M & P question for SSS, Burwell or any guru

[RWF]

i have 2 M & P's on layaway with plans for a his and hers open M & P 9mm pistols. main question is the comp makers says a 11# reciol spring for for best results. but Dan for exsample says do not go below the factory spring wieght.

i have tried a 13# before but the seemed slow.

so what is the right answer?

[horseman]

I don't know the right answer. I run a #13 in my 40 pro and it is perfect. I tried really hard to make the 11 work in a 9mm 4.25 but it was too snappy for me. I just could not get used to it. Put a #13 in and good to go. The #11 did function OK. I would say try em and see what works for you. I am a C limited and SS shooter. I do shoot an #11 in SS. I seem to fine tune the feel I want with powder charge after I get in the ballpark with the spring.

[MGMorden]

All up to you, but I had failures to return to battery even with a 14# spring on my 9L. During actual firing it would happen about once every 40-50 shots. Took me forever to pin that down as the cause (for a long time I thought it was the "dead trigger" issue but it persisted even after going to the giant sear plunger setup). Not sure why as I know some people are running a lot lighter than that, but it bit me in the butt 1 too many times. Switched to the stock recoil spring/guide rod and it has gone nearly 1000 more rounds now with no issues.

Edited December 5, 2011 by MGMorden

[RWF]

this why i asked, 2 totally different answers. i never have had function issues no matter the spring #. somewhere in here i got a friend to post pictures of my limited gun. it has been lighten, but i plan to lighten these up more, but if i have to use a slide rider red dot i will most likely break even on the weight.

right now i am not using flat wire springs, and on my 13# spring was short compaired to 14. i told to the guy i get my springs from and said all the springs have the same # of coils. i may go back to tungsten and flat wire for these. unless he make something up for me.

[mcracco]

I have 13# springs in 3 M&P's: 9Pro, 9FS, and 40L. I shoot heavy bullets that just clear the 125K pf and have never had a problem with a slide not returning to battery. The same guns with the same loads with the factory 16# spring will not cycle reliably.

If you are shooting factory loads or higher velocity handloads leave the factory spring in.

[basman]

since this is for OPEN, will you be shooting minor or major loads?

[MGMorden]

The same guns with the same loads with the factory 16# spring will not cycle reliably.

If you are shooting factory loads or higher velocity handloads leave the factory spring in.

That was actually the same reason I tried going to the 14# spring in mine. I had a fairly standard target load that I used in 3 other 9mm guns. It was pretty light and in the M&P would not cycle at all with the factory spring. Swapped in the 14# Wolff spring and guide rod, and that round cycled fine, but then I started getting the failure to return to battery issue.

Since then I've just worked up another load that cycles ok and am using the factory spring/rod. Haven't chrono'd it yet though so I may be well over PF. I know from some little birdies that a chronograph will be under the Christmas tree this year, so I'll see about adjusting the load then. I do have a 15# ISMI spring for the gun in my parts box that might just strike the right balance.

[kend]

since this is for OPEN, will you be shooting minor or major loads?

That was the first thing that popped into my mind, that will be one of the deciding factors. And, using an 11# spring in a SS (I'm assuming 1911 Single Stack?) in no way compares to an 11# in an M&P, totally different guns. Kinda like comparing apples to ribs, not even close. With a comp (that works) I'm not sure you'd want to use a Tungsten guide rod. With an Open gun it's going to be trial and error and a lot of parts changing. I know Dan uses the stock guide rod in pretty much everything and his advice is certainly nothing to ignore but there are a lot of people that use lighter than stock springs and never had an issue. I run a 13 in my 9L in Limited minor and Open minor (with iron sights) and never had issues. Lightenng the slide is going to be the key to making it run with an 11# spring.

[Severian]

i have 2 M & P's on layaway with plans for a his and hers open M & P 9mm pistols. main question is the comp makers says a 11# reciol spring for for best results. but Dan for exsample says do not go below the factory spring wieght.

i have tried a 13# before but the seemed slow.

so what is the right answer?

In my M&P Pro 9mm I use an 11# ISMI spring inside a stainless captured guide rod. Have many thousands of rounds through it in IDPA and some USPSA matches. I'm shooting Precision Delta 124gr over 3.9-4.0grs of TiteGroup with an OAL = 1.138. Never a problem. I like the snappy performance.

[RWF]

since this is for OPEN, will you be shooting minor or major loads?

sorry, that is important, was not thinking, 9mm minor, right now we use 147,s at about a 130 PF. we do not reload, but buy the comp loads from tactical ammo. so far i am the only one they make the load for. Mr, Heller has been great to work with (but be damn just raise the price of 147). the first loads were at 127-128 PF i had him bump it up a little now like i said it is a 130.

thanks everyone for the feedback.

but never even owning a open gun why no tungsten guide rod for a open gun?

SSS i hope in the next month or 2 to start ordering 2 of most everything, again! well not quite again before it was one gun at a time, then the wife would steal it and i would start over again!

Edited December 5, 2011 by RWF

[Dan Burwell]

You are going to have to play with the springs to get it just right. I have two open guns one on a 4.25 in slide and one on a 5in, I have the same major load for both, one runs on the factory the other with a 13# (don't remember which is which right now).

There are so many variables mostly related to load and comp effectivness to be able to say a particular weight is going to work for you. So just order a bunch from Kenny and start playing

I would certainly recomend going with the heaviest that works for you. The main reason I always recomend the factory weight is because M&Ps don't like to go in/stay in battery with the lighter springs. You can try to balance with a lighter stiker spring, but this often leads to light hits.

[RWF]

thanks!

also Dan B i will need make an appointment for 2 M & P's for around mid feb. if all goes well.

[sdm74]

Why do people want to change the spring anyway? Does it not cycle fast enough? Is it actually slowing you down? I don't think I would feel the difference while out shooting a stage. But YOMV

[RWF]

why i do it is to get a better balance on the recoil with the ammo i am using, a heavy spring lighten's the rearward recoil but closes the slide harder makeing it front dip, and vice-vesa if go lighter.

this being our first open style pistols, i knew that a lighter spring would be needed but want to ask people had the know how.

[kend]

since this is for OPEN, will you be shooting minor or major loads?

why no tungsten guide rod for a open gun?

The heavier Tungsten is to help control the rise of the muzzle during recoil but on an Open gun the comp is supposed to do that if it's working properly. If it is then the heavier Tungsten will just add weight and make the gun too muzzle heavy. If you wind up with a lot of muzzle flip then you need to work with the comp or ammo, it should shoot flat. Guys with a lot more experience than I have can answer questions about powders and loads that will make the comp work.