Seriously, you're worried about the lock in a 22 caliber 617? I wouldn't bother, the only way the lock in that gun will move is if you use the key or drop the gun on concrete.
BTW, I have a 6 1/2 inch 610 and a 4 inch 620, both with more than 2000 rounds downrange, and the only time the lock has engaged on either is when I've used the key.
I've also spent a bit of time tuning both guns and the lock has zero effect on trigger pull or primer ignition. Currently the 620 is tuned to 8 lbs. in double action and it'll shoot accurately with every ammo I've been able to find for it, WWB is 100%, Federal is 100%, Speer Lawman is 100%, and Remington is 100%. As for the 610, the Pachmayr Decelerator currently mounted on it will cause the mainspring to hit the grip screw with the trigger set to anything under 9 lbs, one of these days I'll get the 500 Magnum monogrip for it and see how light I can take it. However, at 9 lbs. it's proven to be 100% reliable with the same mix of brands as the 620.
BTW, I also have a 6 inch 617 no dash that I've tuned to a 9 lbs. 3 ounce DA trigger. However, the only ammo I've used in the 617 is Winchester Xpert HV and Federal Bulk. As in my other revolvers, ignition has proven to be 100% reliable as long as I keep the cylinder clean. With the Winchester ammo the cylinder will start to get fouled after 50-70 rounds and it becomes difficult to fully seat each round. When that happens any round that isn't fully seated will misfire on the first try. If the Winchester wasn't so darned accurate in the 617 I'd stop shooting it, however it'll goup 35% better than the Federal so I keep using it when I want shoot for precision.
Sum it up and IMO you really don't have to be concerned about the lock, there just isn't enough recoil with the 617 to cause any issues. You've also purchased a VERY fine revolver capable of surprizing accuracy. Have fun with it and if you get really curious about how accurate it can be I'd suggest mounting a 2X scope on it.