Open weapon.dat with notepad replace these lines:

$ PISTOL			INSTANT_HIT	25.0 30.0	346	-1		2	colt45		17	 25		0.25  0.05  0.09    0  0	0.75 1.0 	 6 17  6     6 16  6  99	3033
$ PISTOL			INSTANT_HIT	30.0 35.0	346	-1		2	colt45		17	 25		0.25  0.05  0.09	1  40	1.0  1.0 	 6 15  6     6 15  6  99	3033
$ PISTOL			INSTANT_HIT	35.0 35.0	346	-1		2	colt45pro	34	 25		0.25  0.05  0.09	2  999	1.25 1.0 	 6 18  6     6 17  6  99	3833
$ PISTOL			INSTANT_HIT	30.0 35.0	346	-1		2	colt_cop	17	 25		0.25  0.05  0.09	3  5000	1.0  1.0 	 6 15  6     6 15  6  99	7031


with these lines: 

$ PISTOL			INSTANT_HIT	25.0 30.0	346	-1		2	colt45		20	 22		0.25  0.05  0.09    0  0	0.75 1.0 	 6 17  6     6 16  6  99	3033
$ PISTOL			INSTANT_HIT	30.0 35.0	346	-1		2	colt45		28	 33		0.25  0.05  0.09	1  40	1.0  1.0 	 6 15  6     6 15  6  99	3033
$ PISTOL			INSTANT_HIT	35.0 35.0	346	-1		2	colt45pro	40	 40		0.25  0.05  0.09	2  999	1.25 1.0 	 6 18  6     6 17  6  99	3833
$ PISTOL			INSTANT_HIT	30.0 35.0	346	-1		2	colt_cop	8	 37		0.25  0.05  0.09	3  5000	1.0  1.0 	 6 15  6     6 15  6  99	7031
