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View Full Version : I took the play out of my AR upper/lower for $1.09


Wicked K5
09-07-2010, 12:08 PM
I know it's just characteristic for a lot of ARs to have a little play between the upper/lower. Especially if the two are from different mfg's like mine. Well, for some reason, the slop just bugs me and wanted to come up with a cheap & simple remedy. While shopping with the wife at Michael's, I had an idea and it seems to snug up the fit real well.

here's the remedy:

9"x12"x~1.5mm adhesive backed sheet of black foam
http://i888.photobucket.com/albums/ac88/Wicked_K5/0906102020-00.jpg

two strips ~1.5" long x .125" wide along the lower receiver rail just above the pictograms and extending up the buffer tube extension
http://i888.photobucket.com/albums/ac88/Wicked_K5/0906102030-00.jpg
http://i888.photobucket.com/albums/ac88/Wicked_K5/0906102031-00.jpg

if you look real close, you can see the foam in between the two receivers- starting about the halfway point of the pictogram
http://i888.photobucket.com/albums/ac88/Wicked_K5/0906102025-00.jpg
http://i888.photobucket.com/albums/ac88/Wicked_K5/0906102021-00.jpg

vta
09-07-2010, 12:13 PM
ever heard of the accuwedge? $1 each at the gun show.

tomd1584
09-07-2010, 12:20 PM
If it helps put your mind at ease, then more power to you!

you realize by creating more tension between the upper and lower, you're going to eventually increase the wiggle/play between them in the long run, right?

unless you plan on keeping this tape on there forever, the play between them will get worse and worse.

Mssr. Eleganté
09-07-2010, 12:29 PM
...here's the remedy:

9"x12"x~1.5mm adhesive backed sheet of black tactical foam...

Fixed it for you. :p

Untamed1972
09-07-2010, 12:40 PM
Fixed it for you. :p


I think you meant 9"x12"x~1.5mm adhesive backed sheet of black tactical rifle receiver shim material.

LOL

Milsurp Collector
09-07-2010, 12:44 PM
If your camera has a macro setting (usually symbolized by a flower)

http://i90.photobucket.com/albums/k255/Bauer095/Picture1-17.png

using it will make your close-up pictures much sharper.

Wicked K5
09-07-2010, 12:53 PM
ever heard of the accuwedge? $1 each at the gun show.

I have. But, gun shows are usually 45 min. or more from my home + gas + cost to get in.

In regards to the accelerated wear issue, has there been solid proof showing that's what happens using a tension device? I would think that having a loose fit would be just as bad with the mating surfaces pounding each other every time the rifle is shot. And if these tension devices are in fact detrimental, all these lowers being sold with nylon "tension screws" are just a big gimmick and a negative one at that, right? I'm no expert, as this is my first AR build, so I'd like to hear everyone's thoughts on this subject:)

vta
09-07-2010, 12:57 PM
I have. But, gun shows are usually 45 min. or more from my home + gas + cost to get in.

but you know when its there you are going anyways ;)

mif_slim
09-07-2010, 1:02 PM
If your camera has a macro setting (usually symbolized by a flower)

http://i90.photobucket.com/albums/k255/Bauer095/Picture1-17.png

using it will make your close-up pictures much sharper.

Or take a picture of it at a longer distance and cut and crop to size. ;)

Wicked K5
09-07-2010, 1:43 PM
but you know when its there you are going anyways ;)

True. Sometime soon, I'll scrape enough money together to throw at the Miwal booth... then maybe get an accuwedge;)

Or take a picture of it at a longer distance and cut and crop to size. ;)

Sorry for the ghetto pics. They were taken with my phone. I think the only settings I can change are the flash

NiteQwill
09-07-2010, 2:15 PM
Every few weeks there's a thread that either:
a. Wants to address the play between the upper and the lower
b. Getting rid of the "sproing" sound when shooting an AR

Both a and b are normal. Fixing either a or b has no benefit but actually the opposite. Fixing a accelerates the "play" between the two receivers. Fixing b (usually by oiling/greasing the spring) introduces more crud into a system that already "just works."

Don't fix a or b.

