They have been broken for 4 months since you broke it with the patch you've introduced Nuclear Winter.
https://www.reddit.com/r/fo76/comments/bzqpc2/new_heavy_weapon_bug_on_spin_up_heavies/
Looking down the sight while spinning up makes minigun, gatling laser and gatling plasma unable to shoot any bullets.
Of course, you can bypass it by looking down the sight before the spinning up and shooting hip fire but it was working fine before NW patch came.
Also, please make fusion cores and plasma cores on these guns to reload ammo with lesser conditions like you've done with fusion cores on power armor. Producing and carrying so many uneven fusion cores is not feeling nice. TY
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