almost new M&P 15 Sport jamming

[saltair]

I've been reading this forum and just joined today.
I have owned the M&P Sport since Oct of 2011 and after firing approx' 300 rds. of Lake City, Freedom Munitions and Remington I could not pull the bolt back more than 1/2" using the charging handle. I had to remove the rear pin and seperate the lower from the upper half and refasten which allowed me to fire a few more rounds and the same thing happened.
I sent it back to S&W and so far no problems.
I just wish they would state on the repair invoice the problem or at least what they did to repair, not even a 3 digit code that most companies use to distinguish the problem for tracking purposes. So far the Sport has worked fine and I am in NO WAY bashing S&W. They make great products and they stand by their warranty.
If any one knows what the problem could have been please share.

 

[oneyeopn]

I've been reading this forum and just joined today.
I have owned the M&P Sport since Oct of 2011 and after firing approx' 300 rds. of Lake City, Freedom Munitions and Remington I could not pull the bolt back more than 1/2" using the charging handle. I had to remove the rear pin and seperate the lower from the upper half and refasten which allowed me to fire a few more rounds and the same thing happened.
I sent it back to S&W and so far no problems.
I just wish they would state on the repair invoice the problem or at least what they did to repair, not even a 3 digit code that most companies use to distinguish the problem for tracking purposes. So far the Sport has worked fine and I am in NO WAY bashing S&W. They make great products and they stand by their warranty.
If any one knows what the problem could have been please share.

It really sounds like your BCG was getting jammed at an angle, but without being able to see the wear marks in your upper or on your BCG it is hard to tell. That is one of those things that make you go hmmmmm!

 

[isaidme1]

My M&P had problems like this right out of the box. They are over gassed as stated above. I swapped out the stock buffer for an H2 buffer from Spikes Tactical and solved the FTE and feeding jams.

 

[TangoFoxtrot]

Like all the others stated run it wet or another option is to put some bearing grease on the rails of the BCG.

 

[JaPes]

Like all the others stated run it wet or another option is to put some bearing grease on the rails of the BCG.

That's what I do before going to the range. I put a dab of high temp bearing grease on my finger, and put a very light smear on the rails. A little goes a long way.

When I get home, clean rifle as normal. Quick light coat of CLP on the BCG for storage.

 

[oneyeopn]

I use the copper high temp grease on mine, made to take a little more heat. Works like a champ but pretty pricey. If I didnt have it for brake jobs, lube the back of the pads so they float freely and dont squeal, I probably wouldnt have it

 

[AuDoc]

Id love to know what was wrong as well. I just joined here searching for just this sort of problem. I purchased an M&P 15 several months ago and have exactly the same problem. Taking back to store Monday. Here are my cartridges.

 

[raymo2u]

My friend is having this same problem with his m&p and i am with my mossberg 715t-chopping the lead out of the casings! anyone know why this is happening?

 

[AuDoc]

Bloody unnerving isn't it? After reading this forum Ill be taking my rifle back to S&W to have them sort it.

 

[JaPes]

Wow. This thread resurrected itself. I'm sure S&W will sort out the issue with your rifle. I've only had one instance of a cartridge getting jammed up like that, and not on my S&W. It happened on my home built AR. The best I could figure is that a lightly charged cartridge didn't provide enough gas to fully cycle the BCG. The short stroke caught the round while it was tilted and jammed it into a lug.

Drop mag, clear the action, triple confirmed the rifle was in a safe condition. Separated the upper from the lower, then shined a light down the bore from the muzzle end to check for a bore obstruction. No barrel obstruction. Reassemble & continued my range session.

 

[SmokeStack Lightning]

I agree with you about believing everything out of a DI's mouth lol but in the article I posted I was having the carriage getting cocked on me like in the top left picture and that did stop that problem and it was the same thing in boot camp. But at the same time I do see your point about over lubing especially the dirt and getting excessive oil on the rounds is a big no-no.

Wonder if the practice of oiling the magazines to prevent jams was taught before the introduction of the 'anti-tilt' follower??

Before the ATF was introduced some magazines did have a tendency to allow the rounds to tilt in the magazine causing mis-feeds and a little oil would help alleviate the tilting problem.

These days I just disassemble my mags and wipe the internals down with an oily cloth cuz I ditched the ones that weren't ant-tilt.

The SS magazines I own are Teflon coated on the inside.

 

[AuDoc]

Update:

Just picked it up last night from being sent back to Smith & Wesson. Haven't had a chance to shoot it yet but it appears someone has run it through its paces, outside of barrel and gas tube under handguard looks like it got pretty warm and BCG is coated in black residue.... I was actually glad to see this as it seemed to indicate to me at least someone got her to run. Broke it down and cleaned it after I got home to see if I could see evidence of something different as S&W sent no information as to what was done, if anything. The lube on the recoil spring smelled different and the bolt was much smoother in the carrier and of course the black residue were all I could find.

Today I received an e-mail from the store that sent it in for me and was told, "We did in fact send in your gun for repair because of the feed ramp and chamber not aligning. When Smith and Wesson send repaired firearms back to us, they just send and invoice with the Serial Number listed and say that the gun has been repaired to Smith and Wesson’s specifications and if there are any questions to call and inquire."