Shoot it and be happy.

dieselpower
09-07-2010, 2:48 PM
Every few weeks there's a thread that either:
a. Wants to address the play between the upper and the lower
b. Getting rid of the "sproing" sound when shooting an AR

Both a and b are normal. Fixing either a or b has no benefit but actually the opposite. Fixing a accelerates the "play" between the two receivers. Fixing b (usually by oiling/greasing the spring) introduces more crud into a system that already "just works."

Don't fix a or b.

Shoot it and be happy.

I disagree with the fix for "a".

Explain it to me. Explain how a piece of tape creates enough force to weaken or deform the firearm. I agree it provide a slight amount of tension...only slight. There is no way, even in 50 years would this slight amount of force weaken the upper or lower. I could be wrong. Show me the science.

FTR, My Stag / Armalite combo had ZERO wiggle and required me to use a small brass hammer to first install the rear pin. I can now push it in with my thumb (disassembled several hundred times by now, 5 years). I still need a tool to remove the pin. It still doesnt wiggle, move, vibrate at all. Its not getting any worse after all this time. It took about a dozen pulls to loosen the pin up.

I believe in 10 years, the tape will need to be changed. It will have been crushed too thin to provide the force needed.

Even if by some weird fact of science, this tape does in fact deform the weapon. Simply increasing the thickness of the tape will solve this. I still imagine this will take a 10-20 years to occur.

Show me the science :)

b.faust
09-07-2010, 3:15 PM
b. Getting rid of the "sproing" sound when shooting an AR


Exactly ;)
See second quote: (by djleisure)

CHS
09-07-2010, 3:18 PM
Why are you "fixing" something that is explicitly designed into the specs of the rifle?

That wiggle is *SUPPOSED* to be there. It's by design.

Seriously, OCD and AR's just DO NOT mix.

rumblebee
09-07-2010, 3:26 PM
EZ fix for B...just remove the buffer tube and spring....walla, no more "sproing" sound....actually, your whole rig will be noise free :p:D

Every few weeks there's a thread that either:
a. Wants to address the play between the upper and the lower
b. Getting rid of the "sproing" sound when shooting an AR

Both a and b are normal. Fixing either a or b has no benefit but actually the opposite. Fixing a accelerates the "play" between the two receivers. Fixing b (usually by oiling/greasing the spring) introduces more crud into a system that already "just works."

Don't fix a or b.

Shoot it and be happy.

Josh3239
09-07-2010, 3:35 PM
Why are you "fixing" something that is explicitly designed into the specs of the rifle?

That wiggle is *SUPPOSED* to be there. It's by design.

Seriously, OCD and AR's just DO NOT mix.

:iagree:

b.faust
09-07-2010, 4:02 PM
That wiggle is *SUPPOSED* to be there. It's by design.



bdsmchs likes his AR's like he likes his ladies...with just a little wiggle.

:D

CHS
09-07-2010, 5:25 PM
bdsmchs likes his AR's like he likes his ladies...with just a little wiggle.

Who doesn't? :)

CSACANNONEER
09-07-2010, 5:32 PM
EZ fix for B...just remove the buffer tube and spring....walla, no more "sproing" sound....actually, your whole rig will be noise free :p:D

No spring or buffer in onee of my ARs but it still makes a "little" noise.

http://i125.photobucket.com/albums/p43/csacannoneer/056.jpg

I'm talking about the one in the rests, not the AR50.

JohnBrian
09-07-2010, 5:44 PM
Every few weeks there's a thread that either:
a. Wants to address the play between the upper and the lower
b. Getting rid of the "sproing" sound when shooting an AR
a. Mine was way too tight. I had to beat the pin out with a hammer & punch. Fixed it by removing some metal from the upper where it rests against the buffer hole. Still a little tight but I can push the pin out with a cartridge. It still has no wiggle.

b. I wouldn't know I was shooting an AR if I didn't hear the sproing!

Wicked K5
09-07-2010, 7:43 PM
I disagree with the fix for "a".

Explain it to me. Explain how a piece of tape creates enough force to weaken or deform the firearm. I agree it provide a slight amount of tension...only slight. There is no way, even in 50 years would this slight amount of force weaken the upper or lower. I could be wrong. Show me the science.

