Lead Density (aprox.)
11.352	g/cm3
0.400423	oz/cm3
6.56176	oz/in3
0.41011	llb/in3
2.43837	in3/llb

Bore size is defined as the number of lead balls of a given diameter that can be made from one pound of lead.
For shotguns, numeric bore sizes above 32 bore (i.e. smaller diameter) are not generally used.

Volume of 1 pound of lead is (about) 2.43837 in³

Volume of a sphere is (4/3)PiR³

Boresize		Volume (in3) per ball		R3 (inches3)		R(adius) (inches)		Bore Diameter (inches)
1	bore	2.438369		0.582118		0.834969		1.670
2	bore	1.219185		0.291059		0.662715		1.325
3	bore	0.812790		0.194039		0.578935		1.158
4	bore	0.609592		0.145530		0.525998		1.052
5	bore	0.487674		0.116424		0.488293		0.977
6	bore	0.406395		0.097020		0.459501		0.919
7	bore	0.348338		0.083160		0.436487		0.873
8	bore	0.304796		0.072765		0.417485		0.835
9	bore	0.270930		0.064680		0.401411		0.803
10	bore	0.243837		0.058212		0.387558		0.775
11	bore	0.221670		0.052920		0.375439		0.751
12	bore	0.203197		0.048510		0.364706		0.729
13	bore	0.187567		0.044778		0.355104		0.710
14	bore	0.174169		0.041580		0.346440		0.693
15	bore	0.162558		0.038808		0.338563		0.677
16	bore	0.152398		0.036382		0.331358		0.663
17	bore	0.143433		0.034242		0.324729		0.650
18	bore	0.135465		0.032340		0.318600		0.637
19	bore	0.128335		0.030638		0.312910		0.626
20	bore	0.121918		0.029106		0.307605		0.615
21	bore	0.116113		0.027720		0.302643		0.605
22	bore	0.110835		0.026460		0.297986		0.596
23	bore	0.106016		0.025309		0.293603		0.587
24	bore	0.101599		0.024255		0.289468		0.579
25	bore	0.097535		0.023285		0.285555		0.571
26	bore	0.093783		0.022389		0.281846		0.564
27	bore	0.090310		0.021560		0.278323		0.557
28	bore	0.087085		0.020790		0.274969		0.550
29	bore	0.084082		0.020073		0.271772		0.543
30	bore	0.081279		0.019404		0.268718		0.537
31	bore	0.078657		0.018778		0.265797		0.532
32	bore	0.076199		0.018191		0.262999		0.526
33	bore	0.073890		0.017640		0.260315		0.521
34	bore	0.071717		0.017121		0.257737		0.515
35	bore	0.069668		0.016632		0.255259		0.510
36	bore	0.067732		0.016170		0.252873		0.506
37	bore	0.065902		0.015733		0.250574		0.501
38	bore	0.064168		0.015319		0.248357		0.497
39	bore	0.062522		0.014926		0.246216		0.492
40	bore	0.060959		0.014553		0.244146		0.488
41	bore	0.059472		0.014198		0.242145		0.484
42	bore	0.058056		0.013860		0.240208		0.480
43	bore	0.056706		0.013538		0.238331		0.477
44	bore	0.055417		0.013230		0.236512		0.473
45	bore	0.054186		0.012936		0.234747		0.469
46	bore	0.053008		0.012655		0.233033		0.466
47	bore	0.051880		0.012385		0.231369		0.463
48	bore	0.050799		0.012127		0.229751		0.459
49	bore	0.049763		0.011880		0.228177		0.456
50	bore	0.048767		0.011642		0.226645		0.453
51	bore	0.047811		0.011414		0.225154		0.450
52	bore	0.046892		0.011195		0.223702		0.447
53	bore	0.046007		0.010983		0.222286		0.445
54	bore	0.045155		0.010780		0.220905		0.442
55	bore	0.044334		0.010584		0.219558		0.439
56	bore	0.043542		0.010395		0.218243		0.436
57	bore	0.042778		0.010213		0.216960		0.434
58	bore	0.042041		0.010037		0.215705		0.431
59	bore	0.041328		0.009866		0.214480		0.429
60	bore	0.040639		0.009702		0.213282		0.427
61	bore	0.039973		0.009543		0.212110		0.424
62	bore	0.039329		0.009389		0.210963		0.422
63	bore	0.038704		0.009240		0.209841		0.420
64	bore	0.038100		0.009096		0.208742		0.417
65	bore	0.037513		0.008956		0.207666		0.415
66	bore	0.036945		0.008820		0.206612		0.413
67	bore	0.036394		0.008688		0.205579		0.411
68	bore	0.035858		0.008561		0.204566		0.409
69	bore	0.035339		0.008436		0.203573		0.407
70	bore	0.034834		0.008316		0.202599		0.405
71	bore	0.034343		0.008199		0.201644		0.403
72	bore	0.033866		0.008085		0.200706		0.401
73	bore	0.033402		0.007974		0.199785		0.400
74	bore	0.032951		0.007866		0.198881		0.3978
75	bore	0.032512		0.007762		0.197993		0.3960
76	bore	0.032084		0.007659		0.197121		0.3942
77	bore	0.031667		0.007560		0.196264		0.3925
78	bore	0.031261		0.007463		0.195421		0.3908
79	bore	0.030865		0.007369		0.194593		0.3892
80	bore	0.030480		0.007276		0.193779		0.3876
81	bore	0.030103		0.007187		0.192978		0.3860
82	bore	0.029736		0.007099		0.192191		0.3844
83	bore	0.029378		0.007013		0.191416		0.3828
84	bore	0.029028		0.006930		0.190653		0.3813
85	bore	0.028687		0.006848		0.189903		0.3798
86	bore	0.028353		0.006769		0.189164		0.3783
87	bore	0.028027		0.006691		0.188436		0.3769
88	bore	0.027709		0.006615		0.187720		0.3754
89	bore	0.027397		0.006541		0.187014		0.3740
90	bore	0.027093		0.006468		0.186319		0.3726
91	bore	0.026795		0.006397		0.185634		0.3713
92	bore	0.026504		0.006327		0.184959		0.3699
93	bore	0.026219		0.006259		0.184293		0.3686
94	bore	0.025940		0.006193		0.183637		0.3673
95	bore	0.025667		0.006128		0.182991		0.3660
96	bore	0.025400		0.006064		0.182353		0.3647
97	bore	0.025138		0.006001		0.181724		0.3634
98	bore	0.024881		0.005940		0.181104		0.3622
99	bore	0.024630		0.005880		0.180492		0.3610
100	bore	0.024384		0.005821		0.179889		0.3598

Chamber sizes - Gun Trade - 1906