SPORT Buffer upgrades and Spring Questions....

This is a naturally overgassed 16" Carbine M&P15 SPORT (Original Version with 1/8 5R Barrel) overgassed as all are.

I'm on a mission to tune it with added mass with Buffers and "possibly" a stronger spring as I ordered a JP- Tuned and Polished Chrome Silicon Buffer Spring with 7% extra power!
(sorry for the lengthy post in advance).

I already added an H buffer awhile back and it made it much smoother, being still want to smooth it out more, but do not want to put it on the border of risking malfunctions, just want it less gassy than from the factory and maybe like 1 step below as far as it could be pushed and to where PMC .223 55gr can still be reliably fired reliably, and not risk malfunctions once a little dirty as these Carbines are known to push on and on in factory configuration, so just want to make it smoother and have less recoil/ muzzle dip, and parts wear.

Just put in a Chrome Silicone "Damage Industries" Buffer Spring (normal strength, 100x longer life expectancy and less Twangy) and haven't used it yet, but ordered a "JP enhanced spring" that is 7% stronger as an add on to an online order to get a discount.
The JP's power is HALFWAY between a White (normal power) Sprinco and a Blue (+17%) Sprinco.

So its either add the new JP buffer spring with my current H buffer,

VS

Keep in the Normal strength Damage Industries CS spring and add an H2 buffer!

Which pair would add the most reliable resistance and is that 7% extra spring power MORE, or LESS than what an extra Tungsten weight would add if I went from an H to H2 buffer with normal spring???

I still want to be able to run PMC 223 55gr, although I have more PMC Xtac 556 on hand but don't want to tune it too far.

I've read archives here of many having great success upgrading to an H2 Buffer, M16 Carrier, and Factory Spring.

So even though the Sport came with a SA BCG and I have a spare ToolCraft Nitirde M16 BCG on hand, the factory SPORT BCG is said to be terrific quality as "Microbest" makes M&P BCGs supposedly...

Any suggestions from those who have done this process??

You're way overthinking this. The M4 uses an H2 buffer (and stock spring) to reduce the cyclic rate in full auto fire. The Sport doesn't do full auto, doesn't "need" the H2.

But it's your toy and your money. I'm sure you'll find co-conspirators.

Seems like an adjustable gas block would be what I would check into. Solves your problems no matter the ammo used. They come in just about any flavor you might want .

I use exclusively IMI 5.56 FMJ ammo.

I put an H2 carbine buffer in my Sport 2, with a silica carbide spring. It changed the ejection pattern from 1 o'clock to somewhere between 2 and 3 o'clock.

I have the JP spring in one of my ARs (16") and noticed no difference anywhere as compared to the original.

For grins, I have tested a carbine buffer, H buffer, and H2 in my 8.5" pistol using basic 55 gr ammunition (PMC X-TAC 55gr FMJ-BT).

Surprisingly, I find no difference to include felt recoil or ejection pattern.

It runs fine with all 3. My brass is tossed to approximately 4 o' clock. The H2 might have tossed to about 3:45 but that's about it.

OP HERE! Thanks for all advice so far.

I'm mainly wondering if the extra 7% of the JP Spring provides more power against the BCG stronger than an extra Tungsten weight would (H2, as I already have an H which works great with factory spring), being if so and I use the (standard power) "Damage Industries" Chrome Silicone buffer Spring with possibly upgrading to an H2, although would seeing how the JP +7% power CS Spring and my H buffer would work in comparison to going the H2 route???

Due to not knowing how the extra 7% compares to the power of an extra Tungsten weight, it makes me wanna just use the standard strength Damage Industries Spring and H buffer, and possibly an H2 after testing (hopefully soon, which is why I'm asking online as range time takes awhile to find time for).

I would also worry about short stroking when using 223 if using the stronger JP Tuned spring, at least for now unless I hear any first hand accounts or spring weight to buffer weight comparison charts!

Anyone know how much stronger 7% is on a Buffer Spring compared to a Tungsten weight, as far as slowing effect?

nighttrainnc said:

OP HERE! Both are supposed to cut down on the Twangy sound when firing. [/B]

Click to expand...

When I first got my Sport2, it twanged on every shot. I took out the factory spring and used a lightly oiled rag to wipe it down. That got rid of the twang.

I did change out the spring and buffer later, only because I wanted a silica carbide spring, for longer life and they are .003 smaller in diameter, to make sure the twang never came back.

Personally I don't understand the issue with the sound. It's a good indicator of the bolt being locked back so, I like the sound. Still, if you want to get rid of it: Super Duty Chrome Silicon Buffer Spring
- LaRue Tactical

Also, about the gun being "over gassed", don't fix it if it ain't broke. If the gun is cycling properly, don't change anything.

Rastoff said:

Also, about the gun being "over gassed", don't fix it if it ain't broke. If the gun is cycling properly, don't change anything.

Click to expand...

My feeling also. My wife bought one of the early S&W's, probably made by Stag, that piles the cases in a tiny group at about 4:30. Mines kicks them forward to about 1:30 and spreads them out. Neither gun has been altered and never will be. Neither gun has ever choked.

