Index an Airgun barrel ?? Really

Nope.

If your transfer port is fixed (machined into the barrel) like it is in many rifles you can't index without some major modifications.

STX liners within the outer barrel sleeve, Weihrauch hw100 barrels, and RAW barrels with thimbles are some you can index. Probably a fair few more I'm not remembering 



I was cleaning my HW100 BP-K the other day and the barrel twisted on me. Is this normal or did something loosen up? Should I test shoot it to see if the poi has changed, and if so, should I "index" it to find the most accurate position?


 
Nope.

If your transfer port is fixed (machined into the barrel) like it is in many rifles you can't index without some major modifications.

STX liners within the outer barrel sleeve, Weihrauch hw100 barrels, and RAW barrels with thimbles are some you can index. Probably a fair few more I'm not remembering 



I was cleaning my HW100 BP-K the other day and the barrel twisted on me. Is this normal or did something loosen up? Should I test shoot it to see if the poi has changed, and if so, should I "index" it to find the most accurate position?


That's normal my brand new BPK barrel was loose when I got it just unscrew the tube and tighten the set screw doesnt matter index position for that gun.
 


I was cleaning my HW100 BP-K the other day and the barrel twisted on me. Is this normal or did something loosen up? Should I test shoot it to see if the poi has changed, and if so, should I "index" it to find the most accurate position?

Just snug up the bottom attaching screw. I'm sure some would argue that the Weihrauch system of using a single grub screw to attach the barrel is not the best. May be, but I've never had a problem with mine. But I am sensitive to putting a lot of torque on the barrel. When I was removing the glued-on factory moderator, I removed the barrel and held it in a vice. And when reattaching the moderator, I never use more than light hand tight fit. You can certainly play with indexing it, but I think you will find it a waste of time.