Olds Register photo guide – Los Angeles

Question 12: Bore mark

For the first few years of production in 1930’s Olds offered different bore sizes on some models. This only applies to trumpets and cornets with serial numbers less than 7000. The bore mark is on the left side of valve casing just below where the bell crosses. It is on the opposite side of the casing from the serial number. The stamp is not as pronounced as the serial number.

M Bore (medium)

SYM Bore (Symphony)

LM Bore (Large Medium)

LLM Bore (Large large medium)