FTR, My Stag / Armalite combo had ZERO wiggle and required me to use a small brass hammer to first install the rear pin. I can now push it in with my thumb (disassembled several hundred times by now, 5 years). I still need a tool to remove the pin. It still doesnt wiggle, move, vibrate at all. Its not getting any worse after all this time. It took about a dozen pulls to loosen the pin up.

I believe in 10 years, the tape will need to be changed. It will have been crushed too thin to provide the force needed.

Even if by some weird fact of science, this tape does in fact deform the weapon. Simply increasing the thickness of the tape will solve this. I still imagine this will take a 10-20 years to occur.

Show me the science :)
:iagree:

Why are you "fixing" something that is explicitly designed into the specs of the rifle?

That wiggle is *SUPPOSED* to be there. It's by design.

Seriously, OCD and AR's just DO NOT mix.

It may be part of the the rifle's original design, but I'm not into the wiggle/wobble/play whatever. That's why I came up with my Foam AR Tacticool Shim:p All kidding aside, I really want to see proof that these wedges, tension screws, etc. will accelerate/increase the wear on the receivers. Or hear a better explanation backing up that theory.

Like I said before, I'm no expert gunsmith or MIT grad. I'm just a regular guy that sells motorcycle parts for a living. My take on the whole wiggle/no wiggle is actually the opposite of what most everyone is saying. Here's an argument I was thinking of earlier to dispell the wiggle is okay: Let's say I am going to install a crank assembly in my CR250. I have crank A and it has no play in the rod bearing. Then I also have crank B that has "a little play" in the bearing, but is "still within spec". Which crank would you rather have in there? Which one do you think will live a longer service life? That play in the rod and the bearing will only get worse and worse with each revolution of the crankshaft. Now the other part of my theory is this: whether there is little or no play, I think there are other parts that would wear out much faster than the upper/lower like BCG, trigger, barrel, etc. So the argument about wear on the receivers is kinda moot. I guess it just comes down to if you can live with/without the wiggle. Thanks for listening to my blah blah blah.

NiteQwill
09-07-2010, 8:34 PM
Keep your rifle nice and tight, it's yours.

But for one, Randall, the guru for the AR platform is pretty well respected and his word is trusted by many folks including those in the industry.

I can guarantee that if you use your rifle the way it was intended, things will start to wiggle everywhere. ;)

Take it for what it's worth. YMMV.

Happy shooting.


The drawback is that you cause both parts to have more wear when you fire them apart and slide the takedown pin in and out throughout the life of the rifle.
So using something to reduce wiggle actually causes MORE wiggle later on.

In-Spec uppers and lowers will wiggle.
When they fit tight, it's because they were not made right.

Slop between upper and lower is not a sign of low quality.
It's actually a sign of high quality because military guns are spec'd out to be sloppy.

CHS
09-07-2010, 8:50 PM
It may be part of the the rifle's original design, but I'm not into the wiggle/wobble/play whatever.

Then why on earth did you buy an AR?

tomd1584
09-07-2010, 8:57 PM
Then why on earth did you buy an AR?


Such an expensive, high quality piece of equipment shouldnt have any wiggle or play. that's a sign of a cheap product.
















:sleeping:

nick
09-07-2010, 9:03 PM
Doesn't Spikes have a tension screw? Is that a design flaw on their part, catering to the customers that has no value for the design, or good design?

NiteQwill
09-07-2010, 9:12 PM
Doesn't Spikes have a tension screw? Is that a design flaw on their part, catering to the customers that has no value for the design, or good design?

Nope, it's just catering to the market who wants it. Nothing wrong with that.

Almost as good as these sights, which are being sold every day to those who don't know any better ;)
http://www.knsprecisioninc.com/mm5/graphics/00000001/arhdduTH.jpg

or to those attempting to fix a problem that doesn't exist:

http://www.knsprecisioninc.com/mm5/graphics/00000001/nrthpgen2th.jpg

dieselpower
09-07-2010, 9:23 PM
Keep your rifle nice and tight, it's yours.

