Pellet clipping moderator

Usually for me just thread alignment or debris, some are just made to tight?some work fine on some and same one will clip on another gun? I usually buy a caliber big or open them up .020” if they clip, not a big deal. My best success is with a 25 cal for 22 cal, works great, they don’t need to be slip fit to work great, the worst ones are the one that barely clip sometimes, not all the time? Will drive you crazy. Hope that helps. 
 
There are several reasons.

thread on barrels not concentric to the bore

thread in mod mot concentric to the holes in the baffles 

crown of barrel not cur square to bore

wrong calibre mod 

baffle in mod has tilted inside

wadding material has become displaced 

if it’s an fx with barrel liner system, the liner lock nut is not aligned correctly 



Bb
 
Bucketboy, can you explain the alignment process on the FX liner?




I can only go by mine, there are 3 parts that can cause clipping, the thread on the lock nut has to be concentric to the liner, the thread inside sleeve has to run concentric to the liner, when fully assembled everything has to align perfectly together. The mod then has to align perfectly with that... mine doesn’t, something is slightly out of skew, looking down from the breech end of my barrel with the mod attached, I can see that the mod sits at an angle.

I have some materials on order to try and rectify this, I will report back when done.



Bb