A Very Interesting Pen.
Glorious Birds Eye Maple Blank,
Nice Profile, though IMO the Transition From the Maximum Diameter of the Blank, to the Clip End Diameter, is a little Abrupt, it could have been Longer, just as you did at the Nib End.
This is something that with Experience, you will find the Confidence, and remove any Fear of Blowing the Blank, because you have taken it too close to the Tube.
Rest assured provided that the Tube is Glued Properly, and you are not working with a Brittle Blank Material, by turning the Blank to the Bushing Diameter, with a Gentle Transition, you will not Blow the Blank.
I look forward to seeing some more of your Work,
Congratulations,
Brian.