The '84 and '87 with the wide spur hammers will also likely have a different, thinner, lighter firing pin, mated to a much longer, softer firing pin spring, and will also have a lighter-weight hammer spring. The best I can judge it on my own guns, the stock factory hammer springs in the early wide-hammer pre-B's are around 15 lbs. This yields a much lighter double action than what you'd find on a current-production CZ or on a later early-90's pre-b. The hammer hook cuts and the arching radius on the early wide hammers also gives a cleaner, lighter single-action break with almost no camming. And the double action does not "stack" or get heavier at the end of its travel right before the sear drops, the way it typically does with the later, thinner, lighter pre B spur hammers like on your '91. Putting a bone stock '84 and '91 in each hand and dry firing them in DA should reveal the "real" differences in the action parts, that are more than just minor subtle aesthetics.......assuming they both still have their factory parts and springs.
Most of my pre-1989 CZ 75 pre B's, in bone-stock configuration, feel like they already had a trip to the custom shop because of those features. They have great action in stock trim, and need nothing, they're great shooters as-is (unless you wanted to upgrade the sights). If you want to buy a vintage CZ, leave it totally stock, and just enjoy its greatness, it's really hard to beat an early pre-1989 wide-hammer CZ 75. I even like the glossier feel and look of the very fragile early black enamel paint on those guns. Just don't chip them or expect them to hold up to any holster wear LOL!
But be careful, I don't know of any source to get those early pre-B thin firing pins, OR the early long soft firing pin springs. The pre-b firing pins and reduced-power firing pin springs sold by CZ custom and Cajun will not fit the early wide-hammer CZ pre-b's such as your 1984. If you break a firing pin, or try cutting down a firing pin spring to experiment with, you're beat. And no one makes an aftermarket "extended" firing pin that I'm aware of for the wide-hammer early pre-b's either. So they're not an ideal candidate to buy for a bunch of customizing and action upgrade work, since the standard firing pin length will keep you from going much lighter on the stock hammer spring.....
Cheers and thanks for the great post. Can't get enough of the ol' pre B's. I love mine. I even have an early factory "gloss blued" 1983 that has started to turn a sweet purplish hue with age, probably due to a less-than-ideal balance of chemicals in the bluing tanks back when it was made. She looks super vintage and feels sooooo silky......My '82 is almost identical, even the purplish bluing....
1983 Pre B blued
