In order to eliminate the interference of reactive armor to main jet for improving the ability that high explosive antitank projectile penetrating the explosive reactive armor, numerical simulations by AUTODYN-2D software was carried out to emulate Teflon jet initiating B explosive with shell, and penetration without detonation of B explosive with shell was achieved. The results indicate that the liner with the same cartridge, u²d decreases as cone angel increases, while u²d increases as cartridge decreases with the same cone angel. The initiating value u²d of Teflon jet to B explosive with shell is about 25. 538mm³ /µs², which is basically in accordance with 23mm³ /µs² put forward by Held.