AR15 Help
AR15 Help
Took the Bushmaster AR15A2 out today, overall it shot great with no malfunctions at all.
I noticed what feels like a vibration in the butt stock, a quick Google search says this is normal. Hell on one site some one asked if the poster had ever fired a M16/AR15 as that is normal. Call me stupid but in my 23 years in the Air Force having to qualify on the M16, I never once felt a vibration in any M16 I shot.
So is this normal or not?
Is there a way to fix this?
What should I look at as the culprit?
Other than the vibration driving me nuts, fun was had by all, took out the AR15A2, AR15M4, M91, M91/30, M44, MAS36, and No4 Mk1. My nine year old GD fired her first real rifle today, my son's AR15M4 and my AR15A2, she liked the A2 the best.
I noticed what feels like a vibration in the butt stock, a quick Google search says this is normal. Hell on one site some one asked if the poster had ever fired a M16/AR15 as that is normal. Call me stupid but in my 23 years in the Air Force having to qualify on the M16, I never once felt a vibration in any M16 I shot.
So is this normal or not?
Is there a way to fix this?
What should I look at as the culprit?
Other than the vibration driving me nuts, fun was had by all, took out the AR15A2, AR15M4, M91, M91/30, M44, MAS36, and No4 Mk1. My nine year old GD fired her first real rifle today, my son's AR15M4 and my AR15A2, she liked the A2 the best.
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
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Re: AR15 Help
All of them I have ever shot kind of go SPROING, when shot. It is that spring in the ass end of it. Perhaps that is causing the vibration.
“Freedom is the right to tell people what they do not want to hear.” George Orwell, English novelist, essayist, and critic, 1903-1950
Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive. It would be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience.
C. S. Lewis
Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive. It would be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience.
C. S. Lewis
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Re: AR15 Help
Sounds like the ones I have fired, I don't have extensive experience with these but I found them noisy and rattily, then again I am a vintage bolt action guy. You do have that big recoil spring inside the buttstock, is the tube loose or damaged in some way?
Leave it as it is. The ages have been at work on it and man can only mar it.
Don't hit at all if it is honorably possible to avoid hitting; but never hit soft.
Theodore Roosevelt
Don't hit at all if it is honorably possible to avoid hitting; but never hit soft.
Theodore Roosevelt
Re: AR15 Help
Normal. It's the buffer spring inside of the receiver extension doing it's job.
Threadkiller extraordinaire...
Re: AR15 Help
My oldest son who just punched from the USMC, and is staying with us with his family, made an interesting observation. In the AF you use training rifles, how many thousands of rounds have gone through them, they are most likely worn out to a point, hence no sound. He was a firearms coach during his I&I tour and stated every M16 they had made that noise some worse than others.
I fired the first shot and thought damn something is loose or broken! After that I found myself anticipating the vibration, versus concentrating on my sight picture.
I fired the first shot and thought damn something is loose or broken! After that I found myself anticipating the vibration, versus concentrating on my sight picture.
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
- Junk Yard Dog
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Re: AR15 Help
If you ever need to use that rifle for real you will not notice that irritating sound at all.
Leave it as it is. The ages have been at work on it and man can only mar it.
Don't hit at all if it is honorably possible to avoid hitting; but never hit soft.
Theodore Roosevelt
Don't hit at all if it is honorably possible to avoid hitting; but never hit soft.
Theodore Roosevelt
Re: AR15 Help
Did they take the Atchisson devices out of the ones you shot in the AF?
Seriously, they should be tight. You will hear the spring, until you replace it with a flat wound spring. Check the "castle nut" (Stock lock ring ) on the buttstock, and tighten it down.
Seriously, they should be tight. You will hear the spring, until you replace it with a flat wound spring. Check the "castle nut" (Stock lock ring ) on the buttstock, and tighten it down.
