A co-forged iron type golf club is disclosed. More specifically, the present invention discloses a co-forged iron type golf club with the body portion made out of a first material and at least one weight adjustment portion monolithically encased within the body portion of the co-forged iron type golf club head without the need for secondary attachment or machining operations. The present invention also includes a combination of lightweight and heavy density weight adjustment portions that could be introduced towards the final forging step of the co-forging process, allowing for more flexibility in the selection of materials.

A golf club head includes a striking face having a face center and defining a face plane. A vertical center plane is perpendicular to the face plane and passes through the face center. The golf club head further includes a hosel configured to receive a shaft and defining a hosel axis. The golf club head mass is between about 250 g and 320 g, a loft, L, is no less than 39°, a club head center of gravity is spaced rearward from the face plane by a distance, D5, such that D5≤7.69 mm−0.074 mm/°*L, and spaced from the vertical center plane by a distance, D7, that is no greater than 5 mm. A moment of inertia, Iyy, measured about an axis extending in the heel to toe direction and passing through the center of gravity, is no less than 1000 g*cm.sup.2.

A co-forged iron type golf club is disclosed. More specifically, the present invention discloses an iron type golf club head from a pre-form billet that already contains two or more materials before the actual forging process resulting in a multi-material golf club head that doesn't require any post manufacturing operations such as machining, welding, swaging, gluing, and the like. The resultant golf club head may be capable of achieving center of gravity locations previously unachievable without utilizing this co-forging technique. The resultant golf club head may be used to create a set of golf club heads with center of gravity locations that are more advantageous throughout a set of golf clubs.

A golf club head has a hollow therein and comprises a face portion, a crown portion and a sole portion. The face portion comprises a central zone including a face center, and a peripheral zone surrounding the central zone. Each of the central zone and the peripheral zone has a flexural stiffness defined by E×t.sup.3/12, wherein E is the Young's modulus (GPa) and t is the thickness (mm) of the zone concerned. The ratio sc/sp of the flexural stiffness Sc of the central zone to the flexural stiffness sp of the peripheral zone is 5.0 to 55.0.

An iron-type golf club incorporating an aperture extending through the shell on the sole. The location and size of the aperture selectively increase deflection of the face.

An iron-type golf club incorporating an aperture extending through the shell on the sole. The location and size of the aperture selectively increase deflection of the face.

A co-forged iron type golf club is disclosed. More specifically, the present invention discloses an iron type golf club head from a pre-form billet that already contains two or more materials before the actual forging process resulting in a multi-material golf club head that doesn't require any post manufacturing operations such as machining, welding, swaging, gluing, and the like. The resultant golf club head may be capable of achieving center of gravity locations previously unachievable without utilizing this co-forging technique. The resultant golf club head may be used to create a set of golf club heads with center of gravity locations that are more advantageous throughout a set of golf clubs.

A golf club head includes a metallic head body having an opening, and an FRP member fixed to the head body so as to close the opening. The FRP member is a fiber-reinforced plastic including fibers and thermoplastic resin. The head body includes a support portion around the opening. The support portion has a first surface for supporting the FRP member. The first surface is provided with at least one narrow groove having a groove width of 20 to 80 μm and a groove depth of 100 to 400 μm, and a part of the thermoplastic resin of the FRP member is solidified inside the at least one narrow groove.

Embodiments of putter-type golf club heads with adjustable loft and lie and methods of manufacturing of the same with adjustable loft and lie are generally described herein. These embodiments relate in particular to a putter-type club head with an adjustment portion that allows a user to change the loft and lie. The separate adjustment portions of the putter-type club head can couple the upper hosel to the body at a plurality of positions. An insert part of the adjustment portion has an upper section for receiving the upper hosel portion, a middle section, and a lower hosel portion. The sections of the adjustment portion can be coupled together by a fastener so that the sections are rotationally movable.

A ball striking device, such as a golf club head, has a face with a striking surface configured for striking a ball; an elongated channel extending across a portion of the sole, wherein the sole has an elongated channel recessed from adjacent surfaces of the sole that has a plurality of troughs within the channel to help improve the efficiency of the impact with a golf ball.