FX FX King 177

EPG said:

Regarding optimal velocity for the 13.4g JSB/FX/AA pellet…

Looking at the 40 Yard Challenge leaderboard, you will note excellent scores with the 13.4s - always with velocity between 790 to 840fps. Optimal seems about 825fps.

These results are across a variety of rifles/barrels: FX, RTI, Thomas, RAW.

I‘ve had excellent results with my FX Dreamline Classic with 500mm SL barrel shooting the 13.4s. Regulator pressure is 95bar.

The 10.3g can be shot over 900fps and retain high accuracy. The 13.4g seem to lose accuracy above 840fps.

Hope this data helps,

-Ed
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cavedweller said:

But in HFT 13.4 should stay below 815 FPS

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mtm100 said:

Well I think I figured it out. It’s the fx barrel as suspected. I just finished adapting a Walther poly barrel to the king. Now shoots typical match scores. Dropped 2 points out of 60 at 25 yards. That’s pellets right out of the tin. I pushed a few pellets thru the STX liner and it had several tight spots. In my opinion the king is a great gun in need of a good quality barrel. It can deliver a lot of power so I may try a 30 cal barrel retrofit next.
Heres some pics.
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mtm100 said:

While I kind of agree. Fx liners are rolled on the outside to make the rifling. Cut rifling can be rough from the transition lands to grooves. That’s all your soothing out by polishing. The inside of a fx liner should already be smooth as no machining has been done on the bore of the liner.
I have no idea why I can feel tight spots of if that’s why my gun shot poorly. But a conventional walther poly cut barrel shoots about as good as it does in my RAWS and Thomas’s. Now my king leaked from new UA is sending a new main valve. I made this tool to get the old seat out.
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mtm100 said:

While I kind of agree. Fx liners are rolled on the outside to make the rifling. Cut rifling can be rough from the transition lands to grooves. That’s all your soothing out by polishing. The inside of a fx liner should already be smooth as no machining has been done on the bore of the liner.
I have no idea why I can feel tight spots of if that’s why my gun shot poorly. But a conventional walther poly cut barrel shoots about as good as it does in my RAWS and Thomas’s. Now my king leaked from new UA is sending a new main valve. I made this tool to get the old seat out.
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