I believe HUF laws varies from state to state and since I belong to West Bengal wont the gift deed make a difference so that the others wont have any claim on the deed gifted to my father.
HUF properties or law do not differ from one state to another as you think.
This property shall come under HUD.
This property shall be your grandfather's own and absolute property which upon his intestate deaths, shall devolve equally on all his legal heirs.
Therefore your grandmother can acquire only her own legitimate share i the property and she can dispose or transfer it in any manner and to the person of her choice.
Please be aware that your paternal aunt and the legal heirs of yor deceased paternal uncle are entitled to their legitimate share in the proprieties.
They cannot be ignored are deprived of their rights in the properties, they may go to the court seeking their respective shares.