Bullets, ect.

Comparison of different bullet sizes

Common calibers in inches and in their metric equivalents

US caliber	Metric Equivalent	Typical Actual Bullet Dia.	Misc.
.17	4.4 mm	0.172 in
.177	4.5 mm	.177 lead, .175 BB
.20, .204	5 mm	0.204 in
.22, .218, .219 .220, .221, .222, .223, .224, .225, .226	5.5, 5.56, 5.7 mm	0.223-0.224 in	.22 Caliber Slug
.228	none	0.228 in
.24	6 mm	0.243 in
.25	6.35 mm	0.25 in, 6.35 mm
.257	6.5 mm	0.257 in, 6.527 mm	typical 25 cal, not normally called 6.5
.26	6.5 mm	0.264 in, 6.7 mm	cartridges commonly known as 6.5
.27	6.8 mm, 7 mm	0.277 in, 7.035 mm	Is not called 7 mm
.28	7 mm	0.284 in, 7.213 mm	Is commonly called 7 mm
.30	7.62 mm	0.308 in	American ".30 caliber"
.30	7.62 mm	0.311 in	Other ".30 caliber"
.32, .327	7.65 mm	0.309 - 0.312 in
.32, .325	8 mm	0.323 in
.338	8.58 mm	0.338 in
.38, .380, .357, .35	9 mm	0.355-0.357 in
.38	10 mm	0.400 in
.40	10 mm	0.400 in
.404	10.25 mm	0.423 in
.405	10.75 mm	0.411 in
.408	10.4 mm	0.408 in
.41	10.25 mm	0.410 in
.416	10.6 mm	0.416 in	Barrett Industry sniper round
.43	11 mm	0.43 in Sl
.44	10.8 mm	0.427 - 0.430 in
.45	11.45 mm	0.451-0.452 in
.45	11.6 mm	0.458 in
.454	11.53 mm	0.454 in
.458, .46	11.6 mm	0.458 in
.475, .480	12 mm	0.475 in
.50	12.7 mm	0.50 in
.50	12.95 mm	0.510 in
.68	17.5 mm	0.683-0.696 in	Typically .689 Caliber, not called 17.5mm )