I use a good bearing grease and keep them tight. There is no reason for a tube to blow out if it and the barrel are undamaged and it is properly installed (that is, kept tight in its threads and in contact with the shoulder, as pointed out earlier).

Screw choke barrels are shot tens of thousands of times each week and this is a relatively uncommon (although not unheard of) occurance. Hardly the Emperor with no clothes, I should think.

Cheers

Cheers

Stephen