I recently returned an MPX to SIG to have them figure out why it would throw bullets all over the place at 50 yards. It runs very well but the accuracy/precision has been frustrating to say the least. I tried suppressed and unsuppressed, two different optics, iron sights and at least four factory loads ranging from 115gr to 147gr. No combination would reliably hold a group so back it went. I got it back in a little over a week with a new barrel installed.
A couple of years back I started to work up a 147gr handload for suppressed shooting but the results were bad to very bad so I put the MPX on the back burner. It had me thinking that the Vortex optic was defective. Over the Christmas break I wanted to see what it would do with factory subsonic ammunition. I bought a few boxes of SIG 147gr FMJ with an advertised MV of 985 ft/sec and the results were so bad i.e. 12" or greater groups at 50 yards with bizarre "fliers" that I decided to contact SIG.
To be honest, I don't have much experience with subsonic 9mm so what is a reasonable expectation using factory ammunition at 50 yards? If you've handloaded subsonic ammunition, what have you achieved at 50 yards? SIG did ship the MPX back to me with a new barrel that shoots a lot better than the original barrel but still not much better than 6" to 8" (10 shots) at 50 yards using the SIG 147gr FMJ load. The included test target shows a 5-shot, approximately 3/4" group at 25 yards using 115gr ammunition. Are 9mm firearms and heavy for caliber subsonic loads a finicky proposition at 50 yards?
Thanks.
A couple of years back I started to work up a 147gr handload for suppressed shooting but the results were bad to very bad so I put the MPX on the back burner. It had me thinking that the Vortex optic was defective. Over the Christmas break I wanted to see what it would do with factory subsonic ammunition. I bought a few boxes of SIG 147gr FMJ with an advertised MV of 985 ft/sec and the results were so bad i.e. 12" or greater groups at 50 yards with bizarre "fliers" that I decided to contact SIG.
To be honest, I don't have much experience with subsonic 9mm so what is a reasonable expectation using factory ammunition at 50 yards? If you've handloaded subsonic ammunition, what have you achieved at 50 yards? SIG did ship the MPX back to me with a new barrel that shoots a lot better than the original barrel but still not much better than 6" to 8" (10 shots) at 50 yards using the SIG 147gr FMJ load. The included test target shows a 5-shot, approximately 3/4" group at 25 yards using 115gr ammunition. Are 9mm firearms and heavy for caliber subsonic loads a finicky proposition at 50 yards?
Thanks.
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