Why is the Smooth Twist barrel only accurate with JSB ?

I've thought about this too, could it be that JSB's are pure lead?

I thought the big selling point of Smooth Twist Barrels is they aren't pellet picky or not as picky as LW barrels. But I do find that I shoot JSB pellets through all my rifles, FXs, Daystates, Crickets, Air Arms and Hatsans because the JSBs seem to be the most accurate pellet through all of them.

As for FX giving a choise of barrels that aren't their own ST, I don't see that happening since they make such a big selling point about their ST being so accurate.

I wish the ST were accurate with other pellets,but with mine, it shoots like crap with just about everything else. Liked H&N Baracudas, but not as well as the JSB domed.

Jsb's are best in my 22, i tried 4-5 others, a couple would be ok for hunting but not target shooting. I havent tried anything else in the 25.

Wingman had an interesting post on pellet head size and accuracy in smooth twist barrels. The 2 FX guns I have owned only shot JSB well. Everything else shot like it had a mind of it's own. In all fairness my EDguns, Taipan, Vulcan, Weihrauch HW100 and Cricket only likes JSBs. I find it odd that my German PCP gun only likes Czech pellets. If they ever stop making JSB I'll be screwed. The JSB pellet is the gold standard, everything else is second best. So I guess does it really manner that most guns only like JSB?

I think the JSB's are the softest lead pellet I've ever used. Maybe this has something to do with it?

Not true in my rifle. Hi guys, I have a FX Royale 400 regulated. I shoot RWS Superdomes, and they shoot hole in hole at 40 yards. I also shoot JSB Heavies out of my gun and they do very well.

hope this helps.

Biagio

My Royale 400 .177 shoots very nicely with H&N Bara match and FTT's, just a matter of finding the pellet headsize that the ST barrel was happy with, in my case it was 4.51, not sure if I will bother playing around with other pellets.

My Bobcats likes Bisley magnums and fx pellets. 

This is the factory visit of FX where Terry Doe from UK met Fred and saw the process where he makes the smooth twist barrel. If you start watching from 7:46 minutes onwards, Terry claims that the smooth twist barrel will give you hole in hole results provided the pellet is of SUPERIOR QUALITY. I believe him cause if you do look at some people who use the bobcat, they swear by the H&N Pellets, RWS and JSB all of whom are considered to be high quality pellet makers. I know that several people prefer JSB but the ones who use H&N also swear by their accuracy out of the smooth twist barrel. 

It it would be a fun experiment to pick up say 4-5 fx guns with the smooth twist and run a series of tests on whether the JSB are the most accurate or others as well. My guess is that any high quality pellet will do well out of the ST. I guess most people go straight to JSB and therefore claim it's the most accurate of out their gun. Also I did hear a long tome back that given JSB pellet quality and easy availability most gun makers were designing their barrel keeping JSB in mind and therefore these pellets do much better out of most guns. 

What air rifle is not overpriced?

I own two different FX rifles with 22 caliber smooth-twist barrels and both rifles shoot every type of pellet I have tried very well, with one exception; wadcutters. I cannot get wadcutters of any brand to shoot accurately in the rifles. But, I have shot domed H&N, JSB, Benjamin, RWS and probably more I have forgotten about and they all worked well, especially once I found the power setting (i.e: velocity) each pellet type preferred. The smooth-twist barrels are great!!

I don't think it's a problem of the barrel being fussy, but of the shooter/owner being fussy. I have two FX airguns; Royale 400 .177 and Royale 500. I can tell you that my guns are not fussy at all. The 400 likes JSB, H&N, Crosman and RWS. And the 500 likes JSB and Benjamin's equally. But I think it comes down to the accuracy everyone is searching for. Years ago 1-1/2 inch groups at 30 yards was ok. Now a lot of people want 1/2 inch groups at 100 yrds. These are pellet guns. Good ones. Even great ones sometimes. But they are still pellet guns. I think we sometimes demand more out of them and the pellets we feed them than they are really capable of.

Keith.

As a counterpoint, if the Smooth Twist barrel "only" shoots JSB pellets and nothing else, then tell me why FX sells the FX Smooth Twist pellets?

They are neither repackaged JSBs nor even a diabolo for that matter. They are repackaged Defiants (now H&N Snipers) and are cylindrical.

Dont believe me? Have a look for yourself.

Manny, Benjamins do well from my FX Elite ST barrel
Three at 50 yards: Hope it still shows for you.
http://vidmg.photobucket.com/albums/v392/Kyogle/FXST25Elite3Benjamindomesat51yardsonramsilhouetteJan2012.mp4

Kodiak Barracudas do similar. But over a number of groups the Kings do shade them both.
I think some shooters don't realise that the heavier slower pellets require great attention to follow- through.

Edit: The Predator Polymags .25 are very accurate from the Elite ST barrel. They hold up to 70+ yaeds against Kings in good air, drift more in wind but stll group.
This at 50 yards:
http://vidmg.photobucket.com/albums/v392/Kyogle/FXST25JSBPolymags3at51yardspigsilhouetteJan2012.mp4

Kind regards, Harry.