Buffer Question

Ricrock

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I have a Sport 2 with the Buffer it came with. I have been told the gun is overgassed and I should run a H or H2 buffer instead.

What is overgassed? And what does it do? Do you suggest I change out the buffer to one of these two? What results will I expect to experience?

Also, should I change the spring out too?

Thanks for your help with this question.

Rick
 
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Some people like to tweak the function of the rifle based on the gas port size, gas system length and ejection pattern. I've heard (never seen) that an over gased rifle can wear out your components like the bcg more quickly over thousands of rounds. A possible benefit might be an ever so slightly softer shooting rifle and longevity to the bcg. My opinion...if it runs dependably leave it alone. All too often I see threads on here where someone is trying to problem shoot their rifle after making these types of mods. The recommendation to fix it-return it back to stock configuration.

I will say that I've been through this on a sig m400 and didn't notice a difference. People like to tinker and make "upgrades" based off the opinions of internet experts and tactical 'operators.'
 
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1. Have you fired the weapon?
If yes, proceed to step 2.
If no, go to the range and fire weapon, then proceed to step 2.

2. Did the weapon operate reliably?
If yes, then why do you want to monkey with it?
If no, call S&W for repair and begin process again when weapon is returned to you.
 
In all seriousness, if you are only going to shoot 5.56 rounds such as M855 or M193, you could run a heavier buffer. If you are going to shoot Tula, Monarch, or cheap gun show reloads, a heavier buffer could affect the reliability.

The rifle is a little over gassed to insure reliable operation with a wide range of available ammunition.
 
This chart mirrors my experience shooting XM855 in my 16in carbine (not a Sport).



I wasn't concerned about premature wear, but rather that my rifle was hard shooting. Ejection was around 1:00-1:30.

Installed a heavier buffer (Spikes ST-T2). Eh...

Installed an adjustable gas block (Syrac Ordnance). I think the adjustment screw is wide open when new and it ejected about the same as before. As I started started turning down the gas you could see the brass change ejection at each adjustment. I stopped around 4. Significant difference in felt recoil and muzzle rise. I also removed the Spikes. Very satisfied.

Next I installed a brake (Lantac). Muzzle barely moved after that. Happy camper. :):)

Like an entirely different rifle and has been 100% reliable.
 
Ricrock wrote:
I have been told the gun is overgassed...

Who told you that, what was their criteria and do they have the requisite knowledge and experience for formulating that conclusion?

The S&W M&P-15 Sport II is a basic AR-style rifle made by a reputable, experienced company configured to work reliably in the vast majority of conditions with the vast majority of ammunition. It is well suited to target shooting, self-defense and putting game on the table.

Personally, I would leave it just as it is. That's what I have done with both of my Sport IIs.

Or, I would learn from ChatanoogaPhil's experience that the solution was to replace the gas block, not the buffer. Keep in mind that for most people, replacing a gas block is major surgery and depending on your skill as a gunsmith may best be left to a professional.
 
Keep in mind that for most people, replacing a gas block is major surgery and depending on your skill as a gunsmith may best be left to a professional.

It's not as easy as loading a magazine, but removing an A2 front sight isn't too bad.

[ame]https://www.youtube.com/watch?v=l4rkeCzwteo[/ame]
 
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