9mm pro timming ?

[jaggy13]

Hey all, I have a pro on the way, still a few weeks out but am excited to run it the moment it comes in!

I currently shoot a G34 (9mm)and for my load am running a 12lb spring but feel like I could go even lighter.

My question for the group is...

Does anyone else run both a glock and M&P of similar configuration and how do the recoil springs compare? Like same = same recoil spring weight?

I know the M&P's slide is considerably heavier, my assumption would be the M&P would need even lighter springs.

I see most are happy with the 13lb spring but as before mentioned, my glock seems to need even lighter than the "norm". (stock spring still funtions)

I've looked into the tuning kits, but feel like they would all be higher weight than I need...

my current load is 124gr TMJ 4.5gr Unique making 137pf.

Looking to run in production for what it's worth.

Thanks in advance!

Edited November 7, 2011 by jaggy13

[Sin-ster]

I'm interested to hear the responses as well, as I'm making (almost) the exact same switch. (G17 ---> 9 Pro.)

I've done a bit of research, and can say that there's a couple of concerns about dropping the weight. Dan Burwell (who may chime in) suggests factory springs if you want the gun to run 100%, all of the time. Since this will be the second trigger he's done for me, I tend to give that statement a lot of weight!

There's also an issue with a lot of the new 9mm's unlocking early and resulting in vertical stringing of the shots at 20-25 yards. Needless to say, going to a lighter recoil spring should (in theory) exacerbate this problem. I'm far from sufficiently schooled in this field though, so it may just be an unfounded concern/conclusion on my part.

It may also be problematic if you're running a factory or extra power striker spring, for the sake of reliable ignition. This will certainly be the case for me, so I'm on the fence.

All of that said-- I tuned the Glock up and feel the urge to tinker on this new gun as well. I've got a SSS rod and 13# ISMI coming, just in case. Also of note and use to you is that according to what I've read (Dan included), you can drop in a G17/34 captured straight to the M&P and go to town. So you might already have everything you need to do your tweaking, if you see fit.

Glad you posted this, I'm interested to see what type of responses you get that aren't just third hand hearsay! And good choice of pistol and Division as well.

[RH45]

I don't remember how light of spring I had in my Glock 34, but, I put it in my M&P Pro, and I could shake the pistol out of battery. I put the stock spring back in my M&P. I didn't want a KABOOM!

[jaggy13]

Thanks for the reply's.

My goal is to maintain reliability as is with my g34.

Not looking to super tune anything, just want it to perform at my "tempo".

Once I got my glock tuned it seemed like it would just jump to the next target as apposed to flipping or dipping.

I do plan on shooting the stock recoil spring for a while, and I have heard other recommend the extra power striker spring.

Looking forward to getting to know this platform.

I am also curious to see how the recoil note will differ from my glock given the heavier slide.

Gonna be a long 12 week wait!

[PacMan]

Hey all, I have a pro on the way, still a few weeks out but am excited to run it the moment it comes in!

I currently shoot a G34 (9mm)and for my load am running a 12lb spring but feel like I could go even lighter.

My question for the group is...

Does anyone else run both a glock and M&P of similar configuration and how do the recoil springs compare? Like same = same recoil spring weight?

I know the M&P's slide is considerably heavier, my assumption would be the M&P would need even lighter springs.

I see most are happy with the 13lb spring but as before mentioned, my glock seems to need even lighter than the "norm". (stock spring still funtions)

I've looked into the tuning kits, but feel like they would all be higher weight than I need...

my current load is 124gr TMJ 4.5gr Unique making 137pf.

Looking to run in production for what it's worth.

Thanks in advance!

Stock spring (captured flat wound) in both G17 and M&P 9 Pro. Played around with lightter spring rates on both Glock and M&P, didn't see any noticeable improvement so went back to factory weight. 4.2 TG, 124 FMJ.

[want2race]

I ran an 11 for awhile. It's a delicate balance though. If you get light strikes, the slide is likely not closed all the way. You won't fell a difference between the 11 and the 13 except that the 13 is more reliable. Don't change striker spring! It's not a Glock, the striker spring in an M&P only changes the trigger pull weight .25# or less. If you feel you must run an 11# recoil, then you will have to reduce the striker spring weight to keep the slide closed. Once you have a few light strikes in matches you will change it back. Your grip strenth and recoil management also play into how light you can get away with.

[midvalleyshooter]

I am two matches into shooting a M&P Pro and the G34 is now my backup. I have a 13 lb spring on the stock guide rod in the 34, a Vanek trigger and grip tape. The Pro I have had a pretty good trigger out of the box and it is getting smoother the more I shoot it. The M&P just fits me, I love to tinker, but the Pro just works so at this point I'm running it box stock. Who would of thunk it!

Keith

[DWFAN]

I had a 13lb spring keep the gun out of battery multiple times, or the slide would come out of battery when the striker hit the primer.

[Sin-ster]

I had a 13lb spring keep the gun out of battery multiple times, or the slide would come out of battery when the striker hit the primer.

Eek. What was the result of the latter instance?

Did you get a light strike, or would the gun go off OOB?

I got to hold my pistol a few minutes yesterday before it went off for trigger work. I've got some re-spring stuff ready for it, just to play around-- but the more early info I can get, the better.

Edited November 10, 2011 by Sin-ster

[DWFAN]

Light strikes.

eta: I liked how the gun tracked with the 13, but it wasnt reliable enough for me. I was using federal primers, and they were all well seated. Same ammo runs 100% through all my other guns. I would have went back to the stock spring, but switched to CZ instead.

