When I first bought my 40 Glock I read several stories of shooting lead that resulted in kabooms. The issues ranged from unsupported barrels to the type of barrel used on the Glock.
Were they true? I don't know but for around $100 I bought an aftermarket barrel and shoot a lot of lead out of my Glock. It has been around 5 years and I have not had one issue shooting lead.
So did I have to do that? I still don;t know but there are hardly any if in fact any stories of Glocks with after market barrels failing with lead.
I was always told never to follow lead with a jacketed bullet so I never have.
Here is some information on the type of barrel used in the Glock. Maybe it will help you decide for yourself.
http://en.wikipedia.org/wiki/Polygonal_rifling