Weapon Sway Unity3D

//============================================
// ATTACH THIS TO WEAPON
//
// ATTACH WEAPON TO PLAYER GAMEOBJECT
//============================================

using UnityEngine;
using System.Collections;

public class WeaponSwayScript : MonoBehaviour {

    public float mouseSensitivity = 10f;
    public float maxMoveAmount = 0.5f;
    public float smoothSpeed = 3f;

    private Vector3 startPos;

    private float factorX;
    private float factorY;

    public bool bRotate;
    public float smoothRotationSpeed = 2f;
    public float rotateAmount = 45f;

    //============================================
    // FUNCTIONS
    //============================================

    void Start()
    {
        startPos = transform.localPosition;
    }

    void Update()
    {
        // STORE MOUSE MOVEMENT AMOUNTS, SMOOTH WITH LERP
        factorX = Mathf.Lerp(factorX, -Input.GetAxis("Mouse X") * mouseSensitivity, Time.deltaTime * 10f);
        factorY = Mathf.Lerp(factorY, -Input.GetAxis("Mouse Y") * mouseSensitivity, Time.deltaTime * 10f);

        // CLAMP LIMITS
        if (factorX > maxMoveAmount)
            factorX = maxMoveAmount;

        if (factorX < -maxMoveAmount)
            factorX = -maxMoveAmount;

        if (factorY > maxMoveAmount)
            factorY = maxMoveAmount;

        if (factorY < -maxMoveAmount)
            factorY = -maxMoveAmount;

        // SET TARGET POSITION (START POSITION + MOUSE MOVEMENT)
        Vector3 targetPos = new Vector3(startPos.x + factorX, startPos.y + factorY, startPos.z);

        // APPLY POSITION TO WEAPON, SMOOTH WITH LERP
        transform.localPosition = Vector3.Lerp(transform.localPosition, targetPos, smoothSpeed * Time.deltaTime);

        // ROTATION
        if (bRotate)
        {
            float tiltAroundZ = Input.GetAxis("Mouse X") * rotateAmount;
            float tiltAroundX = Input.GetAxis("Mouse Y") * rotateAmount;
            Vector3 target = new Vector3(tiltAroundX, 0f, tiltAroundZ);
            transform.localRotation = Quaternion.Slerp(transform.localRotation, Quaternion.Euler(target), Time.deltaTime * smoothRotationSpeed);
        }
    }

}