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Well, the M&P will feed light loads.

2823 Views 11 Replies 4 Participants Last post by  ledge
Loaded a unch of 180gr precision delta heads over 3.7gr of titegroup to a nominal overall length of 1.133 inches. Yes, I know it is longer than max cartridge length specifications, but I also wanted to see if the M&P would feed long loads.



Shot a practice USPSA match and went through about 100 rounds without a hitch.



A very soft, pleasant load. I have to get out with a chronograph to see if it actually makes minor power factor.
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raz-0 said:
Loaded a unch of 180gr precision delta heads over 3.7gr of titegroup to a nominal overall length of 1.133 inches. Yes, I know it is longer than max cartridge length specifications, but I also wanted to see if the M&P would feed long loads.



Shot a practice USPSA match and went through about 100 rounds without a hitch.



A very soft, pleasant load. I have to get out with a chronograph to see if it actually makes minor power factor.


I shot a 150 rounds today that were 1.165" OAL. Did this to reduce pressure do to the high ambient temperature. It did the trick. Pressure was reduced, accuracy returned, no problems feeding.
Ok, I have a word of caution regarding light loads.



Keep your magazines clean if you try them. They aggravate dirty magazine problems given the design of the mag body and follower.



I have to say that reuslts would indicate you should keep it to SAMMI OAL or less.
raz-0 said:
Ok, I have a word of caution regarding light loads.



Keep your magazines clean if you try them. They aggravate dirty magazine problems given the design of the mag body and follower.



I have to say that reuslts would indicate you should keep it to SAMMI OAL or less.


I prefer major loads. More noise, more smoke, more fun.
Well I got a chance to get out and chrono these loads.



The average velocity was 752.2 fps which yields about a 135.4 power factor. Standard deviation was 12.5 fps.



Based on messing around, leaving your ammo in direct sunlight on a hot day with tightgroup in it seems to make velocity drop.



I think I'll shorten them up a tad and call them minor unless the feel of them changes. If they do, I'll drop a tenth of a grain off of it and start the process all over.



Then it's time to work up a major load.
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good info, next season I'm switching to tightgroup.
Ok, correction. I had some sort of major brain fart that wedged itself in my head as fact.



1.133 inches isn't longer than SAAMI max, SAAMI max is 1.135. For some reason my brian thought it was 1.125.
raz-0 said:
1.133 inches isn't longer than SAAMI max, SAAMI max is 1.135. For some reason my brian thought it was 1.125.
I feel better now. I was trying to figure out why you had that for a spec, but everything I have says oal basically between 1.125 and 1.135. Over in the forums at brianenos.com, there are some people reloading 40's way over max oal. Not sure that I'm that brave yet, but it is being done. I'm not in any hurry to do that anyway, as I'm currently shooting major, and without a chrono, I don't plan on switching to production and cooking up some minor pf loads.
Ok, I shortened to 1.125 nominal, and it makes the round a little bit less mellow. Unfortunately not enough where I feel comfortable knocking the charge down to 3.6gr.



as for people loading way over max length in the enosverse, that's .40 out of a 1911, so you have more room to play with. Frankly after doing load research I'm almost of the opinion the standard USPSA loads for a 2011 or para shouldn't even be considered .40 S&W anymore.
raz-0 said:
Frankly after doing load research I'm almost of the opinion the standard USPSA loads for a 2011 or para shouldn't even be considered .40 S&W anymore.
Ok, this topic interests me. I've been loading strictly within specs, but am interested in the effects of changing the variables within reloading. I seated some bullets in some empty cases and found that 1.175 oal length rounds still fit in the magazine, feed and chamber. What is it that leads you to believe that the USPSA loads shouldn't be considered? Don't take me at all wrong, I'm not in any way doubting your findings. I'm just curious as to what leads you to this conclusion as a matter of education, not doubt.
Feel free to doubt. But I'll clarify my opinion.



First off, a lot of the para and 2011 guys load to 1.18 heck even 1.2 and change. These won't fit in the magazine for most guns chambered in .40. Not to mention that all the load data in the manuals is meaningless once you go to those dimensions. Most importantly, when you have someone who shoots one of these rounds causually say I put a 180gr head over 4.8 grains of titegroup and then doesn't give the OAL, you have really bad advice that could cause someone problems as the math is bad going form a safe longer load to shorter SAAMI specs for max OAL.



As for what will work in the M&P, 1.18 will only fit about 3 rounds in the magazine before they hang up from binding. A little over 1.18 and you only get two. Personally, after having 1.133 OAL rounds bind with a little bit of sand in the magazine, I doubt I'd trust 1.175 to feed while running and gunning. The M&P follower can tilt some, and I can just imagine the 15 round mags lozded to 10 might just allow the rounds to tilt some and bind up with those kind of minimal clearances.



Personally, I try to load as long as i can get away with as it is usually better for accuracy provided you don't go too far with it.



Feel free to doubt, share your experiences with what works for you. I'm just one guy and the more people that contribute detailed info, the better idea we will have what will work.



Those 1.175 rounds, how many you load in the magazine at start? What bullets (i'm using precision delta 180gr, which are a kind of funky profile)? Are you doing fast reloads that might jostle stuf inside, or are you casually shooting from the firing line?



Any of that stuff can make a difference in what will fail to function.
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raz-0 said:
Those 1.175 rounds, how many you load in the magazine at start?
Only a couple of rounds.

raz-0 said:
What bullets?
180g FMJ and 180 cast TC

raz-0 said:
Are you doing fast reloads that might jostle stuf inside, or are you casually shooting from the firing line?
I shoot IPSC, so when it counts , there will be movement.

raz-0 said:
Any of that stuff can make a difference in what will fail to function.
That is exactly the info I was looking for. I'm currently shooting Limited 10 Major, but might move to production. The info you've given me will help me to better explore my options for shooting minor pf. Thanks a lot.
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