Edited November 10, 2011 by DWFAN

[RWF]

tried a #13 for awhile but it seemed to make the gun slow. went back to the #14 spring. this is my limited gun with a lighten slide. what i did notice after the fact is the lighter springs are shorter they are. i called Allen (sprinco) about this and he says they all have the same # of coils. i did talk to him about a longer 13# spring. we will try it the next time order. he always very helpful. as per may request he uses a sub spring with a full extra coil for my Pro's, which i really like, the wife does not because then the gun is to hard for her to get to slide lock. Allen sent the same set-up i liked, lighter main recoil spring and heavier sub spring to his pro shooters and they did not like either. also the gun ran with no issues either way with 115 white box and 147 down to 128 PF. but did not ever try to see if could shake the gun out of battery.

just a note. a year or so ago when i first talked to him aqbout trying a lighter spring main recoil spring he was against it.

[GlockCanMan]

When I gave up shooting my Glock 34 I was down to a 13lb spring shooting a 147gr bullet at 127-128 power factor. I am now using the same bullet out of a 5" M&P Pro with a 13lb non captured spring. No problem with mine. Haven't tried to go lower weight spring yet.

Not sure if they are the same spring length between the two guns as I never measured them.

[jaggy13]

I ran an 11 for awhile. It's a delicate balance though. If you get light strikes, the slide is likely not closed all the way. You won't fell a difference between the 11 and the 13 except that the 13 is more reliable. Don't change striker spring! It's not a Glock, the striker spring in an M&P only changes the trigger pull weight .25# or less. If you feel you must run an 11# recoil, then you will have to reduce the striker spring weight to keep the slide closed. Once you have a few light strikes in matches you will change it back. Your grip strenth and recoil management also play into how light you can get away with.

This is what I needed to hear...

What I love about my glock is how reliable it is.

I like to "tune" my pistols but reliability is paramount.

I can run rifle primers in my glock without issue and will expect the same from the M&P.

Thanks for the replies.

[69bowty]

I had a 13lb spring keep the gun out of battery multiple times, or the slide would come out of battery when the striker hit the primer.

If it was the same spring in the gun when I got it I'm pretty sure it was an 11lb or was wore out. The spring was an inch shorter then the new 13lb that's in it now. I haven't had any issues with either spring even with CCI primers.

[jaggy13]

I got to shoot a pro today side by side with my G34.

The Pro had a 14lb recoil spring and an apex kit with Ram.

It shot very smooth and the recoil note was subdued compared to my Glock.

It really satiated my curiosity, I feel much better about running it right out the box for a while now.

[Sin-ster]

I got to shoot a pro today side by side with my G34.

The Pro had a 14lb recoil spring and an apex kit with Ram.

It shot very smooth and the recoil note was subdued compared to my Glock.

It really satiated my curiosity, I feel much better about running it right out the box for a while now.

I'll have mine back and ready for load development and tuning tomorrow or Wednesday. By Friday, it'll be rockin' and rolling. I'll let you know what I figure out.

[Severian]

I've got a 34 and a M&P Pro 9mm. I use 11lb springs in both. They work great with 125 PF. Never any problems with probably 5,000+ rounds through my M&P.

[Sin-ster]

Got the 9 Pro back from trigger work today. (Dan is... a magician.)

Put 300 rounds of factory 115 (Federal Champion) through it with impressive results. Going to work up the load tomorrow, shoot a match with it Sunday, and then see about messing with the spring if necessary.

Although the way it tracked with the factory stuff and the positive ejection arc it had... Chances are, I might stick with the standard spring. But I'll experiment after Thanksgiving.

[Sin-ster]

Some early results:

The Pro had a bit less recoil impulse shooting factory Federal Champion than did my G17. Given, the M&P is a little under 4oz heavier and with the extra .5" of barrel, it may be a bit heavier at the nose. Still, worth observing.

The (worn) 13lb spring in my G17 runs my handloads a bit softer than the stock spring in the 9 Pro. Now the tables have turned, and this is the only logical cause. Honestly, it's barely perceptible-- and I admittedly didn't shoot the guns side-by-side. But it certainly seemed that way to me. (Not a huge deal, as the M&P's sights track MUCH smoother and easier for me, and I don't notice any real increase in sight lift. Using the exact same Warren/Sevigny's on both, BTW.)

The initial load I worked up seems like a winner- or super-close to it. Blackout accurate. Combined with Dan's awesome trigger, I shot some asinine groups at 10 and 12 yards, with one ragged hole containing as many as 20 of 25 shots, freestyle. The rest were distinct (and mostly called) fliers, thanks to shooter error.

I struggle with accuracy, and am worse off the bench than freestyle. I also made the mistake of going for 25 yard groups WELL into my practice session, with fatigue setting in. (One thing you may notice when you get yours-- the grip is so different from a Glock that it works new muscles in new ways, and wears at your hands in different places.) All of those caveats aside, when I knew I broke a great shot, it appeared right where I expected-- POA. There was absolutely NO vertical stringing, so the gun is not unlocking early. In fact, I only heeled one shot out of 50-- the rest were within a 2-3" vertical plane from 1" left of the bull, on to the right. And I shot all of this freestyle, tired, with poor skills.

The round count is right at 800, and will be 1600-ish after Sunday. That'll be about perfect in terms of wearing in the recoil spring. Next week, before I leave for Thanksgiving, I plan to try out the lighter recoil springs and see what I can see.

In case anyone cares, the load I arrived at to this point:

124 grain MG JHPs

4.05 grains of N320 (measured across 10 charges)

1.140" OAL

.376" crimp

Federal Brass (2-3x fired)

Federal SPP

Made an average of 1044 across 45 shots fired, for a PF of 129.4. (The Low was 1034, still well within my comfort buffer zone.) Juuuuust right, although I will probably up it to a full 4.1 as Major Season (for my schedule) begins to go into effect.