Yes, most definitely. The book pax referenced discusses the issue in detail.Has anybody ever run a controlled experiment to lead up a Glock barrel to a known degree and see what happened?
The author of the chapter in question began researching the problem after blowing up one of his own Glocks. He had the means at his disposal to do so and I get the feeling that he initially felt he would be able to show that there was a problem with the pistol.
After determining what had caused the problem, he then tried to develop a reliable process/rule for using lead bullets that would eliminate the possibility of a catastrophic incident. Instead, the result was that he chose to shoot only plated or jacketed bullets in Glock factory barrels from then on.
His testing (involving shooting many thousands of rounds fired with instrumentation) revealed that the leading progressed at an alarmingly rapid rate in some Glocks while other apparently identical Glocks behaved much differently when using the same ammunition.
This issue is addressed as well. The Glock bores have a smaller cross-section than a typical land and groove barrel and all else being equal will tend to have discharge pressures 5% to 7% higher as a result. That's before any leading at all.I have looked and looked at barrel drawings and cannot find a "passageway."
Since current practice is to make bullet diameter = groove diameter and SAAMI specifies the barrel cross sectional area including the grooves, heavy leading in the grooves does indeed "narrow the passageway."