guide rod for M&P Pro 9mm

[Jimmy76]

I've read on posts here about changing out the guide rod and springs on the S&W M&P Pro 9mm and my newbie question is why? I can understand needing it to go to a lighter spring, but I've read some say to stay with the stock spring pressure.

So what advantage does.....

1)changing the guide rod and going to a 13# spring?

2)changing the guide rod and keeping the stock spring pressure (15# IIRC) have?

Thanks for any help,

Jim

[MemphisMechanic]

I'm running a 13-pound ISMI spring for a Glock 34 in mine, uncut. Works great. Using the stock guiderod, too.

I can't really see any reason to replace the metal guiderod in an M&P, at least in a 9mm for Production or IDPA use.

[JeffWard]

1) Changing the guide-rod and spring.

People who shoot Production Class are trying to get as close (safely) to Minor Power Factor. These loads are quite a bit softer than factory defensive ammo. The factory springs are designed to handle defensive ammo, and manage the recoil impulse of +P loads. With softer ammo, the factory recoil spring can actually drive the barrel down as the slide slams forward. The key is to minimally "spring the gun" while still remaining reliable. Control the rearward drive of the slide from the shot, but not to slam the slide back forward over-correcting for recoil.

Jeff

[Jimmy76]

Thanks for the quick replies. I'm planning on getting set-up with Dillon equipment this month and was wondering how all this worked. I have a friend who uses a the same gun in Production that loaded up some rounds for me to try and they felt alot softer and seemed to group better than the WWB I've been using. I guess the only way to see the difference for sure is to try the handloads with the stock set-up and aftermarket parts? Any other suggestions to a newbie are appreciated!

I'm pretty new to competitive shooting, but can already see there's alot to learn/clutter your head!

Thanks

Jim

[Shibby]

I went to a 13# spring because I was getting some FTE's out of my Pro, haven't had an FTE since. I got the new guide rod because it was cheap and non-captive, so I can change recoil springs easily.

The only advantage I see to changing the guide rod and keeping the same spring weight is it is easier to change the recoil spring when you need to.

If your gun runs fine with the stock springs, I would say leave it alone.

[S391]

Is a 13 lb. spring lighter or heavier than the stock spring?

Edited March 10, 2010 by S391

[beastfrog]

Is a 13 lb. spring lighter or heavier than the stock spring?

Lighter.

[MemphisMechanic]

Factory spring is supposedly 15, but is every bit as stiff when working the slide by hand, as a 17lb glock 17/34/35 spring.

[S391]

Interesting.... I never thought about that. Thanks for the info!

[Filishooter]

I broke my Tungsten SSS guiderod in my Pro during practice last Saturday. I didn't even notice it until after practice when I was going to clean my gun. The long part of the rod must have fallen out and I was shooting with just the recoil spring, 1911 style! Gun still functioned fine but I had to pull the pins to get the slide off as the spring was jammed into the takedown lever. The steel rod is going back in. I didn't even notice the weight was gone while shooting.

[Filishooter]

Update....we'll I was ready to dismiss my broken guiderod as the nature of being tungsten and move on to steel but Kenny saw this post and sent me another one! I'm getting all my M&P stuff from Speedshooters! Kenny is a standup guy.

[nar]

is a tungsten guiderod legal in for uspsa production? I am also having a few FTE on my wife's pro and I wonder if getting a tungsten guiderod with a number 13 spring might fix this problem?

[Sarge]

is a tungsten guiderod legal in for uspsa production? I am also having a few FTE on my wife's pro and I wonder if getting a tungsten guiderod with a number 13 spring might fix this problem?

Sure, it's legal, but make sure you don't go over USPSA listed weight.

[nar]

is a tungsten guiderod legal in for uspsa production? I am also having a few FTE on my wife's pro and I wonder if getting a tungsten guiderod with a number 13 spring might fix this problem?

Sure, it's legal, but make sure you don't go over USPSA listed weight.

Thanks!

[lcs]

is a tungsten guiderod legal in for uspsa production? I am also having a few FTE on my wife's pro and I wonder if getting a tungsten guiderod with a number 13 spring might fix this problem?

Before you spend the money, women and men new to the shooting game sometimes use a loose grip or break their wrists(limp wristing) thus causing FTE with lower power factor ammo.

[nar]

is a tungsten guiderod legal in for uspsa production? I am also having a few FTE on my wife's pro and I wonder if getting a tungsten guiderod with a number 13 spring might fix this problem?

Before you spend the money, women and men new to the shooting game sometimes use a loose grip or break their wrists(limp wristing) thus causing FTE with lower power factor ammo.

Good point, I should take the pistol to the range and run a few hundred rounds through it to see what the deal is. I think the guide rod would be a good placebo as well for my wife. If I get a new guide rod and spring and reinforce a strong grip to my wife she might think it was the guide rod, and after no more FTEs she won't doubt her skills. That would be best case of course. Im running 135 power factor and she has a FTE about every other match.

Every 400 rounds or so there is 1 FTE on her MP pro.

[DocMedic]

Wow, I just installed my SSS tungsten rod and 13lbs spring in my pro and put about 200 rounds through it. When you pull back the slide it feels like glass, Love it.

Edited April 25, 2010 by DocMedic

[JoeInKS]

Hope that this is at least roughly on the same subject........

For a person who will be mostly shooting ammo such as the typical bulk 115 grain Winchester White Box 9mm, would I be benefited by going to a lighter spring? Don't foresee doing my own reloading within the next year nor will I be using the Pro for anything other than local match shooting. Should I purchase, for instance, the aforementioned 13lb spring, cut some coils on the existing, look at getting something even lighter, etc.?

Thanks

[ebg3]

I say shoot it as is. The slide will cycle fine with the stock spring and Win. White Box ammo. Going lighter on any of the springs may cause problems.

[fiddler]

I tried a 13# spring in my Pro with factory (WWB) ammo. I found the gun runs better with the stock spring. Perhaps I'll try the lighter spring when I start reloading but for now, for me, stock is the way to go.

[millisec]

When my Pro was new and I took it to the range I had quite a few FTE's with a variety of factory ammo. The stock spring was so stiff the slide was not completely cycling and the round being ejected would get caught. I dropped in the well used spring from my old M&P fullsize and the gun has been flawless since. I started shooting heavier loads ~150 PF and I decided to try the ISMI springs plus I also wanted a spare non captured guide rod and springs. I bought 13, 15, 17 pound springs and tried the 15 first. The springs are a bitch to get in especially when new and I wonder if the full length rod would have made life easier.

Anyway the ISMI 15 was to much... talk about springy. No malfunctions but the gun was practically coming out of my hand. It only took about a mag to figure out that was not going to cut it. Needless to say I never bothered with the 17. The 13 was still much stiffer than the old factory spring but it was nice and crisp and it softened up some after a few 100 rounds and I've been using it since.

Bottom line is if your shooting factory ammo or even "normal" power reloads and not having any problems I would leave the factory captured spring installed.

[470nitro]

I tried a 13# spring in my Pro with factory (WWB) ammo. I found the gun runs better with the stock spring. Perhaps I'll try the lighter spring when I start reloading but for now, for me, stock is the way to go.

My experience was similar. When I went to a non-captured guiderod, I went with the Tungsten and really like the feel (closer to my Limited gun). Stuck with the 13 lb as it hasn't failed me in a match yet but it is marginal. Cycles better with the 15-16 (whatever it is) factory weight.