almost new M&P 15 Sport jamming

[Seademhawks]

gun smiths

It seems the more knowledge people have about firearms, the stranger their advice gets to a simple question. Basically if you bought a firearm that has a lifetime warranty, and it doesn't go *BANG* when you pull the trigger, send it back to the manufacturer. You shouldn't be worrying about too much or too little oil, this or that, or anything else brought up. In a SHTF situation the last thing you want is an undependable firearm.
I have a MAC-90 that has never failed me. Not once, no matter how poorly I treat it. I have been shooting it for around 25 years. However, my new S&W Sport II has been garbage so far. It's going back.

 

[cyphertext]

How many times can a dead cat bounce?

 

[rtquig]

It seems the more knowledge people have about firearms, the stranger their advice gets to a simple question. Basically if you bought a firearm that has a lifetime warranty, and it doesn't go *BANG* when you pull the trigger, send it back to the manufacturer. You shouldn't be worrying about too much or too little oil, this or that, or anything else brought up. In a SHTF situation the last thing you want is an undependable firearm.
I have a MAC-90 that has never failed me. Not once, no matter how poorly I treat it. I have been shooting it for around 25 years. However, my new S&W Sport II has been garbage so far. It's going back.

In a SHTF situation you want to be able to remedy the problem yourself and can't say "hold on until my firearm returns from the factory".

 

[Seademhawks]

In a SHTF situation you want to be able to remedy the problem yourself and can't say "hold on until my firearm returns from the factory".

No you can't. You have to assume there won't be CLP, or any opportunity to find parts for your non-functioning firearm. You have what you have in a SHTF scenario. You can't go shopping. Your firearm should be dependable without the need to baby it. Over a period of a few years, yes, but if the SHTF only lasts for a few weeks or months you shouldn't need to be messing with it in order for it to function properly.

Another point to my post is in the real world. If you start messing with the functionality of your firearm then you will probably invalidate the life-time warranty. My point is simple. If it doesn't go bang, send it back. I contacted S&W today and they seem to be quick and easy to work with. They are in the process of paperwork so I can send in my Sport II for repair.

 

[rtquig]

I keep on hand parts for the BCG group. In a SHTF situation, old crankcase oil could be put on parts for lube. No firearm will go on for ever without lube, not even my Glock.
I agree that a brand new firearm that won't go bang may have to go back to the LGS, but only after you have looked at and inspected the firearm which I believe should be taken apart and cleaned before a range session. If you can't tell what the problem is, then send it back.

 

[MichiganScott]

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.

The three rings are redundant. Your AR will run with one ring. Run an Internet search.

 

[cyphertext]

The three rings are redundant. Your AR will run with one ring. Run an Internet search.

That post is over 3 years old...

 

[noro]

Hi All,

Knowing that this thread is old, and a lot of folks had the same problem moving forward, just wanted to comment. Had pretty much the same problem with mine that was returned to the factory and corrected. (mp15 short stroking thread)

Essentially, mine would fire, extract and eject, but not load a fresh cartridge. The bolt was not being blown back far enough. S&W replaced the whole bolt carrier assembly and sent it back within a month.

Their paperwork really didn't say much except that they replaced the bolt. I called S&W CS and pretty much pleasantly pushed the issue for my own knowledge. The rep I spoke to found in the factory records on my rifle, that the gas key screws had cracked and loosened, allowing a major gas leak.

The members here maintained that there was a big problem in the gas system which was verified. Being that there are no zombies at my door, I sent it back to S&W under their warranty which was honored. Bottom line was S&W paid for shipping both ways and repairing the rifle. Now, I could have bought a new BCG at my own cost and repaired it myself. BUT why should I pay out 80 to 150 for a bolt at my expense when the rifle is under warranty, and there is no civil unrest in my area at this time?

S&W CS will share any factory info on repairs if you ask and are persistent. Apparently S&W knows of a problem and will remedy it. in my case the bad screws have happened 1 in 600,000 times with S&W manufactured bolts. I noticed that, when inspected mine, that the screws were staked differently than the original bolt that came with the rifle.

 

[REM 3200]

How many times can a dead cat bounce?

Looks like 88 times SO FAR.

 

[noro]

who cares how old?

Hi Guys,

Just a thought - who cares how old a thread is if it will help someone down the road? Isnt that what this forum is all about? Helping others with a free exchange of information, ideas or opinions? Whats the big deal if a post gets updated with current info? I seem to be missing something here.

 

[cyphertext]

Hi Guys,

Just a thought - who cares how old a thread is if it will help someone down the road? Isnt that what this forum is all about? Helping others with a free exchange of information, ideas or opinions? Whats the big deal if a post gets updated with current info? I seem to be missing something here.

Because when you bump an old post and try to address members that originally posted, often they are not even active on the forum any longer.

Hang around awhile... the topics become very monotonous... even worse when you find that you are reading old posts multiple times.

 

[noro]

Cyphertext

Thanks for the explanation

 

[cyphertext]

Cyphertext

Thanks for the explanation

I don't want to discourage new members from posting... search the old threads and if you still aren't sure about your issue, post away! But preferably in a new thread vs. one that has been silent for two or three years.

 

[Univibe]

How to Lube an AR-15:

I use two lubes, (1) Breakfree CLP and (2) Breakfree LP. LP is just like CLP except it does not contain the cleaning solvent found in CLP. It is therefore more viscous and "stays put" better. If you can't find it in gun stores, you can find it online.

1. LP generously on the locking lugs, cam pin, and piston rings.
2. LP lighter where the bolt carrier group rides in the receiver.
3. CLP lightly on the firing pin, and in the fire control parts in the lower.

When I first shoot my AR, oil comes out the exhaust ports. I haven't cleaned it in quite a while; it's only necessary to keep adding lube generously.

ARs can run dirty and wet; but they can't run dirty and dry.

If generous lubrication does not cure the problem, it's the gun.

 

[Univibe]

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.

Oil on the ammo or the chamber is a bad idea.

When the gun is fired, the brass appears to the expanding hot gas to be as soft as rubber. The case expands to obturate and in this process, firmly grips the chamber wall. Oiling the ammo or the chamber means this grip is reduced; the result is an increase in "bolt thrust," which is the case's tendency to push backwards against the bolt face. Increasing bolt thrust puts more stress on the bolt face and locking lugs. Not a good idea.

 

[hugger-4641]

Since we're dragging up old threads, I'll add my own anecdotal advice. Sure, AR's might run good wet if you're using them constantly, but NEVER over lube cartridges/ chamber/receiver/magazines, and then store the rifle. It can cause a round not to fire due to oil seeping into the primer. I don't care what other "experts" might say about this, I proved it to myself years ago in several different guns. I keep most of my rifles loaded with a round chamber for my own reasons. If you clean and lube the gun, make sure you wipe out the excess .