General Ball Dimensions & Tolerances
Ball Size | |||
MILLIMETERS TO INCHES | |||
MM | INCHES | MM | INCHES |
0.50 | 0.0196850 | 18.50 | 0.7283450 |
1.00 | 0.0393700 | 19.00 | 0.7480300 |
1.50 | 0.0590550 | 19.50 | 0.7677150 |
2.00 | 0.0787400 | 20.00 | 0.7874000 |
2.50 | 0.0984250 | 20.50 | 0.8070850 |
3.00 | 0.1181100 | 21.00 | 0.8267700 |
3.50 | 0.1377950 | 21.50 | 0.8464550 |
4.00 | 0.1574800 | 22.00 | 0.8661400 |
4.50 | 0.1771650 | 22.50 | 0.8858250 |
5.00 | 0.1968500 | 23.00 | 0.9055100 |
5.50 | 0.2165350 | 23.50 | 0.9251950 |
6.00 | 0.2362200 | 24.00 | 0.9448800 |
6.50 | 0.2559050 | 24.50 | 0.9645650 |
7.00 | 0.2755900 | 25.00 | 0.9842500 |
7.50 | 0.2952750 | 25.50 | 1.0039350 |
8.00 | 0.3149600 | 26.00 | 1.0236200 |
8.50 | 0.3346450 | 26.50 | 1.0433050 |
9.00 | 0.3543300 | 27.00 | 1.0629900 |
9.50 | 0.3740150 | 27.50 | 1.0826750 |
10.00 | 0.3937000 | 28.00 | 1.1023600 |
10.50 | 0.4133850 | 28.50 | 1.1220450 |
11.00 | 0.4330700 | 29.00 | 1.1417300 |
11.50 | 0.4527550 | 29.50 | 1.1614150 |
12.00 | 0.4724400 | 30.00 | 1.1811000 |
12.50 | 0.4921250 | 30.50 | 1.2007850 |
13.00 | 0.5118100 | 31.00 | 1.2204700 |
13.50 | 0.5314950 | 31.50 | 1.2401550 |
14.00 | 0.5511800 | 32.00 | 1.2598400 |
13.00 | 0.5118100 | 32.50 | 1.2795250 |
14.00 | 0.5511800 | 33.00 | 1.2992100 |
14.50 | 0.5708650 | 33.50 | 1.3188950 |
15.00 | 0.5905500 | 34.00 | 1.3385800 |
15.50 | 0.6102350 | 34.50 | 1.3582650 |
16.00 | 0.6299200 | 35.00 | 1.3779500 |
16.50 | 0.6496050 | 35.50 | 1.3976350 |
17.00 | 0.6692900 | 36.00 | 1.4173200 |
17.50 | 0.6889750 | 36.50 | 1.4370050 |
18.00 | 0.7086600 | 37.00 | 1.4566900 |
Ball Size | ||
INCHES TO MILLIMETERS | ||
INCHES | DECIMAL | MILLIMETERS |
1/32 | 0.03125 | 0.79375 |
3/64 | 0.04688 | 1.19063 |
1/16 | 0.06250 | 1.58750 |
5/64 | 0.07813 | 1.98438 |
3/32 | 0.09375 | 2.38125 |
1/8 | 0.12500 | 3.17500 |
5/32 | 0.15625 | 3.96875 |
3/16 | 0.18750 | 4.76250 |
7/32 | 0.21875 | 5.55625 |
¼ | 0.25000 | 6.35000 |
9/32 | 0.28125 | 7.14375 |
5/16 | 0.31250 | 7.93750 |
11/32 | 0.34375 | 8.73125 |
3/8 | 0.37500 | 9.52500 |
13/32 | 0.40625 | 10.31875 |
7/16 | 0.43750 | 11.11250 |
15/32 | 0.46875 | 11.90625 |
½ | 0.50000 | 12.70000 |
17/32 | 0.53125 | 13.49375 |
9/16 | 0.56250 | 14.28750 |
5/8 | 0.62500 | 15.87500 |
11/16 | 0.68750 | 17.46250 |
¾ | 0.75000 | 19.05000 |
13/16 | 0.81250 | 20.63750 |
7/8 | 0.87500 | 22.22500 |
1 | 1.00000 | 25.40000 |
1 1/16 | 1.06300 | 27.00020 |
1 1/8 | 1.12500 | 28.57500 |
1 3/16 | 1.18750 | 30.16250 |
1 ¼ | 1.25000 | 31.75000 |
1 5/16 | 1.31250 | 33.33750 |
1 3/8 | 1.37500 | 34.92500 |
1 7/16 | 1.43750 | 36.51250 |
1 ½ | 1.50000 | 38.10000 |
1 5/8 | 1.62500 | 41.27500 |
1 ¾ | 1.75000 | 44.45000 |
1 7/8 | 1.87500 | 47.62500 |
2 | 2.00000 | 50.80000 |
Grade Tolerances | Semi-Precision Balls |
Grade | Tolerance (inches) |
100 | ± .0001 |
200 | ± .0002 |
500 | ± .0005 |
1000 | ± .001 |
2000 | ± .002 |
Grade Tolerances | Precision Balls |
Grade | Tolerance (inches) |
3 | ± .000003 |
5 | ± .000005 |
10 | ± .000010 |
25 | ± .000025 |
50 | ± .000050 |
Number of Balls per Pound (approx.) | ||||||||||
Size | Size | |||||||||
