What are the stats of companion NPC's default weapons?

I know that the various companion NPC's all come with a 'default' weapon, which doens't use ammunition. That's pretty great, and all, but some of the weapons they are carrying... do not look very good. For instance, it seems that Nick Valentine is using a beat up old Pipe Revolver.

Is there any way to see the stats for these default weapons, so that I can better assess whether I'd rather part with some hard-earned ammunition to spare them the indignity of their defaults?

(Or just hand them Grognak's Axe and the Grognak costume and tell them to go smash things...)

No, there is no way to see what the stats of each companion's default weapon are as there is no way to get this weapon to show in their inventory (unlike their clothing/armor). Even if you equip them with another weapon, their default doesn't appear in their inventory.

While there is no way to see the default weapon damage for each companion, you are able to see their default weapons on their individual pages on the Fallout 4 Companion wikia.

Using the damage output numbers of their default weapon and their SPECIAL stats, it would probably be possible to compute their default damage output, but you might as well just give them better equipment.