Ol' Painless does more damage per shot, has a faster rate of fire and reloads faster than the regular hunting rifle, and also has a good durability and can be repaired with ordinary hunting rifles. Since it is repaired with hunting rifles, it is easy to maintain. Ol' Painless is one of the few weapons with 0 spread, meaning with a 100 Small Guns skill, non-V.A.T.S. shots go exactly where you aim them.
Even though Dave claims he lost his hunting rifle stalking mirelurks, Ol' Painless is located in his safe right next to his chair. Dave's special key is required to open the safe. You can pickpocket Dave to find the key, you can complete the Election Day unmarked quest to get it, or you can get it through dialogue options and speech checks if you are doing the quest "You Gotta Shoot 'Em in the Head". You can also kill him to get it but everyone in the building will turn hostile. If you turn him hostile through dialogue you won't lose Karma. Taking the rifle will cost you Karma in any event, and residents will see it as stealing even if they gave you the key.
ps3xbox360 Even when given permission to raid Dave's safe, it will still be marked "red" as private property. Therefore, if you drop Ol' Painless and move the cross hair over it, the cross hair is red and "steal" is shown. Non-player characters will not turn hostile and you will not lose Karma when you pick it up. [verified]
ps3xbox360 Be careful storing this weapon because any unowned item may disappear from your storage. [verified]
ps3 If Pronto, Smiling Jack, Knick Knack, or Moira catch you pickpocketing them, they will take Ol' Painless like any stolen items, and will then have it for sale in their store. To avoid, just "fence" the item by selling it and then buying it back. [verified]
ps3 Sometimes Ol' Painless will just disappear from your inventory even if you have it equipped. This happens when exiting buildings,Fast traveling etc. It could happen in in-game days or weeks. [verified]