ShotCrimp’s Guide: Shotgun Cartridges, by Calibre and Loading

Gauge or Number	Bore (F) “	Chamber ID Front (C) “	Chamber ID Rear (B) “	Chamber Length (E) “	Chamber Length mm*	Rim OD (A) “	Rim Recess Depth (D) “	Rim Radius (R) “	Nominal Load (Oz)	Nominal Load (Grams)	Wad Dia (Inches)
4	0.935	1.035	1.090	4.00	–	1.200	0.130	0.030	4	114	0.948
8	0.835	0.914	0.930	3.25	80	1.035	0.115	0.020	2	57	0.845
10	0.775	0.845	0.861	3.25	80	0.933	0.074	0.020	–	–	0.784
10	0.775	0.845	0.859	2.875	75	0.933	0.074	0.020	1.4375	41	0.784
10	0.775	0.845	–	2.625	65	0.933	0.074	0.020	1.3125	37	0.784
12	0.729	0.800	0.815	3.00	75	0.886	0.074	0.020	1.625	46	0.738
12	0.729	0.800	0.813	2.75	70	0.886	0.074	0.020	1.5	42.5	0.738
12	0.729	0.800	0.812	2.50	65	0.886	0.074	0.020	1.0625	30	0.738
12	0.729	0.800	–	2.00	50	0.886	0.074	0.020	0.875	25	0.738
14	0.693	0.763	0.775	2.560	65	0.847	0.068	0.020	–	–	0.702
16	0.662	0.732	0.745	2.75	70	0.815	0.062	0.020	1.125	32	0.671
16	0.662	0.732	0.744	2.560	65	0.815	0.062	0.020	0.9375	26.5	0.671
20	0.615	0.685	0.698	2.75	70	0.766	0.060	0.020	1.00	28.5	0.623
20	0.615	0.685	0.698	2.560	65	0.766	0.060	0.020	0.8125	23	0.623
24	0.579	0.649	0.661	2.50	65	0.728	0.060	0.020	–	–	0.587
28	0.550	0.614	0.626	2.50	65	0.688	0.060	0.020	0.5625	16	0.557
32	0.502	0.562	0.574	2.50	65	0.636	0.060	0.015	–	–	0.509
67	0.410	0.465	–	3.00	75	0.537	0.060	0.015	0.625	18	0.415
67	0.410	0.465	–	2.50	65	0.537	0.060	0.015	0.4375	12.5	0.415
67	0.410	0.465	0.475	2.00	50	0.537	0.060	0.015	0.3125	9	0.415
No 3	0.360	0.415	0.424	1.75	–	0.479	0.050	0.015	–	–	0.363

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