I've owned many Columbia Yellow Dot bleeders (and non-bleeders) during the 1970s through the 1990s. I'd say I probably thrown close to 200 of them, and drilled maybe another 200 for customers during my days drilling balls.
Know that the first digit in the serial number refers to the last digit of the year the ball was manufactured, the second digit was a letter that refers to the month. In the mid-late 70s, the letter sequence started with N, so your 7Q was made in March 1977. Bleeders made from 1990 on had second digits starting with A. This holds true with all Columbia balls made in San Antonio until the manufacturing facility was shut down last year.
Many of the balls made that year that really bled were manufactured from March through December. The Ps, Qs, Rs, Ss, Ts, (March through June) and the Xs and Ys (October and November) were probably the best made since the outside temperature was moderate and the balls were able to cure naturally. The balls manufactured in the extreme months July, August, September and December, January and February were probably undercured (due to cooler weather) or overcured (due to the extreme Texas heat) probably because the balls sat in warehouses with limited climate control. And that's provided they made balls with that same plastic material. There were batches that were made with the same formula as the white dots probably because of curing issues. Historically, bleeders were as brittle as crystal and cracked much easier than the resin balls made in the past 10 to 15 years.
The bleeders that were made during and after 1979 especially were stored in more climate controlled conditions because these balls were REAL good. But for some reason, the bleeders made after that were just not the same. Most of the Yellow Dots made from 1976 and 1979 did not bleed, probably due to the formula being petroleum based, which was the same period of time as the oil crisis, so the formula used was probably the white dot formula. There were batches of bleeders made during that time, but they were in limited supply and most likely made for bowlers on the PBA Tour.
I bowled 833 in the 1983 ABC Tournament, at that time, a tournament record using a Bleeder, but I can't recall what the serial number prefix was, but I can tell you it was made after 1989. Following that tournament, I donated the ball to the Bowling Museum/Hall of Fame because the few times I used that ball before and after that event, that ball was a virtual boat anchor anywhere else I bowled with it.
I hope this answers some questions about the Columbia Yellow Dots of the 1970s and 1980s. If my response is not very accurate, I would expect someone who has tremendous experience with these balls (from back in the day) to chime in and clear us up.
FRAN
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Fran Bax
A Member of the Buffalo and New York State Bowling Association Halls of Fame
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Edited on 8/11/2008 7:01 PM