I purchased a new M&P40 compact last month. I've taken it to the range twice, shooting 150 rounds each time for a total break-in of 300 rounds. I've tried a variety of FMJ ammo, 50 rounds each of the following with NO malfunctions (nice!):

Winchester WB 165gr
Federal American Eagle 165gr
RWS 180gr
Remington UMC 180gr
PMC Bronze 180gr
Winchester Ranger 180gr

MP40C_ammo.jpg

This target photo is from my best effort so far ... a 3.25 inch group for 20 rounds (two mags worth) at 6.7 yards. I was alternating between the flush magazines and ones with the pinky extension. Gripping the pinky extension definitely feels more secure in my hands, but this "ordinary" shooter isn't good enough to detect a difference in accuracy with either type of magazine.

MP40C_w_Target.jpg

I'm very happy with my purchase so far. I plan to try some JHP rounds on my next range visit. I'll be surprised if my next range trip changes my opinion of this pistol.

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MP40FS,MP40C,MP22
NRA,ISRA

I've had my 40c for a few years now. Tried many types of ammo with only one that didn't function perfectly. Ironically, that was "Perfecta" from wal-mart. It failed to feed some 40% of the time. No Exaggeration! Nice shooting by the way.

I really like my 40c and my 9c. If you call customer service and ask they may send you the pinky extensions for free.

My 40 Compact has run everything reliably .. have not had a error in about 1350 rounds so far ..

I get 1 3/4 inch 10 shot groups at 30 feet .. If I do my part .. but not until I tried the large back strap did my groups get that tight .. using the medium and small back strap I was getting 3-5 inch 10 shot groups ..

So might suggest trying all of the back straps to see which you shoot the best with !!

I use 10 shot groups because it divides a box of 50 into 5 mags evenly ..

I bought the 40C new in 2015 been flawless

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Spin The Wheel

Yes, I took off the medium backstrap that came installed and put on the large. I've only fired rounds using the large backstrap, since it feels the most secure in my hand. The large seems more bulbous and fills my palm better. If S&W made an extra large, I would probably try that !

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MP40FS,MP40C,MP22
NRA,ISRA

Good to read that you folks with the M&PC are happy with it. While I don't really need another M&P with 3 already...I really am thinkin about a Compact 40 since that's my caliber of choice. I always look at it as just another one to hand down to the kids. Better to give guns to the kids than give it to the nursing home in the future. I just like physical assets to pass on...I guess...if I have to... just sayin