Hey guys i just have some sugestions about this unit.
1st) as i get it its a shotgun unit (i think if not a minicannon) so if it is a shotgun unit probably they must have very close range (and not to mention the spray that kills the men way behind)
if it is a minicannon (handcannon) unit then i think the range is fine

2ond) Ammo: okay i love using them they are devasteting but typicaly i found that i can destroy almost all the enemy army if i use them properly (ex a battle with the enemies around 1700 men blunderbuss can kill around 800+ of them ) . So i think if i had less ammo probably it would force me to use them only to units that i want to get rid off and not waste my ammo to everything i can see and after the battle to have killed almost all the army with blunderbuss and have used less than half ammo ( i gues its balanced cause they are best at siege and bridge defence in the field they can be used but not so much) and considering the logical sight of the view with so much ammo they must have a barrel of bullets next to them to satisfy that much ammo tha is been used. their ammo should be around 10-16 shots (in my opinion cause i like hardcore 7-10 shots at most)

3rd) probably they need to have reduced just by a bit their running speed (they are slow because they are dwarfs but the extra gun and ammo should wait a bit more (franly i am not sure of this)

Actualy this would make things more chalenging for you rather the AI (the AI cant seem to use them as efectively as the player) and it would force you to use them where the situation demands it (ex i should let marauders live and wait for the chossen knights to kill as many of them and then choose another unit that probably will make your live hard and if i have some more ammo use them in my lossing flank etc)

What make me though of this: my dear orcs and goblins in the south, my dear chaos in the north witch are both dead (well slanesh still waits to have some fun )