As was mentioned earlier, you're gripping too low. This shows well in the first picture, not so well in the second. You want the meat of the web of your shooting hand to almost be rolling over the top of the frame knuckle. You will think it'll get pinched between the frame and the hammer during the trigger pull. If you are thinking that then you have gripped it high enough. This will actually provide you more leverage for a consistent trigger pull too.

With a wheelgun I lock down my shooting thumb with my support thumb. I shoot it the same way whether I am shooting right or left handed. With my auto jammers I tend to relax the thumbs and point them forward.

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