dillon777 wrote can i mod gun stats using gibb save editor

You have a couple options.

Option 1:
You can change the legitimate parts of a weapon by clicking on the arrows next to the fields such as the "Grip" or "Accessory #1" and selecting a different part that is displayed in the drop down menu. Usually it's a jakobs grip for assault rifles, sniper rifles, pistols, and shotguns. For rocket launchers it's a torgue grip and a torgue stock/exhaust that increases damage. Lastly, smgs benefit from a maliwan grip. You can also change the "Accessory #1" field to a different accessory such as a damage accessory. Some weapons don't have an option for a damage accessory so you can pick an accessory such as the "VerticalGrip" for shotguns to increase their pellet count or "multiplier".

Option 2:
You can add in extra barrels or other parts that don't normally belong that will make them stronger but will also make it considered a "hybrid" or "modded" weapon. These weapons have to be stored in the bank before saving and quitting and also inserted in the bank before loading via gibbed's for the gun to appear in game. You can replace parts such as the stock or sight if you don't care about appearance or you can simply use an empty field like the "Accessory #2" slot to add an extra barrel for damage. Usually people use a hammer buster barrel to increase base damage and a torgue/jakobs shotgun barrel to increase the pellet count/multiplier.

In Really Short Answer...... Yes!!