Thanks to "Tracer" on CrossbowHunting for this:

Chart for Calculating Deer Weight in the Field
Measure all the way around the deers chest/belly/back just behind its front legs to get the girth. Print out the chart, use a soft tape, put them in a baggie to carry with you .

Chest/Girth (in.) Live Wt. Field-Dressed Lbs. Edible Meat

32 102 80 45

33 110 87 50

34 118 91 54

35 126 99 57

36 135 104 61

37 146 115 66

38 157 126 71

39 169 135 74

40 182 144 80

41 195 156 88

42 210 170 94

43 228 182 103

44 244 198 110

45 267 214 120

46 290 233 130

47 310 251 139

48 340 272 153

Source: Penn State Dept. of Animal Science and PA Game Commission
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