But for one, Randall, the guru for the AR platform is pretty well respected and his word is trusted by many folks including those in the industry.

I can guarantee that if you use your rifle the way it was intended, things will start to wiggle everywhere. ;)

Take it for what it's worth. YMMV.

Happy shooting.

Randall does know his stuff...on this issue I think its myth over fact.

I have held and shot several 1970's issued M16A1s and M16A2s. There was no wiggle. It is true I have shot M16A2s that wiggled..its annoying. The fact some wiggle and others don't is a huge clue here. Worn pins and worn holes. To state a worn old firearm is the same as a new firearm is a stretch.

I am sure when you have tolerance stacking, even a new firearm will wiggle some and would still be within mil-spec. That is not the same as tolerances that were near dead on. On tolerance stacking the other way the upper and lower are a PITA to push together and even requires sanding.

I also stand on good science that says, there is no way a slight pressure from tape is going to warp a steel pin or aluminum frame. There is a minium force required to cause warpage of metal...this isnt it.

All I know is this. After 5 years, close to 35K rounds, and over 50K in .22lr, which required opening the AR15 to swap the bolts dozens of times, I still have no wiggle. If in 5 years I have to add some tape due to worn pin holes, fine I understand that. Recoil does wear holes out.

DREADNOUGHT78
09-07-2010, 9:36 PM
I for one can't stand when the lower and upper have to much play. I will change out upper receivers till I find the one that fits the lower. It's my rifle and that is the way I like it. But on the other hand I don't like it when you have to beat the T.D. pins with a hammer to get them out. It is your rifle do as you please.

DREADNOUGHT78
09-07-2010, 9:37 PM
Nope, it's just catering to the market who wants it. Nothing wrong with that.

Almost as good as these sights, which are being sold every day to those who don't know any better ;)
http://www.knsprecisioninc.com/mm5/graphics/00000001/arhdduTH.jpg

or to those attempting to fix a problem that doesn't exist:

http://www.knsprecisioninc.com/mm5/graphics/00000001/nrthpgen2th.jpg

What if it is a self made problem? I have a friend whos pins fell out of his 80% lower often so he bought trigger pins problem solved....

NiteQwill
09-07-2010, 9:40 PM
What if it is a self made problem? I have a friend whos pins fell out of his 80% lower often so he bought trigger pins problem solved....

Then the product works as advertised. Or for FA weapons.

Properly mil-spec receivers and parts shouldn't need "anti-rotation" pins.

tonelar
09-07-2010, 10:01 PM
what would you say to a customer who wanted you to tighten their motorcycle drive chain to the point where it wouldn't have ANY slack?

Wicked K5
09-08-2010, 9:10 AM
Then why on earth did you buy an AR?
Honestly, 1)get it while I can still get it, 2)modularity, 3)it's as American as apple pie.


what would you say to a customer who wanted you to tighten their motorcycle drive chain to the point where it wouldn't have ANY slack?
Not gonna happen. Our shop would adjust the chain slack to within factory specs. If customer wants it tighter or looser he/she will do that on their own. To loose, the chain & sprockets would wear quickly and possibly jump teeth and/or derail. If too tight, wear would also be accelerated if the bike would even roll. And we know this for FACT with plenty of evidence to back that up. So far, I have yet to see uppers/lowers prematurely worn out due to a snug fit or too much tension between the two receivers.

a308garand
09-08-2010, 9:38 AM
The wiggle between the upper and lower is present in various forms in many different rifles. Some guys have rifles that need to be hit so as to shotgun open,,,just depends on how your parts fit or if the maker (like LaRue or even Rock River) purposely make the fit tight.

The wedge under your rear lug will provide tension until the day it is compressed and no longer works, then you swap it out for a fresh piece. Cleaning solvents and vibration can act together to help breakdown the wedge materiel....sometimes it breaks and the little bits travel into the trigger group- causing the rifle to malfuntion. Sometimes its a frozen trigger, safety will not turn easily, or maybe the disconnector gets blocked from catching the hammer. All not cool.

The US Army Marksmanship unit found that the upper/lower wiggle did not effect accuracy. The front and rear sights are both on the upper, so no change in sighting. I believe them, so no gain in accuracy by wedge under the lug.

