New FX Slow Twist barrels.

twist rates.1639978820.JPG

 
I suppose that I can add an update to my prior post in this thread regarding the 37" twist Superior .30. I've concluded that this barrel is most accurate around 915FPS with 44.75 JSBs. The minimum speed for this thing to shoot under an inch is 880FPS. Accuracy clearly degrades over 930FPS. The fastest that I have shot these pellets from my 500mm Maverick is somewhere north of 1000FPS.

I have also shot the 50.15 JSBs with this barrel to about 980FPS. They were bucking the wind like slugs at 100y and shooting just as tight as the 44.75 on a calmer day, but then I would get anywhere from 1-3 nasty flyers per 13 shot mag. They suck under ~920- great from 940-960 , but I haven't been able to eliminate the flyers with sorting by head diameter.

In retrospect, I still have the .30 700mm pellet liner with a 44" twist from my MKII Impact, and that barrel is just as accurate with a max velocity of 905FPS with the 44.75gr.
 
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The original liner that came with my wildcat MK2 30 cal is a 1:37 twist and is very accurate. So glad I never swapped it out.
On my MK2 impact 30 I also use a 1:37 twist. It is very accurate but only if I do my part past 50 yards.
Can agree with Bigragu and the rest about the :37. Just a fantastic TW at the speeds @mtnGhost states. Have had MOA results out to 100 when I do my part.

Patrick
 
I had heard that FX was going back to the slower twist rate for .30cal. My FX Maverick's 500mm Superior liner has this 37" twist rate, and it's a frigging laser beam with 44gr JSBs in the high 800's & low 900's (I've admittedly not tested it in the mid to upper 900's, but I have the power on tap and may try this soon with my Mav shooting hot with my hammer weight ).

The 26" twist in the TJs have been more ideal for shooting 44gr in the lower 800's. I haven't shot any of the faster twist Superiors in .30cal much, but I know they're not as well suited for the 44's.
Try the hybrids at 860-870 out of that compact maverick and you'll really see accuracy out of the maverick!
 
I had heard that FX was going back to the slower twist rate for .30cal. My FX Maverick's 500mm Superior liner has this 37" twist rate, and it's a frigging laser beam with 44gr JSBs in the high 800's & low 900's (I've admittedly not tested it in the mid to upper 900's, but I have the power on tap and may try this soon with my Mav shooting hot with my hammer weight ).

The 26" twist in the TJs have been more ideal for shooting 44gr in the lower 800's. I haven't shot any of the faster twist Superiors in .30cal much, but I know they're not as well suited for the 44's.
I have shot the 44's from the :26 and can say they are not as stable and accurate at the standard speeds we are use to seeing. I prefer the :37 overall out to 100.

Patrick
 
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Why continually come out with more barrels and different twist rates? Does FX have a tabulation on the best projectile and velocity for each liner? Or are they just trying to sell us liners so that we can experiment ourselves. R&D should be in their backyard.
They test them well before we (regular folks) ever see them. I have heard it first hand from sources we all know.

Patrick
 
Why continually come out with more barrels and different twist rates? Does FX have a tabulation on the best projectile and velocity for each liner? Or are they just trying to sell us liners so that we can experiment ourselves. R&D should be in their backyard.
Well. The FX appeal to a certain personality who tinker. I believe there are YT videos where some folks from SA who state “slugs loves speed”. They do however forget to tell its in a FX context only. These YT airgun “scientist”(salesmen really) make their statements like its dogmatism. Using LW barrels for instance , slugs is accurate at slow speeds too. So it isn’ speed that determs the stability of the slug alone. Its also a relation with the rifling profile, the land/groove depth and twist. Remember FX is trapped in their production method making barrels. Compressing the rifling from outside sets a barrelwall thickness to a max. If the liner too thick it will become impossible to make it such way. Cutting the rifling by a singlepoint cutting or a buttonmethod the barrelwall thickness isn’t an issue. Slugs(leadbullets) need a deeper “grip” than what FX rifling method is capable to do. Thats why we still see all these different barrels being made. When this said I am an admire of FX. They are innovative like no other. Something other airgunmakes could learn from.
 
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Well. The FX appeal to a certain personality who tinker. I believe there are YT videos where some folks from SA who state “slugs loves speed”. They do however forget to tell its in a FX context only. These YT airgun “scientist”(salesmen really) make their statements its dogmatism. Using LW barrels for instance , slugs is accurate at slow speeds too. So it isn’ speed that determs the stability of the slug alone. Its also a relation with the rifling profile, the land/groove depth and twist. Remember FX is trapped in their production method making barrels. Compressing the rifling from outside sets a barrelwall thickness to a max. If the liner too thick it will be i possible to make in such way. Cutting the rifling by a singlepoint cutting or a buttonmethod the barrelwall thickness isn’t an issue. Slugs(leadbullets) need a deeper “grip” than what FX rifling method is capable to do. Thats why we still see all these different barrels being made. When this said I am an admire of FX. They are innovative like no other. Something other airgunmakes could learn from.
I agree, but most of this new "technology" has been developed by trial and error by third party experimenters like Matt Dubber, Ted Bier, and others along side the manufacturers. Good for them, I say. But airgun manufacturers are rather small companies and don't have the resources to develop ballistic technologies under controlled laboratory conditions. We are, however, lucky that we've gotten this far. Methinks we still have a long way to go to develop this slug/barrel thing. Right now, we are limited in slug profiles due to the fact that they can't exceed a given length to fit into existing magazines. It is interesting to watch all this new stuff come into existence, but by wallet can't stand it.