There are a few things to consider regarding the "Six" series.
First, they were more expensive to make than the GP-100s. Second, they were plenty strong to begin with. Gun writer and former Border Patrolman Skeeter Skelton said he knew of three Ruger Security-Sixes, each of which had in excess of 30,000 rounds of hot magnum rounds put through them. On the other hand, people with S&W 19s were experiencing noticeable frame warping after 2,000-3,000 magnum rounds. NRA writer C.E. Harris said he ruined a Model 19 after shooting 2,000 rounds of magnum ammo! The gun still shot and even was retimed, but after another thousand rounds or so, it became unusable.
Three, Ruger convinced a generation of shooters that one spring doing the work of two springs was an improvement. But is it? I've experienced dry firing many Security- and Speed-Sixes, and after a few hundred snaps the action improves dramatically. And spring changes make these guns even better. I don't think the GP- models have better actions, are more accurate and last longer than the "Six" series. In fact, the balance is far worse than the Security-Six or the S&W 686! After looking at one at my local gun store, I wouldn't have one. I'd opt for a used Security-Six or a new/used 686. Ruger overbuilt an already overbuilt gun, and for what purpose? Anyway, opinions will vary. Them's my views.
S&W 686 and Ruger's Security-Six. The 686 is far too heavy to lug
around in the field. Unfortunately, S&W chose to stop production of its
excellent Model 66.
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