FX Smooth Twist and Polygonal barrels in .177 which is best?

If your barrel is a Smooth Twist and NOT a SmoothTwist - X, it is only rifled at the muzzle. and proved to be very accurate for specific diabolo pellets at low ft-lbs.

I own one (.177) but have never shot it. The gentleman I purchased it from is a fine marksman and told me that from 7 to 12 ft-lbs it shot very, very, well and was competitive. Above 12 ft-lbs with the same pellet you were better off using a slingshot.

Also, I have never disassembled the Smooth Twist barrel system, but it appears this old system doesn't use interchangeable liners. Or I need a special tool to remove the liner.

If your barrel is a Smooth Twist - X system then the liner is fully rifled and interchangeable.

I own three 600 mm .177 Smooth Twist - X barrel systems, each with a different twist rate but none are polygon rifled. I haven't seen a polygon rifled liner or know anyone who shoots one, as such I have no data to compare the two.
 
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Troy, thank you for the info. My barrel is a regular SmoothTwist, not the SmoothTwist-X. I want to shoot at close to 20 foot-pounds, so it sounds like I need to change the barrel for best accuracy. Any other comments would be appreciated.

Roger Barker
You should not need to change barrels. The original, solid ST barrels are, IMO, the best thing FX has ever produced. 20 fpe is standard power and should shoot very well in your Royale 400.
 
Troy, thank you for the info. My barrel is a regular SmoothTwist, not the SmoothTwist-X. I want to shoot at close to 20 foot-pounds, so it sounds like I need to change the barrel for best accuracy. Any other comments would be appreciated.

Roger Barker
The Smooth Twist barrels are very sensitive to pellet weight and size.

Primarily due to:

A. The amount of air passing the pellet in the smooth section if the pellet skirt diameter or thickness will not allow the pellet to expand enough to seal the bore.

B. The slow twist rates used.

The Smooth X barrel is basically just a current 10 Meter Precision Air Rifle barrel in reverse. The 10 Meter Rifle has a short amount of rifling at the breech and then smooth to the muzzle.

So testing various pellets is highly recommended as you go up in muzzle energy and/or projectile weight.
 
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Above 12 ft-lbs with the same pellet you were better off using a slingshot.
I have seen an FX or two at the Worlds in the hands of upper level shooters (12 ft-lbs) and rarely (with the same upper level crowd) in USA FT (20 ft-lbs). Heard the smooth twist did not do well at 20 ft-lbs, interesting to know they work well at 12 ft-lbs. I have only heard good things about these barrels at 'normal' speeds (non-field target velocities), no complaints from my FX Impact when tuned to what the pellets wants. Neat stuff Troy!
 
Well I just can't let this dog lay. Normally I would stay out of this kind of discussion, but I've been using an FX Royale 400 (.177 cal - 20 ft-lbs) for the last three years to shoot field target in the Hunter PCP class. So when the rumors start that these guns are not accurate at 20 ft-lbs, well that's just hooey. The Smooth Twist barrels are great performers and can easily hold their own with other FT contenders.
These barrels were designed to shoot JSB pellets, so I'd start with some of those. Personally I shoot Air Arms 10.3 because they're a bit more consistent in my gun.
Anyway here's a sped up video of 9 shots (why not 10, I lost count) I took tonight at 55 yds, very light breeze. The background target has 1" squares.
If you can shoot a slingshot better than this, I'll buy it.

T2.jpg


 
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Well I just can't let this dog lay. Normally I would stay out of this kind of discussion, but I've been using an FX Royale 400 (.177 cal - 20 ft-lbs) for the last three years to shoot field target in the Hunter PCP class. So when the rumors start that these guns are not accurate at 20 ft-lbs, well that's just hooey. The Smooth Twist barrels are great performers and can easily hold their own with other FT contenders.
These barrels were designed to shoot JSB pellets, so I'd start with some of those. Personally I shoot Air Arms 10.3 because they're a bit more consistent in my gun.
Anyway here's a spead up video of 9 shots (why not 10, I lost count) I took tonight at 55 yds, very light breeze. The background target has 1" squares.
If you can shoot a slingshot better than this, I'll buy it.

View attachment 590655

Well I just proved to myself what others here probably already know ... I am full of poope.

According to my .177 Impact M3 pellet testing spreadsheet where I have recorded 23 different brand/size/weight pellets tested for sub MOA 5 round groups indoors at 20 yards over the full range of Macro settings ...... I have one pellet that groups </= 0.199" EtoE at </=12 ft-lbs. and 2 different pellets that group </= 0.199" EtoE at >12 </=20 ft-lbs.

So, If it were me, I would say a SmoothTwist X is probably no less pellet sensitive than the original SmoothTwist.

I use a Targetshooting.com 1 piece rest designed specifically for group shooting when pellet testing.
 
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Well I just can't let this dog lay. Normally I would stay out of this kind of discussion, but I've been using an FX Royale 400 (.177 cal - 20 ft-lbs) for the last three years to shoot field target in the Hunter PCP class. So when the rumors start that these guns are not accurate at 20 ft-lbs, well that's just hooey. The Smooth Twist barrels are great performers and can easily hold their own with other FT contenders.
These barrels were designed to shoot JSB pellets, so I'd start with some of those. Personally I shoot Air Arms 10.3 because they're a bit more consistent in my gun.
Anyway here's a sped up video of 9 shots (why not 10, I lost count) I took tonight at 55 yds, very light breeze. The background target has 1" squares.
If you can shoot a slingshot better than this, I'll buy it.

View attachment 590655

Glad you piped up and kicked the dog!! Funny how things get started and just snowball into fact from being essentially fiction.