p0838
Reloader Fred covered the upgrades nicely in his response on page one. Extractor, spring, guide rod and barrel bushing. My problem, as well as the roughly 150 other members of my So Cal Sheriff's office, was with the 59 (the 39 had the identical parts). They were ordered directly thru the department from Smith in 1974. Reliability was a major issue from the onset. My particular weapon began to gouge the guide rod after only a few magazines. As things worsened, the friction would cause the slide to short cycle. Hot rounds would function, but added to the damage. Someone please correct me if I am wrong, but as I recall (from thirty plus years ago) the initial issue, mine included, had an alloy aluminum guide rod and the fix was a steel one? Others had extractor problems, leaving the spent round in the chamber. The gun was very new then and Smith didn't have any fixes yet. Hence, most if not all were sold, as I did mine. Reliability was first and foremost for us in any firearm, on or off duty. While I never owned one again, I have heard the fixes were good enough to make the gun far more reliable. The second generation was prompted, I believe, by the poor rep of the first series.
There are other mitigating factors in the first generation that were not necessarily the fault of the weapon. Ammunition at the time was not nearly of the quality of today's offerings. Anyone remember High Vel (?), by Lee Jurras? He manufactured the hottest ammo available but quality control finished his run. Also, some of it was far to hot for the guns at the time. Pressures were far beyond today's standards and subsequently hard on guns. I believe while the 39/59 were a great start, they needed and received improvement over time, as did the ammunition.