I have two older 6 shot 66s. I love 'em, extreme accuracy and decent triggers. The newer one is the new transfer bar action and it's very smooth, sweet trigger. It's a 4" gun and I have a 3" gun I bought not too long ago. I carry the 3" a lot IWB. I find it doesn't print through a loose T shirt like my Ruger .45 auto does a little. It's only a bit over 30 ounces, easy enough to carry all day IWB, though it's no titanium tracker. The older hammer block lockwork isn't as smooth DA and has a little rougher SA trigger, too, but it's usable and not a problem in off hand shooting. I would look for a newer transfer bar action gun, though, if you want a really slick trigger. The newer guns just keep getting better and better unlike some companies who seem to be deteriorating.
I bought both of my guns at gun shows used. The nickeled 4" is awesome, got it for $197 and it was in like new condition. The blued one has a bit of bluing/holster wear and had a timing problem which turned out to be an easy fix and I knew it wouldn't affect function, but figured I might could fix it. I used it to bargain the guy from $200 down to $180, brought it home, fiddled with it, fixed it. Guy just had the wrong screw in the forward frame position, the one that holds the cylinder crane in place. The too short screw was causing all kinds of cylinder crane slop and throwing it out of time. Put the screws back right and perfect!
Anyway, around here, these guns are pretty common at gun shows and they sell for pretty cheap, a LOT less than a worn out old M10 Smith will, and they're quality guns. I just check 'em thoroughly before purchase and if I deem it's worth the investment, I'll jump. You can't touch a M19 Smith around here for under $400 in any sort of shootable condition, and the M66 doesn't have the flat spot on the bottom of the forcing cone that often causes the Smiths to split after some wear. I also prefer the frame mounted floating firing pin to one mounted on the hammer. I've had a hammer mounted firing pin break on me before and have heard of others, Smith and Wessons, too. I've also heard of the spring in the floating firing pin breaking, but I suspect it's rare and in guns that are dry fired a lot. I've not seen it happen in a Taurus or Ruger, put it that way. But, that's not a big deal. It seems quite rare for a hammer mounted firing pin to snap and I don't dry fire without snap caps in any of my guns. The gun it happened to on me had a problem, burr or something, but a gunsmith fixed it.
Anyway, my 4" gun groups .38 wadcutter or its favorite .357 load into 1" at 25 yards, as good as I can shoot iron sights, and the 3" gun ain't too far behind that one. One thing I've come to expect with Taurus revolvers is impressive accuracy, but then, I only have three
so far.
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