Terry: I recently fully replaced a spring rail, rabbeting out the ledge and taking a pattern of holes from the original (1872 Sty ur). The springs I used were originally from a set of springs provided for the Renner back action replacement kit. The originals were .025 and the replacements were .029. There is no problem with this if regulated properly; the regulation is easy--just massage the springs back starting at the coil end if they are too strong, and forward if too weak. At first I was amazed at what they added to the touch weight before I weakened them. But you should not have to worry if you are within such tolerances as you describe. PR-J
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