A straight cutting tip for a straight bore subcutaneous implantation instrument is provided. An incising shaft body defines an axial bore extending continuously throughout the incising shaft body's length. The axial bore is open on both distal and proximal ends of the incising shaft body and has a non-circular cross section of at least five millimeters. A beveled surface is transversely formed beginning on a top surface and ending on a bottom surface of the distal end of the incising shaft body. A straight and sharpened cutting edge with rounded ends on each side curves inwardly towards the proximal end of the incising shaft body. The cutting edge is defined only along a bottom distal edge of the beveled surface. An attachment point is formed on the proximal end of the incising shaft body.