I upgraded my 15-22's firing pin to the Volquartsen.

I didn't know to use a brass punch, so my steel punch caused mushrooming on the firing pin roll pin. I used a brass punch without any problems.

From an AR15 build video I saw last night, I just learned about roll pin punches which have a dimple/protrusion that fits into roll pin hole. Those don't appear to be made of brass.

However, one of my friends, a retired engineer who admittedly hasn't built or serviced an AR, suggested that the roll pin punches somehow could cause the roll pin to expand outward, notwithstanding the fact that roll pins are made of softer material than, say the 15-22's bolt assembly.

For future AR15 builds and (hopefully not) any future 15-22 firing pin roll pin removals and installations, are roll pin punches a good thing to have?