Made a mistake, the JP tuned Spring is NOT the same as a Sprinco Blue!
The Springco Blue is +17% stronger than a factory spring, while the JP is ONLY 7% stronger than factory. Yet it is Chrome Silicone which has a much greater life span.

Yet this is in NO WAY about the Twangy sound, that's just a bonus.

The purpose of this entire thread is strictly about "Tuning a Sport using Buffers, OR a Buffer and Spring Combo" to slow the slow the cycle and extend Bolt lock time, being the gas post hole is MUCH larger than Mil-Spec (0.63 is proper, M&P rifles have close to a 0.75 gas port/journal), so even though they run great from the factory, the BCG is slamming back and forth WAY too hard compared to a properly gassed Carbine so we can tune them with Buffers and springs to make them feel like shooting a rifle that costs 3x more.

So for those who have done this, what is the heaviest buffer you had success with using where it could still cycle 223 and not **** out once dirty, and basically run much smoother, but just as reliable as from the factory???

As that gas port erodes over time, and it will, no way around it, the issue will just get worse. Adjustable gas block will alleviate all of this.

nighttrainnc said:

Anyone know how much stronger 7% is on a Buffer Spring compared to a Tungsten weight, as far as slowing effect?

Click to expand...

GO SHOOT THE STUPID THING ALREADY AND FIND OUT

nighttrainnc said:

...the BCG is slamming back and forth WAY too hard compared to a properly gassed Carbine...

Click to expand...

Hmmm, well, I don't know the right answer here. I have no idea how to tell if a BCG is moving too hard or not.

What I can tell you is that my favorite AR is ejecting the brass so that it lands at about 1:30 to 2 o'clock. If I were to film it, the brass would be seen hitting the shell deflector and bouncing forward just a little. I'm a lefty and none of the brass has ever hit me in the face. My gun has been 100% reliable over 3,066 rounds.

When an AR is over gassed, there is only one fix. Reduce the gas drive. Heavier buffers and stiffer springs may help with the symptoms, but still do nothing to fix the problem.

Many consider H and H2 buffer to be "heavy" buffers but in reality, both buffers are lighter than the original rifle buffer. Carbine buffers are too light, even when an AR is gassed right. The H buffer is the lightest buffer an AR should use.

A properly set up 5.56 AR with a carbine RE uses an H or H2 buffer and a quality carbine action spring, such as a Colt action spring or Sprinco white or blue action spring.

How a BCG group feels is a good indicator how ask AR is gassed. The ejection "chart is not. If the carrier feels like it's slamming back and it's using the proper buffer and spring, the next issue to address is gas drive. An overly large gas port can be fixed by t replacing the barrel, installing an adjustable gas block or using a micro tune gas port from Black River Tactical.

The easiest and most versatile fix is the adjustable gas block. I use the SLR adjustable gas block. It uses click stops for positive adjustments and it's rugged. If anything goes wrong with it, SLR will take care of it, no questions asked.

The most economical is the BRT Micro Port. It's not adjustable, so there are no moving parts. But the Micro ports are replaceable, do the owner can try different diameters to tune their AR. BRT Micro Ports do require the gas block gas port be threaded for installation.

Nightrainnc, to tame your over gassed Sport, install an H2 buffer with your JP spring, then tune the gas drive with an SLR adjustable gas block. If you want to keep your original gas block, use the Micro Port kit from Black River Tactical.

About my previous post- Sometimes I'm a jerk.

nighttrainnc said:

So for those who have done this, what is the heaviest buffer you had success with using where it could still cycle 223 and not **** out once dirty, and basically run much smoother, but just as reliable as from the factory???

Click to expand...

Does it come with a semi or FA style bolt carrier?

If you want to experiment with buffer weights, buy a pack
of small split shot sinkers. Drive out the roll pin on buffer,
and pull one of the weight cylinders out and fill it with split
shot...try it, pull out another cylinder, etc etc.

MistWolf said:

When an AR is over gassed, there is only one fix. Reduce the gas drive. Heavier buffers and stiffer springs may help with the symptoms, but still do nothing to fix the problem.

Many consider H and H2 buffer to be "heavy" buffers but in reality, both buffers are lighter than the original rifle buffer. Carbine buffers are too light, even when an AR is gassed right. The H buffer is the lightest buffer an AR should use.

A properly set up 5.56 AR with a carbine RE uses an H or H2 buffer and a quality carbine action spring, such as a Colt action spring or Sprinco white or blue action spring.

How a BCG group feels is a good indicator how ask AR is gassed. The ejection "chart is not. If the carrier feels like it's slamming back and it's using the proper buffer and spring, the next issue to address is gas drive. An overly large gas port can be fixed by t replacing the barrel, installing an adjustable gas block or using a micro tune gas port from Black River Tactical.

The easiest and most versatile fix is the adjustable gas block. I use the SLR adjustable gas block. It uses click stops for positive adjustments and it's rugged. If anything goes wrong with it, SLR will take care of it, no questions asked.

The most economical is the BRT Micro Port. It's not adjustable, so there are no moving parts. But the Micro ports are replaceable, do the owner can try different diameters to tune their AR. BRT Micro Ports do require the gas block gas port be threaded for installation.

