I've owned both my tika t3, and t8 from new,and being the over barrel mod I've noticed it marks the last few inches where it's tight on the barrel.
This hasn't in all the years I've owned both affected accuracy in any way.
Is there any real need for a rear bush between the mod and barrel?
If there is,who can make them or take off a few thou.
Even without the bush it fits real snug,but I don't know what sort of movement there might be.