Ed Hubel |
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