modified with a jam

[chencho]

hello, I own an M&P9 moddified, it has a 4port comp and i swithced the recoil spring from a factory original to an 11pound spring.
the thing is that now when shooting, the shells do not fly away as fast and far as they used to and sometimes the shell ends up jammin between the barrel and the slide.

shoul I change a recoil sping? use stronger ammo load?
I shoot with factory ammo, do not use reloads.

 

[158Grain]

Sounds like you need a heavier spring. Try putting the stock one back in.

 

[robkarrob]

I don't understand the "as fast and as far", because a lighter recoil spring should cause the slide to recoil faster and thus the casings should fly further. The issue with using different recoil springs, as with different ammo power, is it can effect the slide operation, including FTL, FTE, and jams. The standard recoil spring is 16+ pounds, and dropping to 11 pounds is a big change.

Bob

 

[catcus-jack]

hello, I own an M&P9 moddified, it has a 4port comp and i swithced the recoil spring from a factory original to an 11pound spring.
the thing is that now when shooting, the shells do not fly away as fast and far as they used to and sometimes the shell ends up jammin between the barrel and the slide.

shoul I change a recoil sping? use stronger ammo load?
I shoot with factory ammo, do not use reloads.

Simple answer if the stock spring was working put it back in.

 

[chencho]

yes, I changed the recoil spring because of the 4" gas compensator. The indications mentioned that I should lower the pounds on the spring so I did, my logic tells me, the lower the pound on the spring, the faster the casing should fly from the gun and the further as well.

I replaced it last night, Ill shoot it later on the week and let you know.

 

[moxie]

The comp reduces recoil, reducing rearward slide velocity. The lighter recoil spring should increase slide velocity somewhat. You're going to have to play with the springs to get the desired effect.

A firm grip might help too.

 

[modraker]

Using factory ammo and an 11 pound recoil spring will give your gun a terrible beating. Some compensators require the use of +P or +P+ ammo to be effective and that's even worse.

My personal choices for ejection reliability of the 9mm M&P are: 115gr FMJ ammo - 14 pound recoil spring, 124 gr FMJ ammo - 15 pound recoil spring, 147 gr FMJ ammo - original recoil spring. I realize that it may be a bit much to be switching springs each time you shoot different ammo. So, I have settled on a 15 pound recoil spring as the in-between choice for target shooting.

 

[moxie]

Haven't found the need to fiddle with springs. My 9c is 100% stock and shoots anything with 100% functional reliability.

 

[chencho]

Haven't found the need to fiddle with springs. My 9c is 100% stock and shoots anything with 100% functional reliability.

of course, without any modifications the gun works great, the thing is I decided to jump into open division in ipsc. Why? dont ask, I had some sort of a brain farth.

in every day carry, i use a m&p9c with it I shoot idpa and it has over 10,000 rounds and works like day 1. the fs m&p9 has about 20k shots and just now that I decided to mess with it began to jam.

 

[modraker]

Haven't found the need to fiddle with springs. My 9c is 100% stock and shoots anything with 100% functional reliability.

True enough. Some retired folks, such as myself, enjoy fixing what ain't broke. Or we break 'em so we can fix 'em.

 

[Bkreutz]

Or,,,"If it's not broke, fix it until it is".

 

[chencho]

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This is how it looks when it jams, with a 13pound spring the 124grain loads are not giving any problems yet.
Ill let you know and thanks

 

[modraker]

Chencho, I have to say this is one strange looking jam. What is keeping that fired brass in place? The back lip doesn't appear to be in contact with the extractor and the front edge looks like it's not touching anything.

 

[chencho]

the fired brass is locked between the upper part of the barrell and the center part of the slide. And you are correct, the brass is not in contact with the extractor.

 

[modraker]

Would you have another photo showing the jam from the top? Is your 13lb recoil spring combined with the 124gr factory ammo still working well for you?

 

[chencho]

yes, it kept jamming, with 13 and 11 pound spring, 124grain bullets, here are a couple more picts that might help solve the mistery

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[modraker]

Wow, that empty didn't even get a chance to go sideways before it got caught by the barrel. Could the ejector be damaged? I hate to say it but limp wristing can cause this also. One must offer enough resistance to the pistol as it cycles or the slide will not have the necessary energy as the fired brass contacts the ejector.

Which brand of recoil spring are you using? Typically, it is either Wolff or ISMI.

Compensated barrels sometimes need +P ammo to be effective. Have you tried those?

 

[chencho]

the srpings are ISMI, I´ve been shooting for a couple of years now and that gun never gave problems until now. I would discard the limp wristing.
I did change the ejector to an APEX hard steel ejector, I´ll try to change it back and see how it works.
We can also discard the use of +p ammo is so expensive!!!!

 

[modraker]

I did change the ejector to an APEX hard steel ejector, I'll try to change it back and see how it works.

Apex doesn't sell an ejector so you must mean the extractor. The extractor hooks on to the lip of the brass case and pulls it out of the barrel's chamber as the slide cycles. The brass then contacts the ejector which is a steel finger-looking protrusion on the left side of the frame. This is what turns the brass and the energy of the collision propels the brass out of the port.

Since you appear to have what is known as a Failure-to-Eject, it means there is not enough energy at the collision point of the brass and ejector to throw the brass out of the ejection port. You are losing that energy somewhere and the usual suspects are: weak ammo, limp wristing, too powerful of a recoil spring and damaged ejector and/or extractor.

What brand is your compensated barrel? Your problems started after you installed it so I'm trying to think of how it may be contributing to the problem.

 

[Bkreutz]

Take a picture with the slide off, maybe the ejector isn't there? (it just sits in a pocket in the rear block) It wouldn't be hard to leave it out.