The influence of annealing temperature on mechanical properties of C10100 copper when used as a shaped charge liner has been investigated. The cold worked liners manufactured by spinning technique are annealed at temperatures 200 to 600 oC to obtain grain sizes 10.6 to 49.4 µm. The Zerilli-Armstrong model is used to calculate the necking strain and the velocity difference between jet fragments (V_PL) using Kolsky approach for copper with grain sizes from 10.6 to 49.4µm; which were found 96.1 and 99.7m/s; respectively. Besides, Autodyn has been implemented to estimate the jet velocity, temperature and its penetration into 1006 steel targets. The effect of the liner grain size has also been confirmed by the static firing of these shaped charges including liners with different grain sizes after filling with waxed HMX. Results showed that the measured penetration depths increase from 12.63 to 13.77cm into 1006 steel targets when the yield strength of the copper liners increases from 69 to 95 MPa; respectively. This effect was accounted by incorporating the liner yield strength values within the well-known Allison-Vitalli formula, which accounts for this variation in the penetration tests when liners with different grain sizes and different yield strengths are tested and regarded.