Inches | Decimal | 302ss | 316ss | 420ss | 430ss | 440ss | Chrome | Carbon | Brass | Aluminum |
1/32 | 0.03125 | 218,819 | 217,299 | 223,508 | 225,116 | 227,571 | 221,138 | 220,360 | 204,517 | 625,821 |
1/16 | 0.06250 | 27,352 | 27,162 | 27,938 | 28,139 | 28,446 | 27,642 | 27,545 | 25,565 | 78,228 |
3/32 | 0.09375 | 8,104 | 8,048 | 8,278 | 8,338 | 8,429 | 8,190 | 8,161 | 7,575 | 23,179 |
1/8 | 0.12500 | 3,419 | 3,395 | 3,492 | 3,517 | 3,556 | 3,455 | 3,443 | 3,196 | 9,778 |
5/32 | 0.15625 | 1,751 | 1,738 | 1,788 | 1,801 | 1,821 | 1,769 | 1,763 | 1,636 | 5,007 |
3/16 | 0.18750 | 1,013 | 1,006 | 1,035 | 1,042 | 1,054 | 1,024 | 1,020 | 947 | 2,897 |
7/32 | 0.21875 | 638 | 634 | 652 | 656 | 663 | 645 | 642 | 596 | 1,825 |
1/4" | 0.25000 | 427 | 424 | 437 | 440 | 444 | 432 | 430 | 399 | 1,222 |
9/32 | 0.28125 | 300 | 298 | 307 | 309 | 312 | 303 | 302 | 281 | 858 |
5/16 | 0.31250 | 219 | 217 | 224 | 225 | 228 | 221 | 220 | 205 | 626 |
11/32 | 0.34375 | 164 | 163 | 168 | 169 | 171 | 166 | 166 | 154 | 470 |
3/8" | 0.37500 | 127 | 126 | 129 | 130 | 132 | 128 | 128 | 118 | 362 |
7/16 | 0.43750 | 80 | 79 | 81 | 82 | 83 | 81 | 80 | 75 | 228 |
Inches | Decimal | 302ss | 316ss | 420ss | 430ss | 440ss | Chrome | Carbon | Brass | Aluminum |
1/2 | 0.50000 | 53.4 | 53.1 | 54.6 | 55.0 | 55.6 | 54.0 | 53.8 | 49.9 | 152.8 |
17/32 | 0.53125 | 44.5 | 44.2 | 45.5 | 45.8 | 46.3 | 45.0 | 44.9 | 41.6 | 127.4 |
9/16 | 0.56250 | 37.5 | 37.3 | 38.3 | 38.6 | 39.0 | 37.9 | 37.8 | 35.1 | 107.3 |
5/8 | 0.62500 | 27.4 | 27.2 | 27.9 | 28.1 | 28.4 | 27.6 | 27.5 | 25.6 | 78.2 |
11/16 | 0.68750 | 20.6 | 20.4 | 21.0 | 21.1 | 21.4 | 20.8 | 20.7 | 19.2 | 58.8 |
3/4 | 0.75000 | 15.8 | 15.7 | 16.2 | 16.3 | 16.5 | 16.0 | 15.9 | 14.8 | 45.3 |
7/8 | 0.87500 | 10.0 | 9.9 | 10.2 | 10.3 | 10.4 | 10.1 | 10.0 | 9.3 | 28.5 |
Inches | Decimal | 302ss | 316ss | 420ss | 430ss | 440ss | Chrome | Carbon | Brass | Aluminum |
1 | 1.00000 | 6.68 | 6.63 | 6.82 | 6.87 | 6.94 | 6.75 | 6.72 | 6.24 | 19.10 |
1-1/16 | 1.06250 | 5.57 | 5.53 | 5.69 | 5.73 | 5.79 | 5.63 | 5.61 | 5.20 | 15.92 |
1-1/8 | 1.12500 | 4.69 | 4.66 | 4.79 | 4.83 | 4.88 | 4.74 | 4.72 | 4.38 | 13.41 |
1-1/4 | 1.25000 | 3.42 | 3.40 | 3.49 | 3.52 | 3.56 | 3.46 | 3.44 | 3.20 | 9.78 |
1-5/16 | 1.31250 | 2.95 | 2.93 | 3.02 | 3.04 | 3.07 | 2.98 | 2.97 | 2.76 | 8.45 |
1-3/8 | 1.37500 | 2.57 | 2.55 | 2.62 | 2.64 | 2.67 | 2.60 | 2.59 | 2.40 | 7.35 |
1-1/2 | 1.50000 | 1.98 | 1.96 | 2.02 | 2.04 | 2.06 | 2.00 | 1.99 | 1.85 | 5.66 |
1-3/4 | 1.75000 | 1.25 | 1.24 | 1.27 | 1.28 | 1.30 | 1.26 | 1.25 | 1.16 | 3.56 |
Inches | Decimal | 302ss | 316ss | 420ss | 430ss | 440ss | Chrome | Carbon | Brass | Aluminum |
2 | 2.00000 | 0.835 | 0.829 | 0.853 | 0.859 | 0.868 | 0.844 | 0.841 | 0.780 | 2.387 |
2-1/4 | 2.25000 | 0.586 | 0.582 | 0.599 | 0.603 | 0.610 | 0.592 | 0.590 | 0.548 | 1.677 |
2-1/2 | 2.50000 | 0.427 | 0.424 | 0.437 | 0.440 | 0.444 | 0.432 | 0.430 | 0.399 | 1.222 |
2-3/4 | 2.75000 | 0.321 | 0.319 | 0.328 | 0.330 | 0.334 | 0.325 | 0.323 | 0.300 | 0.918 |
3 | 3.00000 | 0.247 | 0.246 | 0.253 | 0.254 | 0.257 | 0.250 | 0.249 | 0.231 | 0.707 |