Library › Hardware › BBs: steel Ø4.5 mm (.177) and airsoft Ø6.0 mm

steel BB Ø4.5 (.177 cal)

Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

ball	steel BB
dia_mm	4.5
note	.177 cal

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From the full sheet

BBs: steel Ø4.5 mm (.177) and airsoft Ø6.0 mm: every size, notes, mating features and sources. What diameter is a BB and an airsoft BB?

Other sizes

airsoft BB Ø6.0 (5.95)