Standard skeletal bone IDs in Apex Legends character models:

• Bone 8: Head / Helmet
• Bone 7: Neck
• Bone 5: Upper Spine / Chest
• Bone 3: Lower Spine
• Bone 2: Pelvis / Hip Center
• Bone 12: Left Shoulder
• Bone 16: Right Shoulder

Vector3 GetBonePosition(CPlayer* pPlayer, int boneId) {
    uint64_t boneMatrix = *(uint64_t*)(pPlayer + offset_bonematrix);
    Matrix3x4 bone = *(Matrix3x4*)(boneMatrix + (boneId * sizeof(Matrix3x4)));
    return { bone.m[0][3], bone.m[1][3], bone.m[2][3] };
}

Bone 8 for head and Bone 5 for chest covers 100% of aimbot targeting needs.

Bone matrices match Wraith, Pathfinder, and Octane models identically.