I was not aware that they ended short of the barrel. I had assumed that theyu had run to the end. Am I overthinking this, or is it still a good idea in order to protect the barrels?
Briley used to offer the tubes out of two different materials...one lighter yet more expensive.
I had two sets custom fitted by Briley one for a 1879 Purdey hammer 10 ga. to 20 ga. another for a 1871 W.C. Scott hammer 12 ga. to 20 ga. both Briley sets were dead flush at the muzzle and both worked flawlessly...I even shot 2&3/4" 20 ga. 4 shot magnums in the 12 ga. to 20 set with no sighs of any problems.
I'm betting the mention of muzzle short tubes were not Briley hand fitted tubes.
In my opinion the 10 to 20 was too far a stretch the 12 to 20 was really nice.
My advice is go for it and don't listen to these typewriter X'Spurts.