Nightrainnc, to tame your over gassed Sport, install an H2 buffer with your JP spring, then tune the gas drive with an SLR adjustable gas block. If you want to keep your original gas block, use the Micro Port kit from Black River Tactical.

About my previous post- Sometimes I'm a jerk.

Click to expand...

Thanks for the info!

Unfortunately, I will not be able to do any tuning to the gas system, so I'll strictly be dealing with Buffers and possibly the JP Spring.

I have an H2 buffer in a Spike's Middie, and I highly doubt the middie needs an H2 after what I've researched so the H in the Sport may serve the Spike's middie better, and the H2 from the Spike's serve the Sport better.

Out of 3 Smith's I spoke with, all suggested the H2 and normal spring (in this case a Chrome Silicon Damage Industries normal power spring) OPPOSED to an H buffer and the JP Spring.

I figured since the JP is 7% extra power, that it would serve best with a lighter buffer.

I have a M16 ToolCraft Carrier I bought for this but have been convinced that the M&P BCG, even thought SA, is top quality and not worth changing out being it's only a 14oz difference.

Seems an H2, factory Spring, and M16 BCG is the sweet spot for these Sports as I've read in archived threads, but now thinking about it, an H2 plus that JP spring would nearly be close to the 14ozs of an M16 Carrier, so maybe it indeed wouldn't be Overkill.

One Smith said he felt like the JP spring would highten the risk of me having malfuntions down the road (likely short stroking).

Although, being an M16 Carrier upgrade is no big deal at all and is 14ozs heavier and an H2 buffer is ONLY 1.5ozs heavier than a CAR buffer, is that a good way to look at things and how an H2 plus the JP spring that doesn't drag in the tube and has more forward power wouldn't equal an M16 Carrier in theory?

Or being in in the buffer tube, does that make a bigger difference even though not nearly as heavy as the Carrier, which would slow itself opposed to the H/H2 and slowing rearward travel and the JP +7% power speeding up forward travel and lock time.

Using SLIP 2000 EWL30 also and not sure if that makes a difference being it moves carbon to the side so hoping carbon wouldn't be as much of an issues.i just do not want to tune it to being on the border of malfunctions when getting dirty or not running like a tank as the SPORTs do from the factory when they are overgassed, so I'm hoping the overgassing isn't what makes them run so well, hopefully that's just to eat a wide variety of ammo solely.

I even proposed the JP Spring with an H buffer to allow the spring to build it close to the equivalent of an H2, and was told do an H2 and not mess with the spring.

What are the Con's of an upgraded spring???

Is likely being to make the cycling too stiff or risk it being on the border of it not having enough gas? Or do many people just not do combos to be lazy and only use buffers?

They say the JP spring DOES increase muzzle dip though as it snaps forward to ensure a good and longer lock time and have like a one-two punch feeling (rear cycle and forward cycle felt), the JP is half the weight of a Blue Sprinco though so if you have tried this, I may test this out after trying an H2 with my Damage Industries normal strength CS Spring.

What should I look for? Try short stroking tests like not shouldering the rifle when firing 223 etc?

I've heard the ejection pattern tells the most when tuning, although from the factory if was hitting the brass deflector and flying out around about 4:30, a behind me to my right in a nice consistent area, but don't think it was 5 o'clock.

You are gonna make yourself crazy over thinking this. I have been experimenting with gas drive and buffers and this is the bottom line- Heavy buffers will not solve over gassing.

To Fix your problem-
-Install an H buffer or an H2 buffer and the JP spring.
-Install an SLR adjustable gas block.

The above steps will solve your problem. The SLR is easy to adjust and tuning is a snap. All of my testing was done with a full auto BCG.

To drive the point home, you will not fix your over gassing problem with a heavy buffer. Heavy buffers introduce problems of their own and will throw the system out of balance. H and H2 buffers are not heavy buffers. Think about this- correctly tuned AR carbines use a .0625 gas port and an H buffer.

Do not use the ejection pattern to try to tune your rifle. It is not reliable enough to tune correctly. Tune your AR by starting with the lock back check.

If you cannot tune the gas system, you're wasting your time. The best thing to do would be to sell it and buy a Colt AR. The Colt comes from the factory with the right gas port, springs and buffer.

An FA carrier is not 14 ounces heavier than a semi carrier, and
spring, buffer & carrier weight have no effect on lock time.

MistWolf said:

Do not use the ejection pattern to try to tune your rifle. It is not reliable enough to tune correctly. Tune your AR by starting with the lock back check.

Click to expand...

Finally someone else that doesn't worship on the alter of the ejection pattern. I've found extractors and ejectors both have major roles in where the empty cases land. I tried mentioning that on ARF.COM once.........................I still have third degree burns. I've long since forgotten my password.

I've asked this before, but it seems to have been lost. How do you know if the BCG is moving too hard? What is a "lock back" check?

I agree that ejection pattern is not a reliable test of the gas system. However, if the gun is functioning, i.e. cycling reliably, why mess with the gas system at all?

Also, I agree that the gas system can only be fixed by adjusting the gas system. Changing buffers and springs is not the answer.