The powder you skipped over, Titegroup, is my standard powder for 180gr in .40 S&W. My goal is to load major power in .40 for USPSA, which means I just have to be sure MV is over 917. I use Precision Delta FMJ 180gr.


I had a SW40VE but sold it, and use a .40 HIPo. Based on my .40 experience, I suspect the pronounced vertical stringing in your groups is more associated with the Sigma trigger affecting the shooting than with the powder in the loads. In some load experimenting I did, varying the powder charge by up to half a grain still had the bullets shooting into the same group.


The most significant factor I found was a batch of soft plated bullets that turned coffee cup groups into serving platter patterns.

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