Len is right on the money with regard to yardage. Statistically as you probably know most armed encounters happen at seven yards or less. As far as an older snub goes, no problem with that either. The new breed of lightweight snubbies are of the "carry a lot', "shoot little" variety, in my opinion, because for the most part they just aren't fun to shoot for the majority of people who own them, at least from what I have observed.
Personally I have never cared much for any of the "J" frame Smiths, but back in the day, a Chief's was THE police back-up weapon and plainclothes carry weapon. It's fans were legion, and although I suppose by today's standards a traditionally manufactured Model 36 or Model 60 represents older technology, it is very good technology, indeed. One of these older style snubbies will definitely get you through the night.
My personal choice has always been the Detective Special. At the sunset of Colt's double action revolver manufacturig in the middle 90's, it came out with the Detective Special II and finally a stainless .357 Magnum version. In hindsight, I wish I would have picked up examples of either or both. Today, my primary carry weapon is a Ruger SP101 DAO. I don't mind the weight, and find that I can control that revolver fairly well, and the "feel" is quite reminiscent of a Detective Special (my DS is semi-retired now as are all of my Colt Revolvers).
Now what I am about to say now, may evoke some yikes and cripes from our distinguished forum of dedicated pistoleros, but in the past few years I have heeded the advice of Massad Ayoob when it comes to defensive revolvers. Now, whether you love him or hate him, his experience as an expert witness (usually for the defense) in shooting incident trials, has given him a unique perspective on the legal system and how it relates to The Few, The Proud (I don't mean Marines here, but lawfully armed private citizens) who find themselves enmeshed in draconian gun laws and in courts presided over by hopolophobic judges, with overzealous prosecutors who think the Second Amendment is about duck hunting, and juries whose concept of firearms comes from watching too many cop show reruns on cable. Mas advocates that any personal defense revolver be converted to DAO if it isn't already in that mode. His reasoning is that there have been just way too many prosecuters who have alleged that the evil perpetrator (translated: the lawfully armed citizen, who in fear of his or her life, discharged their lawfully owned weapon against a real evil perpetrator) cocked the weapon and the resulting single action "hair trigger" allowed the weapon to discharge and thus, the shooter displayed reckless and wanton disregard for human life. Having a DAO revolver eliminates one more arguments for the prosecution. Since you have already indicated that you will probably have the hammer spur ground down, I'd say go ahead and have the revolver converted to DAO at the same time, as it still might be possible to thumb cock the revolver even with the spur ground down.
Key to developing proficiency with a snubbie is to practice, and to practice with the loads that you will use in the real world. Personally I have come to like the Remington 125 gr +P .38 Spec. because for me it is controllable and accurate. Speer has a new load for short barreled revolvers: a 135 gr +P .38 Spec., I tried a box of those in my Ruger last Monday up in Manchester, and found them not to be as accurate as the Remingtons in my particular gun. Yes, I have fired .357s in my Ruger, but have better controllability with the +P 38's.
With regard to +P's in older Chief's, my understanding is that they will take it provided they were made after 1958, but it is a good idea to have a gunsmith (preferably a S&W trained armorer) check it out every thousand rounds or so for frame stretching and forcing cone erosion. Colt, I believe always said check the DS at 3000 rounds if firing +P's.
Now folks today, have their Kahrs and mini-Glocks (at least the folks who don't live in Massachusetts [lol]) chopped down .45's and such. I have nothing against these guns at all, but as I get older I get more retro, and I really do appreciate the simplicity and everyday realiability of the revolver. I think getting an older snubbie, in good shape, at a fair price is a great way to go.
Regards,
Mark