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Discussion Starter #1
My SA 9mm 5" RO seems to lose zero 2 to 3" high on 20% of my shots at 25 yds. on benchrest. I have installed an EGW angle-bore thick-flange bushing and a FF3 3MOA red dot. When shooting normally I can get 3 holes touching, maybe one 1 inch away and one 2 to 3" high 11:00 to 2:00 on most groups. I know the 1" deviation is me because it can occur on any clock number. At times I get 2 distinct groups in 5 shots 2" apart at 12:00. Sometimes my 5 shots are in a 2 to 3" line at 12:00. I'm using 115 JHP, 4.1 TG, 1.120 COL and sorted brass by brand and times fired.

My range visits vary from good groups with 1 flyer high to all 5 high then another visit with the same loads back to zero with 1 high.

I've examined the barrel and slide lugs under 5X and see no anomalies. The edges are very clean and sharp exhibiting no galling or roughness. SA refit the slide and put in a new barrel at 600 rounds. I now have an added 500 rounds. I've checked the FF3 mount screw tightness after every session and both are very tight.

Any solutions, suggestions or comments are welcome. Thanks.
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