"This new pulse rifle can be rewarded by playing this week Sunless Cell Nightfall but here is a catch. The preview display that indicate a estimative of how much bullets will be increased are bugging severely and the second column of weapon perks is causing this oddness behavior.

Make sure not to have 'Appended Mag' with 'High-Caliber Rounds' or you will be losing over 13 bullets and by worst case when using weapon modifiers to increase the magazine. The loss is over 15 bullets."