Diameter of carbon fiber rod to check moderator alignment?

[Ultralight]

I would like to check the alignment of mounted moderators on .25 barrels. What is the diameter of a carbon fiber rod I should get to do this check? I'd like as large a diameter as possible that will still fit?

Thanks for any insight.

 

[nervoustrig]

That’s the right idea but it’s easier said than done. If the free end has more than the slightest amount of play, you can try rocking it back and forth to interpolate where the approximate midpoint is. Or you can wrap the rod in 2 places (breech and muzzle) with tape until it is a slip fit so it stays roughly centered.

 

[beerthief]

IF you find that the moderator is indeed slightly crooked BUT your pellet does not clip it , exactly what are you going to fix and how ?
OR
simply if the pellet does not clip . don't fix it .
( ok smart azz remark sorry )

 

[ctshooter]

Not to be snarky - but a .25 barrel is - .25" You'd have to modify the fit as noted above.

Do you expect clipping? Sometimes if you open up the moderator you can see a mark from the clipping.

 

[6gun]

IF you find that the moderator is indeed slightly crooked BUT your pellet does not clip it , exactly what are you going to fix and how ?
OR
simply if the pellet does not clip . don't fix it .
( ok smart azz remark sorry )

The exiting air having an uneven path caused me issues with accuracy. So I gambled on thread play and put a feeler guage behind the mod till I was happy, removed the feeler guage and cut a sliver off of it for permanent use to take advantage of the thread play. Groups got better.

 

[beerthief]

The exiting air having an uneven path caused me issues with accuracy. So I gambled on thread play and put a feeler guage behind the mod till I was happy, removed the feeler guage and cut a sliver off of it for permanent use to take advantage of the thread play. Groups got better.

Interesting , thanks

 

[subscriber]

All barrels are not equal. Lothar Walther barrels have larger land and groove diameters than other airgun barrels. Some barrels are heavily choked and others not at all.

So, Nervoustrigger's suggestion above, to wrap a slightly undersized rod with tape to create a custom fit in your barrel is a good one. A brass or steel rod (OK if you wrap it in tape) may be stiffer than CF. In any event, roll the rod on a flat surface to check its straightness before using it.