Hi all, this is my first post. I hope this hasn't been covered already, and if it has please tell me. I recently purchased two maverick 88's for my brothers for Christmas, one from fleet farm and one from wal-mart. Both are the same model (12 ga. w/ 28" bbl) but have different fore ends (one is a standard sporter and the other is the ribbed police style one). The issue is that the one with the ribbed police style fore end has a really stiff, gritty action when you work the pump, while the one with the sporter style is really smooth. I'm wondering if anybody else has had this issue. I took them both apart and the both look the same, nothing looks broken. The one that is smooth was significantly more lubricated when I took them apart. I cleaned them both, and while it made it slightly better, it's still really gritty. Any help with this issue would be greatly appreciated.