.177cal Smooth Twist X Barrel Pellet Preferences?

Tough one to answer, in the UK with energy set to 12FT the reg has to be run at 60 bar to keep it legal at max hammer, but you need to reg to run at 90-110 bar in .177 to get the Crown to group, which means that the hammer spring tension needs to be run low, giving a kind of sluggish effect if that makes sense.

The JSB Express will shoot fine at these levels, I have some RS express but have not tried them TBH.
 
My .177 Impact X shoots the 8.4 JSB's pretty good. If they were the only pellets available, I could live with the groups. But the way it shoots with 10.34 JSB's is the reason I wanted one for so long. Mine is 18 ftlbs. Don't think I'll be turning it down either, I have other guns for that.

I have a Crown in .25 for power I purchased the .177 specifically to be my gun for lower power.
 
I understand why you want the gun @ 12ftlbs, I have AOA build me a Brocock Bantam @ 12ftlbs for the massive shot count and to be my backyard gun I don't need full power. I think though the Smooth Twist and Smooth Twist X barrels need more power behind the pellet to be accurate. If you come up with a combination that works at lower power , please let us know. My guess (and its just a guess) is that the UK version comes with a different barrel than the version we get here in the U.S. ? Maybe when FX gets all the X barrel liners on the market, they will have one available for those of us that would like to take the gun in the opposite direction than most people do as the maximum the gun can do seems to be what most want.
 
Shot these groups last night from my .177 Impact X. Shot with JSB'S in 10.34 gr reg @ 100 bar and hammer spring set on Max. These were not shot off the bench but from a bucket and shooting sticks (HFT ) @ 30 yards-each target is a full magazine of 21 shots and except 2, all can be covered with a penny, that puts the center to center at about.500 May not win EBR but that's better than my previous gun I use for HFT . More than happy with it's accuracy.
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