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rsterne
I have just placed an order with Mike Sayers at TJ’s for him to make a custom mandrel to produce 7″ twist barrels for my new 100 gr. & 113 gr. BBT’s in .257 cal…. The 113 gr. is basically a scaled down version of the .308 “Whiteout” bullet that won the EBR…. It won’t require Helium to achieve the power necessary to drive it into the mid 900s, however…. Something between 3600-4000 psi air with a 30-32″ barrel should do the job…. I’ll let you know when the mandrel is done and barrels can be ordered…. Below are what the bullets look like….
http://noebulletmolds.com/photos/albums/257-100-FN-BT-/257-100-FN_-BT-_102_gr_Sketch.Jpg%5B/img%5D
http://noebulletmolds.com/photos/albums/257-113-FN-BT-/257-113-FN_-BT-_113_gr_Sketch.Jpg%5B/img%5D
Bob
rsterne
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shaunsharpton
I would suggest you ask W.A.R….. My guess is that they can make it fit your Flex…. but whether or not you can get the FPE necessary to take advantage of it would be the question…. Longer barrels and more pressure are the main route to high FPE…. At 950 fps, the FPE is twice the bullet weight, so a 100 gr. bullet would require 200 FPE to drive it at that velocity…. I think the Flex is more in the 100 FPE range in .30 cal, probably less in .257…. W.A.R. are the manufacturer, they would know the guns capabilities better than anyone….
Bob
No PCP will develop the same FPE when you reduce the bore size, you lose area for the air pressure to push against…. Dropping from .30 cal to .25 cal, a 30% loss in FPE would be expected at the same pressure and barrel length, on a full-out performance basis…. Of course if the larger caliber is suffering from small ports, etc., the loss could be less…. I would expect the Flex in .257 cal would be a 100 FPE gun at best…. meaning 50-65 gr. bullets, which will work just fine in a 14″ twist….
The Slayer, with a long barrel, might be a good platform for pushing 200+ FPE in .257 cal…. or one of Brent’s Extremes…. The late Jack Haley showed us that 300 FPE was possible (for 1 shot) in quarter-bore, with enough pressure and barrel length….
Bob
Yes, I want the barrel, but I’m definitely going to be aiming for something like the SLAYER, perhaps the rifle version instead of the Bullpup. Although some 28″ barrel bull pup guns look much shorter. The flex should do well with the 67 grain .300 you designed since it’s using the 2014 EBR Winning TJs 26″ twist barrel, 17″ long.
Rizen 1
shaunsharpton
teemu
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