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Does anyone have experience with pigtail gas tube,or the Fatboy gas tube on a 16" bbl ?
Lessening felt recoil on a M@P sport
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JaPes
Member
Please forgive my ignorance, but in what way does swapping out to a "pigtail" or "fat-boy" gas tube decrease perceived recoil? All the gas tube does is provide the conduit through which the tapped off combustion gasses provide the energy to cycle the bolt. The end of the gas tube still has to fit into a standard gas key.
Recoil energy is recoil energy no matter what, cant cheat that. What you're looking to do is either try and counteract the recoil energy at the muzzle and/or tune the travel of the BCG as it reciprocates.
If you want to decrease how you perceive recoil, there are different methods.
1. You can increase the static mass the gas has to overcome in order to cycle the bolt. Slowing down the bolt will lessen perceived recoil. This can be achieved by installing a heavier buffer (H, H1, H2). You can install a heavier full-auto bolt carrier assembly. Keep in mind that any change comes at a price. Increase amount of static mass the combustion gasses must overcome, you can induce short stroking, weak ejection. Your rifle may become sensitive to the bare minimum propellant charged practice ammo.
2. Increase the progressive resistance the combustion gasses must overcome. Install a stronger recoil spring. Install a hydraulic buffer.
3. You can install a muzzle brake. Redirect the combustion gasses coming out of the muzzle end to counteract the force of the recoil energy.
4. Install a softer recoil pad on your butt stock.
Recoil energy is recoil energy no matter what, cant cheat that. What you're looking to do is either try and counteract the recoil energy at the muzzle and/or tune the travel of the BCG as it reciprocates.
If you want to decrease how you perceive recoil, there are different methods.
1. You can increase the static mass the gas has to overcome in order to cycle the bolt. Slowing down the bolt will lessen perceived recoil. This can be achieved by installing a heavier buffer (H, H1, H2). You can install a heavier full-auto bolt carrier assembly. Keep in mind that any change comes at a price. Increase amount of static mass the combustion gasses must overcome, you can induce short stroking, weak ejection. Your rifle may become sensitive to the bare minimum propellant charged practice ammo.
2. Increase the progressive resistance the combustion gasses must overcome. Install a stronger recoil spring. Install a hydraulic buffer.
3. You can install a muzzle brake. Redirect the combustion gasses coming out of the muzzle end to counteract the force of the recoil energy.
4. Install a softer recoil pad on your butt stock.
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JaPes
Member
I thought about the increased diameter gas tube. The claim is that the increased volume of the gas tube will somehow reduce the energy provided to cycle the action, hence slowing down the action.
You're a retired plumber, your experience is better than mine in this regard. Thinking logically.
When popping off rounds, the gas tube will always have some gas in it. It doesn't exist in a vacuum state. If the opening the gas exits is increased, then you'll get a softer impulse of gas than a narrower exit opening.
Because the end of the gas tube must dock with a standard gas key and they can't change that diameter by much, you're going from a fat tube to a small exit point causing a venturi effect.
bah... it's late... and I'm not thinking straight.
Buy one. Try it out.
You're a retired plumber, your experience is better than mine in this regard. Thinking logically.
When popping off rounds, the gas tube will always have some gas in it. It doesn't exist in a vacuum state. If the opening the gas exits is increased, then you'll get a softer impulse of gas than a narrower exit opening.
Because the end of the gas tube must dock with a standard gas key and they can't change that diameter by much, you're going from a fat tube to a small exit point causing a venturi effect.
bah... it's late... and I'm not thinking straight.
Buy one. Try it out.
JaPes
Member
... but then water doesn't compress... gasses do... which means...
.... I need sleep.
.... I need sleep.
Rick_A
Member
An adjustable gas block is another option.
Maybe I sound flippant, but, really? Felt recoil on a 5.56 a problem? I guess you could try a PAST shoulder pad.....
I know the heavier the rifle the lower the felt recoil......maybe duct tape some lead to the butt?
Sorry, but I'm really having a hard time with this one......
I know the heavier the rifle the lower the felt recoil......maybe duct tape some lead to the butt?
Sorry, but I'm really having a hard time with this one......
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shawnfergie
Member
I imagine you are talking about changing the recoil impulse rather than lessening the recoil. I had a problem with my Sport wanting to drop the muzzle and my CTR stock was smacking my cheek in an unpleasant way. Nothing terrible but I didn't like my teeth chattering.
I installed a Spikes T2, Cheap YHM muzzle comp and the extended magpul stock pad. The stock pad alone made it so the CTR stock wouldn't move upwards on my cheek and the T2 / YHM brake combo helped even more.
I installed a Spikes T2, Cheap YHM muzzle comp and the extended magpul stock pad. The stock pad alone made it so the CTR stock wouldn't move upwards on my cheek and the T2 / YHM brake combo helped even more.
CrustyShellback
Member
OK... someone has to say it. A10 came close... 
What recoil?
Seriously, I just spent 4+ hours this Monday, putting 430 rnds downrange firing a Mini-14 and AR15. Shoulder never got tired, or sore... and I've had freakin' open heart surgery. No bruise, nor tenderness afterwards, either.
Of course, if shawn explained your situation, please disregard. Firing those two weapons, I certainly do notice a difference in the way they shoot/handle. The "recoil" is completely different, but my AR benefits from a muzzle break and is a bit heavier. To me, they both feel like springs pushing back against my shoulder. The Mini tends to walk up more, if not paying attention.
What recoil?
Seriously, I just spent 4+ hours this Monday, putting 430 rnds downrange firing a Mini-14 and AR15. Shoulder never got tired, or sore... and I've had freakin' open heart surgery. No bruise, nor tenderness afterwards, either.
