Need help and advice with my 9mm load for my M&P9.

[The ROC]

I've done alot research on the 9mm with 147 gr and Titegroup but my numbers are nowhere near what I've read.

My equipment:

- Located in Ontario, Canada (elevation a factor, if any?)

- Shooting Chrony (placed about 5 ft. from the muzzle of my M&P9)

- M&P9

- Mixed brass

- Federal 100 primers

- Titegroup (digital scale to confirm powder charge)

- Frontier 9mm 147gr. CMJ FN

- OAL is 1.130" (+/- 0.010")with a digital caliper

- No crimp, enought just to eliminated the belled mouth.

Results (5 shot average):

- 3.2gr @ 423 fps average

- 3.3gr @ 440 fps average

- 3.4gr @ 468 fps average

- 3.5gr @ 481 fps average

- 3.6gr @ 620 fps average

I want to a PF of 140 (up coming L3 match) which means I have to push 950 fps and no less the 900 fps MAX.

What do you suggest to help bump up the velocity... more powder (is it safe at current OAL) and/or shorten the OAL to 1.100" - 1.120".

Thanks for the help, have 2 weekends left to test my next batch of reloads.

Edited June 12, 2010 by The ROC

[Cy Soto]

I am willing to bet that your issue is that the muzzle of your pistol is too close to your chronograph. The erroneous readings you are getting are caused by the blast from the muzzle. Move your chronograph back to 10 to 12 feet and test your loads again.

Edited June 12, 2010 by Cy Soto

[TAP]

It's always good to check your chrony with a control round too.

[The ROC]

Forgot to mention that the loads listed above do cycle the slide with no FTF or FTE or stove pipe. The brass is falling about 2 - 3 feet at my 4 - 5 o-clock.

Could very well be that the chrony at 5 - 6ft is too close and the muzzle blast is causing the wrong readings.

Edited June 12, 2010 by The ROC

[G-ManBart]

Yep, you're too close and some particles are getting to the first sensor before the bullet so it tricks the chrono into thinking it takes the bullet longer to get to the back sensor. I use 5 steps which, for me, is slightly less than 15ft. R,

[gng4life]

Yeah, must be the case. On my M&P 9P, even with a reduced spring, I can't get loads that slow to cycle the slide. I think the lowest velocity I have seen to cycle my slide with an 11 lb spring (15 lb is factory) is in the upper 700's (fps) and that wasn't very reliable. Those readings have to be false. Let us know what happens when you move it back.

FYI...The manuals for the Shooting Chrony states:

"Distance of Chrony unit from muzzle: Air gun, .22 Rim fire => 3FT; Bow & Arrow =>4FT; Shot gun =>5FT; .30-30=>8FT; Large rifle=>10FT to 15FT; the bigger blast, the longer distance. "

I use to have one of these before I purchased my PACT chrono/timer unit and it was a decent little unit and worked great. I always set mine up at about 10-12'.

Edited June 12, 2010 by gng4life

[Lonnie]

I have a Shooting Chrony and have definitely had similar results if the chronograph is too close. I've settled on 12' from the muzzle. Lighting and angle of the sun can also affect readings.

[The ROC]

Thanks everyone for your help. Made up afew more test load and heading to the range tomorrow. This time not so close to the chrony.

[Darrell]

Put the Chrono 15 feet from the muzzle, 3.6 gr of T.G with a 124 gives me a 132 PF.

[The ROC]

Yup, turns out that the chrony was too close. This time I put it out to 12ft and here are my results:

7rds:

- 3.4gr @ 889fps average = 131 PF

- 3.7gr @ 951fps average = 140 PF

- 3.9gr @ 971fps average = 143 PF

Thanks for all your help.

[Bacon]

I put a target in front of my chrono to stop the powder from making it to the sensor before the bullet.

[TonyT]

3.4 gr. Titegroup with a 147 gr. FMJ gives me a tad over 900 fps with the chrono ca 12 ft from the muzzle.