Tuning FX Liners - .25x700 - twist rate comparison

My Impact MK2 arrived with a .25x700 STX-A liner twist rate 1:27.
I fell into the hype with slugs, and bought the .25x700 Superior Heavy with twist rate 1:18.
This year entire season I was shooting slugs @ 50 and 100 Meters paper rings (only), and I am not convinced. I tried all ZAN's 37-41-44-46 gr. I have not tried other brands I can admit.
I mean the scores are OKish but not really an eye opener when I comparing the overall accuracy to the 33.95 pellets, MK1 or MK2.
I don't know if this is due to speed 960 to twist 1:18 ratio, but I feel like going back to 1:27 STX-A's.
Any thoughts?
 
The new Superior STX in .25 are 1:24 twist rate. Might be worth a try 🤔 . I have it in 600mm in my M3 and it loves the MKII 33.95 . I also have the 600mm 1:18 but haven't been motivated to install it because it shoots the 33.95's so well. I have played with lighter Nielsen slugs up to 33.95 Knockouts, nothing "heavy" and, like you, they were OK, sometimes close to the MKII's out to 75yds but never matching the pellets for accuracy.

Patrick
 
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I have an older Slug A liner in my .25 Impact Slugger. It loves the NSA 38.9 (965 fps) and 43.5 (915 fps). I’ve tried the ZAN 41s but it didn’t like them. The Slug A is 1:21 twist if I’m not mistaken. Also, the Superior Heavy barrel is “tighter” than the Slug A FYI. I really like this setup because with a 50Y zero I can dial out to 320+ yards. Athlon Midas BTR gen2 4-27x MIL scope.

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At my club we have a 2-3-400 meter range, but need a mandatory course in order to shoot there. I asked another day couple board members I want to take a course but when I told them I want to shoot an airgun they just rolled their eyes :). So I need to ask the club board officially to investigate.
But I already decided I am pulling out from slugs shooters club, too much work.
100 meters and pellets, and my favorite range is the 22LR silouettes, if you see there paper targets hanging you can know for sure that I am there.
 
My Impact MK2 arrived with a .25x700 STX-A liner twist rate 1:27.
I fell into the hype with slugs, and bought the .25x700 Superior Heavy with twist rate 1:18.
This year entire season I was shooting slugs @ 50 and 100 Meters paper rings (only), and I am not convinced. I tried all ZAN's 37-41-44-46 gr. I have not tried other brands I can admit.
I mean the scores are OKish but not really an eye opener when I comparing the overall accuracy to the 33.95 pellets, MK1 or MK2.
I don't know if this is due to speed 960 to twist 1:18 ratio, but I feel like going back to 1:27 STX-A's.
Any thoughts?
The Standard Superior 700mm liner loves the Nielsen 33.5 gr. slugs. They don't mind being pushed fast either.
My Impact MK2 arrived with a .25x700 STX-A liner twist rate 1:27.
I fell into the hype with slugs, and bought the .25x700 Superior Heavy with twist rate 1:18.
This year entire season I was shooting slugs @ 50 and 100 Meters paper rings (only), and I am not convinced. I tried all ZAN's 37-41-44-46 gr. I have not tried other brands I can admit.
I mean the scores are OKish but not really an eye opener when I comparing the overall accuracy to the 33.95 pellets, MK1 or MK2.
I don't know if this is due to speed 960 to twist 1:18 ratio, but I feel like going back to 1:27 STX-A's.
Any thoughts?
The Standard Superior 700 mm liner loves the 33.5 gr. Nielsen slugs. They don't mind being pushed fast either. Not sure if you are up to getting another liner though.

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