"Igitur qui desiderat pacem, praeparet bellum." -Publius Flavius Vegetius Renatus
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
Re: AR15 Help
I took the buffer and spring out to check them. Spring measured out at 12 3/4 inches. The buffer when you shake it makes a sound between a can of spray paint or a paint pen. Don't know what would be concidered normal in the noise range.
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
Re: AR15 Help
That's normal. If it worries you Midway and Brownell's sell buffers of many types. As long as you have it out, a flat wound spring is a worthwhile investment.
"Igitur qui desiderat pacem, praeparet bellum." -Publius Flavius Vegetius Renatus
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
Re: AR15 Help
All of my buffers, including my Colt and BCM "H" buffers rattle. It's normal.
Threadkiller extraordinaire...
Re: AR15 Help
That's what everyone keeps telling me, I just never heard it/felt it when shooting the M16 in the AF. Retired in 2008 and I think I last fired the M16 in 2006.RazorBurn wrote:All of my buffers, including my Colt and BCM "H" buffers rattle. It's normal.
The noise, vibration was so noticeable it caught me by surprise. Best way to describe it is to take a fiberglass pole and hold it straight out in front of you, then have someone hit the end of it. That wobble is what it felt like, with the spring noise.
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
Re: AR15 Help
How is the upper to lower fit? I have seen this be pretty loose on some rifles. That might cause said wiggle. I put one of those rubber spacers in mine and the upper to leer fit is quite tight now.
“Freedom is the right to tell people what they do not want to hear.” George Orwell, English novelist, essayist, and critic, 1903-1950
Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive. It would be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience.
C. S. Lewis
Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive. It would be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience.
C. S. Lewis
Re: AR15 Help
Pretty tight fit, can't wobble it by hand, tighter than ones I shot in the AF that is for sure.millman wrote:How is the upper to lower fit? I have seen this be pretty loose on some rifles. That might cause said wiggle. I put one of those rubber spacers in mine and the upper to leer fit is quite tight now.
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
Re: AR15 Help
That's why I (jokingly) mentioned the Atchisson Device. The Air Force has used them for Basic Training and qualifications. (so I've heard from several AF vets.) You wouldn't hear the spring shucking up and down the buffer tube with the Atchisson Device, because it has an internal recoil spring. How do I know this? Because Army ROTC used them also. First time I shot an M16(A1) was with .22's! And I got stuck cleaning them because I "liked guns".ffuries wrote:That's what everyone keeps telling me, I just never heard it/felt it when shooting the M16 in the AF. Retired in 2008 and I think I last fired the M16 in 2006.RazorBurn wrote:All of my buffers, including my Colt and BCM "H" buffers rattle. It's normal.
The noise, vibration was so noticeable it caught me by surprise. Best way to describe it is to take a fiberglass pole and hold it straight out in front of you, then have someone hit the end of it. That wobble is what it felt like, with the spring noise.
"Igitur qui desiderat pacem, praeparet bellum." -Publius Flavius Vegetius Renatus
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
Re: AR15 Help
In Basic and my first unit we used the Atchisson Device, after that for the next 20 years it was with real 5.56 ammo.entropy wrote:That's why I (jokingly) mentioned the Atchisson Device. The Air Force has used them for Basic Training and qualifications. (so I've heard from several AF vets.) You wouldn't hear the spring shucking up and down the buffer tube with the Atchisson Device, because it has an internal recoil spring. How do I know this? Because Army ROTC used them also. First time I shot an M16(A1) was with .22's! And I got stuck cleaning them because I "liked guns".ffuries wrote:That's what everyone keeps telling me, I just never heard it/felt it when shooting the M16 in the AF. Retired in 2008 and I think I last fired the M16 in 2006.RazorBurn wrote:All of my buffers, including my Colt and BCM "H" buffers rattle. It's normal.
The noise, vibration was so noticeable it caught me by surprise. Best way to describe it is to take a fiberglass pole and hold it straight out in front of you, then have someone hit the end of it. That wobble is what it felt like, with the spring noise.Also how I ended up being the defacto ROTC Det. Armorer, and got stuck cleaning the 16's and 60's when we went camping er, on FTX's.