I plan to shoot it this weekend, hope it works.

Thanks for the informative thread, been a pleasure.
Doc

 

[spad124]

I took the M&P15 Sport shooting again yesterday. All shots were from a concrete benchrest covered with a padded blanket and shooting from sandbags and rest. All ammo was Remington UMC 55 gr factory cartridges purchased from Walmart. The bolt was liberally sprayed with Breakfree CLP and the inside of the receiver was liberally wiped with the CLP. Here is my firing procedure. . . .

I did look for problems with the gas system but that appears fine. Thanks in advance for tips.

I purchased a new Sport in early October. I was just able to put the first rounds through it over Thanksgiving. Using American Eagle 223 and a Thermold 20 round mag my Sport functioned perfectly regardless of loading technique. No jams. Very accurate-3 of 5 touching at 25 yards with open sights. Empties land at 4:00 about 6 feet back. Very happy with my Sport.

From the problem you describe I suggest sending your Sport and the mag it came with back to S&W for warranty. Your Sport is basically new. At least give them the chance to evaluate it and repair or replace the upper.

My Sport had a cosmetic defect when i received it--the barrel was scratched, maybe when the FSB was installed. I bought the Sport through the Internet and the seller would not exchange. (Good reason to buy from your LGS- shame on me). I explained the problem to S&W and they replaced the entire upper under warranty.

For warranty go through customer service at the S&W website. They pay shipping both ways through FedEx and give you tracking numbers to follow progress both ways. Return delivery is to your door, but the driver needs an adult signature. I had FedEx hold my return at their service center and picked it up from their service center. My warranty return took 4 weeks. I also sent a S&W 686 revolver in for recall once, and that recall turnaround took 10 days. I've had S&W revolvers for
25+ years. Because of my experience with S&W revolvers when I bought an AR I bought a S&W.

 

[Rising2ndSun]

I think it is important to note that the firing pin on this rifle is free floating and applying the safety only prevents the trigger from releasing the hammer. Theoretically, you can have a chambered round and drop the rifle and end up with a discharge since there is no fire pin block or retainer for the pin.

 

[ditto1958]

And you think S&W is the authority on ARs? They are just repeating the same myth, started by the same sources, we've been talking about.

Again, align the gas rings and shoot the thing. Stop believing rumor and test it yourself.

LOL. Well... who IS the authority on AR's? Eugene Stoner? Ruger puts the same instruction in their owners manual. They got in the AR business later than Smith did.

I'm gonna align mine some time and see if it still works.

 

[cyphertext]

LOL. Well... who IS the authority on AR's? Eugene Stoner? Ruger puts the same instruction in their owners manual. They got in the AR business later than Smith did.

I'm gonna align mine some time and see if it still works.

I hope you aren't expecting Dragon to answer you, since the post is three years old and 99% of the guys who responded are no longer actively participating in the forum.

 

[Shootingfun]

I recently purchased a M&P 15 Sport. I have had some problems with the gun jamming. I am using the stock pmag and bushmaster 30 round magazines that came with the gun. I am shooting Remington PMC factory .223 ammo purchased from Walmart. I have fired the gun about 80 -100 times. If the bolt and receiver are not well lubricated with Breakfree CLP or Rem oil (or other such lubricant), the gun will jam. Specifically, the gun will lift the cartridge from the magazine but will not push it into the chamber. The cartridge will get caught between the bolt and the chamber. The cartridge case will be well dented near the shoulder so bad the cartridge will have to be discarded. This problem happened about 1 in 3 rounds when the gun was first fired. It now happens about 1 in 8 times. Several shooters of ARs at my gun club have observed this problem with my rifle and tell me the gun just needs to be shot in rather than sent back to Smith and Wesson for repair. The fired cartridge cases have observable scratches on the case necks and the case bodies. I am interested in getting readers opinions and advice. Also, what 3 shot groups are reasonable at 100 yards? Thanks in advance.

I was going to mention the same thing, I installed a new buffer spring and H1 buffer in mine and that helped with slowing down the timing on it. I agree with others, and yes the M&P 15 Sport is over gassed. With the original spring and carbine buffer, it would extract the casings at 1:00 O'clock, with the new spring and H1 buffer right at 3:00 O'clock.

 

[uncledoggle]

I hope you aren't expecting Dragon to answer you, since the post is three years old and 99% of the guys who responded are no longer actively participating in the forum.

Glad someone else has noticed that this ol' equine has expired. or at least should have.

 

[peteinpa]

On the gas ring thing, They operate just like piston rings in an engine. Every engine I've worked on (cars and motorcycles)not only has the gaps NOT lined up but has an exact location for the gap of each ring listed in the manual.

 

[crracer_712]

I hope you aren't expecting Dragon to answer you, since the post is three years old and 99% of the guys who responded are no longer actively participating in the forum.

don't really actively participate, read a lot, just wanted to say I did have a spot on post on the first page of this thread

Actually, Since this was brought back to the top, I didn't at first notice the date until I got to MY post! But I was thinking, hmmm, this sounds similar to the way my Ruger AR556 started out....