A baler apparatus includes a baling chamber (2) with at least one adjustable wall (4) for adjusting the compression of a body of bale material (18). A reciprocating plunger (10) is operable to compress the bale material (18) and a binding device (17) binds the compressed material to form a bale by the use of twine loops (22). An adjustment means in the form of a guide or rollers (41) is provided for the purpose of varying the length of the twine loops 22a, 22b) when binding the bale in order to reduce compression within part of the body of bale material and avoid twine breakage which can otherwise occur as a bale is ejected from the baler.