Of course, if shawn explained your situation, please disregard. Firing those two weapons, I certainly do notice a difference in the way they shoot/handle. The "recoil" is completely different, but my AR benefits from a muzzle break and is a bit heavier. To me, they both feel like springs pushing back against my shoulder. The Mini tends to walk up more, if not paying attention.
The pigtail gas tube mimics the length of a mid-length gas system. This should lower the pressure in the carrier about 20% over stock. This will result in the bolt staying locked longer. I've got reservations about reliability on this if used for defensive purposes.
The suggestion about heavier buffers also will increase dwell time or the length of time the bolt stays locked. Both the mentioned gadgets will reduce the carrier velocity slightly and the reaction from the carrier bumping the end of the buffer tube. However, the heavier buffer will also increase the jolt when the carrier moves forward, causing the muzzle to dip slightly.
As others have mentioned, the recoil impulse of the AR in 5.56 x 45 mm doesn't amount to much. Just over 3 ft/lbs for the cartridge firing. Low mass carriers and different action/buffer springs (DO NOT do this on a firearm intended for defensive use!) will also change recoil characteristics. This is potentially spending a lot of money to mitigate something that doesn't amount to much in the first place.
No insult intended, but perhaps you need some instruction on how to actually use the weapon system. Poor technique can result in unpleasant results. BTW, there's some difference of opinion on this, but if you're sticking your nose up against the charging handle, please lengthen the stock and try it with decent nose clearance from the charging handle. Might change your opinion if your nose isn't being whacked every time you pull the trigger.
The suggestion about heavier buffers also will increase dwell time or the length of time the bolt stays locked. Both the mentioned gadgets will reduce the carrier velocity slightly and the reaction from the carrier bumping the end of the buffer tube. However, the heavier buffer will also increase the jolt when the carrier moves forward, causing the muzzle to dip slightly.
As others have mentioned, the recoil impulse of the AR in 5.56 x 45 mm doesn't amount to much. Just over 3 ft/lbs for the cartridge firing. Low mass carriers and different action/buffer springs (DO NOT do this on a firearm intended for defensive use!) will also change recoil characteristics. This is potentially spending a lot of money to mitigate something that doesn't amount to much in the first place.
No insult intended, but perhaps you need some instruction on how to actually use the weapon system. Poor technique can result in unpleasant results. BTW, there's some difference of opinion on this, but if you're sticking your nose up against the charging handle, please lengthen the stock and try it with decent nose clearance from the charging handle. Might change your opinion if your nose isn't being whacked every time you pull the trigger.
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SiGfever
Member
The Smith's are over-gassed, install an "H2" buffer and drive on.
Maddmax
US Veteran
bhayles
Member
OK... someone has to say it. A10 came close...
What recoil?
What he said.
In the past I've had a .300 Win mag and a 10 ga double...THOSE had recoil...
My 5'3" wife who loves shooting and 5'7" 14 year old stepdaughter who doesn't and is a bit prissy are asking the same question when they read the OP...What recoil?
JaPes
Member
I'm not going to rip into the OP. I agree that .223/5.56 recoil is easily managed. Maybe the OP has a physical limitation we don't. Maybe the OP just wants to tinker. I've tinkered to no end.
OP, if you want to decrease perceived recoil install a H or H2 buffer and a muzzle brake.
OP, if you want to decrease perceived recoil install a H or H2 buffer and a muzzle brake.
bhayles
Member
I don't mean it to be "ripping into the OP"...I'm just having a hard time understanding what there is to fix. I realize there is SOME recoil...heck, even a 22LR has a little...but, to me at least, its not even noticable. Honestly, if a fly lands on my nose during the trigger pull I notice the tickling from that more than even noticing the recoil when the gun goes "Bang!".
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eschoendorff
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Is it possible that some of the M&P15s have more recoil than others?
I came home the other day with bruises on my shoulder/peck area. That evening I saw them in the mirror and could not for the life of me figure out what had caused them - it didn't occur to me that the recoil was THAT bad (besides, I had done other yard work that day and at first figured I must have done something in the yard). I keep a pretty firm grip on my rifle and pull it in to my body. Could that be the problem?
Didn't mean to hijack the thread, but I hate to admit that I have some idea what the OP is talking about.
Could some of these units be WAY over-gassed?
I came home the other day with bruises on my shoulder/peck area. That evening I saw them in the mirror and could not for the life of me figure out what had caused them - it didn't occur to me that the recoil was THAT bad (besides, I had done other yard work that day and at first figured I must have done something in the yard). I keep a pretty firm grip on my rifle and pull it in to my body. Could that be the problem?
Didn't mean to hijack the thread, but I hate to admit that I have some idea what the OP is talking about.
Could some of these units be WAY over-gassed?
bhayles
Member
I suppose its possible, but I can't see how a gun from a quality company could have that much variation between guns of the same model.
I've only shot one Sport...heck, I've only shot one AR/223/5.56 of ANY kind, make, or model, so I have nothing to compare. With MINE, for ME, I just don't notice any recoil. YMMV
Maddmax
US Veteran
You take blood thinner ? That can do it.
shawnfergie
Member
I've had my sport give me a bruise before. Same with my father in law. I'm late 20s and no blood thinners. I believe my sport is over gassed and since that trip I have added a YHM brake and the CTR extended pad. Both seemed to help a great deal.
Also I have a brand new 15" Viking Tactics rail to install.
Over gassed or not she sure does shoot nice.
Also I have a brand new 15" Viking Tactics rail to install
. Over gassed or not she sure does shoot nice.
LimaCharlie
US Veteran
I had mercury recoil suppressor tubes in the stock of a .458 Lott to lessen felt recoil. I don't know if they are available for a .223. 
shawnfergie
Member
Do those mercury tubes actually work for large calibers?
