Mike, that stickiness in the DA trigger pull suggests that you've got some old dried out crusty lube in the gun or that it simply hasn't been shot a lot over it's life. Generally a correctly clean and lubricated S&W action will smoothen up nicely from all the parts wearing together. But grit or lumps if dried up lube can make the parts all stick.
If you don't feel confident enough to pop the side cover after watching the usual videos then a good first step would be a good flushing of the action with something like brake cleaner, Gun Scrubber or, my favourite, Ed's Red. This involves removing the grips so you have a clear shot then spraying the cleaner VERY liberally into the action then working the action to clear and dissolve any crud.
If using the degreasing cleaner like brake cleaner or Gun Scrubber you'll want to mix follow the cleaning with a hose down with a spray gun oil. If you squirt the oil into the action while it's still well soaked with the cleaner then the two will mix and the excess oil SHOULD drain out and when the solvent dries you'll be left with a light coating of oil over all the parts. Or if you have compressed air a few good shots up past the main spring and down through the cocked hammer opening will also clear out the excess oil.
I prefer the Ed's Red since it automatically drains most of itself out along with the gunk then dries to a light film of ATF oil to protect and lubricate. A simple ketchup or similar squirt bottle does a great job of holding enough to flush out the action.
Wear Nitrile gloves for all of this since all these solvents are hard on your skin and to some extent leech through and into the blood stream. Not a good thing at all. And you need to work the action in DA while soaked down and dripping to work the stuff clean. And if using the compressed air to blast out excess oil then wear an old shirt and eye protection. The stuff will come out EVERYWHERE! ! ! !
There is not doubt that your gun has SOMETHING inside the action. All my S&W's have triggers that feel like a fresh caught fish on a wet cleaning board. And for those that haven't done such a think THAT IS SLICK! ! ! !
If the cylinder is stiff on the ejector and it's not at all bent then a good long soak in the Ed's Red is called for. In fact at that point making up enough that you can simply soak the whole pistol in the mix sitting in a suitable sized close fitting rectangular food saver is the way to go. In this case soak for 20 minutes then lift out and drain well, work the action, spin the cylinder, run the ejector. When it all stops dripping fast then dunk it and soak again for 20 minutes. Repeat this same dunk, drain, operate cycle a few times. Finally allow to drain fully and let it dry out.
If it's still less than silky smooth you'll need to make a judgement call on whether or not it's due to some grit that's trapped inside or if you feel it's simply the machining marks rubbing and catching. If it's machining marks the trigger should smoothen up over a few hundred trigger pulls. If it doesn't I'm going for the idea that there's some foreign junk stuck inside and you'll need to pop the side cover and/or detail strip the ejector and crane. It's your call if you take this on or if you take it to a smith.
