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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