The Atchisson Device jammed almost every other round, that thing sucked, that and there was a metal and canvas thing we put over the ejection port to deflect the 22 shells.
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
Re: AR15 Help
They worked great in full auto, but yeah, jammed in semi regularly. we left the feed bags off 'em, we were shooting in the basement range of the Armory, and just swept them up.
"Igitur qui desiderat pacem, praeparet bellum." -Publius Flavius Vegetius Renatus
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
Murphy was an optimist.
A human being should be able to change a diaper, plan an
invasion, butcher a hog, design a building, conn a ship, write a
sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve an
equation, analyze a new problem, pitch manure, program a
computer, cook a tasty meal, fight efficiently, die gallantly.
Specialization is for insects - Robert A. Heinlien
- Junk Yard Dog
- Owner/Founder

- Posts: 48861
- Joined: Sat Aug 27, 2011 12:54 pm
- Location: New York
Re: AR15 Help
I bought one from Sarco back around '93, the miserable bastards never mentioned any of the devices shortcomings and that was before there was an internet to warn me. I unloaded that piece of shit fifteen years ago and at least made a small profit on it. Wouldn't work unless I soaked it in oil.
Leave it as it is. The ages have been at work on it and man can only mar it.
Don't hit at all if it is honorably possible to avoid hitting; but never hit soft.
Theodore Roosevelt
Don't hit at all if it is honorably possible to avoid hitting; but never hit soft.
Theodore Roosevelt
Re: AR15 Help
Made it hard to shoot expert when your rifle jams after every shot. I hated that thing with a passion.Junk Yard Dog wrote:I bought one from Sarco back around '93, the miserable bastards never mentioned any of the devices shortcomings and that was before there was an internet to warn me. I unloaded that piece of shit fifteen years ago and at least made a small profit on it. Wouldn't work unless I soaked it in oil.
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
Re: AR15 Help
So they were brass catchers, I thought they were deflectors. After 2 1/2 years of using the damn thing, I got stationed in Germany. First time I went to shot there I was in awe of shooting real 5.56 versus 22 ammo in the M16, the instructors laughed at my childless excitement. Never used it again and never had a desire to use it again.entropy wrote:They worked great in full auto, but yeah, jammed in semi regularly. we left the feed bags off 'em, we were shooting in the basement range of the Armory, and just swept them up.
It was a good ideal on paper, but a disaster in reality. I really have to wonder if the system ever worked correctly, or did it suck right out of the box?
Mike
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
TSgt, USAF Retired
Jan 86 - Sept 08
Aircrew Life Support
"Your Life Is Our Business"
(122X0, 1T1X1, 1P0X1)
NRA Life Member
Re: AR15 Help
JP Enterprises makes a self contained buffer system that gets rid of the feedback inside the tube... they include a spacer to work in rifle length tubes, and it allows you to remove the buffer retainer. Expensive, though. If I remember correctly, JP puts out a kit to adjust the spring tension/buffer weight).
I run it in my regularly shot AR, being I got it for a low price when it was released (wanted to try it out). Solves the feedback, especially with a .22 upper installed. But if you are paying full price for the kit, I'd have to say only do it if you really can't stand the noise. With the other three ARs I've built (one .45 D/I, one FDE 18", and I have a partially built lower that I'll finish when I leave NJ), all other ones use the standard buffer and spring. If it were cheaper, I may have tossed them in other rifles.
I run it in my regularly shot AR, being I got it for a low price when it was released (wanted to try it out). Solves the feedback, especially with a .22 upper installed. But if you are paying full price for the kit, I'd have to say only do it if you really can't stand the noise. With the other three ARs I've built (one .45 D/I, one FDE 18", and I have a partially built lower that I'll finish when I leave NJ), all other ones use the standard buffer and spring. If it were cheaper, I may have tossed them in other rifles.