I have not seen an upper receiver pushed out of alignment (by adding a wedge) with its relationship to the lower or buffer assembly,,,but I guess it could happen if its bad enough. Could it beat up the buffer and receiver extension? I don't know, but not going to risk it on my rifles.

This is a long way of saying, use the wedge if it suits your fancy. Just watch to see it doesn't get into the receiver and cause problems. It is your rifle to enjoy so get out and shoot it :)

dfletcher
09-08-2010, 11:37 AM
Why are you "fixing" something that is explicitly designed into the specs of the rifle?

That wiggle is *SUPPOSED* to be there. It's by design.

Seriously, OCD and AR's just DO NOT mix.

I glass bed my AR upper to a particular receiver. I glass bed my AR upper to a particular receiver. I glass bed my AR upper to a particular receiver.

I typed that three times, right? I typed that three times, right?
I typed that three times, right?

:TFH::TFH::TFH:

dieselpower
09-08-2010, 12:39 PM
The US Army Marksmanship unit found that the upper/lower wiggle did not effect accuracy. The front and rear sights are both on the upper, so no change in sighting. I believe them, so no gain in accuracy by wedge under the lug.


I think they just stated it doesnt matter because both sights are on the upper, WHEN USING THE IRON SIGHTS. In real use, the extreme wiggle will force a shift in a magnified optic causing parallax. Parallax is caused by your eye being off center with the optic, which is centered on the bore. AR15 magnified optics have a long eye relief which adds to this parallax, since the farther your eye is from the optic the less you will notice off center viewing of the image.

McGriff
09-08-2010, 1:24 PM
Put an earplug in there and call it a day. Then, after a week, you realize how rediculous it is to worry about the play between the receivers.

This is like the glock - connector. First thing you put in, first thing you take out.

McGriff
09-08-2010, 1:30 PM
AR15 magnified optics have a long eye relief which adds to this parallax, since the farther your eye is from the optic the less you will notice off center viewing of the image.

The further your eye is from the optic, the less of an angle the movement will create. If you are right up on the scope, and move the same distance sideways, it creates a more dramatic effect. Following? :D

I'm not disputing your statement, in fact I agree with it. BUT unless we are talking about bench rested shooting with serious accuracy, that is going to be hard to quantify.

viras
09-08-2010, 2:57 PM
I read the whole thread and no one answered this question:

What is the intended purpose of the "play" or "wiggle" between the upper and lower receiver? Why was it designed this way?

Randall's quote "military guns are spec'd out to be sloppy" is the best clue I could find, which leads me to believe that this play/wiggle was intended so that any lower can be switched with any upper (in the field) with minimal tools in a minimal amount of time. That's my best guess...

For example, with the wiggle/play, it would be easier to switch out a 16" upper to a 20" upper very quickly with just your fingernail popping out the takedown pins. On the other hand, if there was no wiggle/play, it would require a tool (bullet tip, punch, etc) to remove the rear takedown pin because there would be more tension between the upper and lower receivers, making it difficult to quickly switch uppers.

When I first built my AR-15 and AR-10, I was really concerned by this wiggle/play. I ended up getting an accuwedge and was really happy at first, until the next time I needed to clean my guns... then I found out how hard it was to pop out the takedown pins... Needless to say, I decided to remove the accuwedge immediately.

CHS
09-08-2010, 3:17 PM
I read the whole thread and no one answered this question:

What is the intended purpose of the "play" or "wiggle" between the upper and lower receiver? Why was it designed this way?



So that these firearms can be serviced and operated by 18 year old kids who have no prior experience with firearms in a jungle or desert environment with no tools other than the ammunition they are carrying.

freonr22
09-08-2010, 3:38 PM
I thought it was clearance to let the sand/mud/water through and out

darkest2000
09-08-2010, 3:44 PM
You've just successfully widened the gap between the upper and lower to it's maximum, permanently.

Only fix something if it's broken.

dieselpower
09-08-2010, 3:56 PM
You've just successfully widened the gap between the upper and lower to it's maximum, permanently.

Only fix something if it's broken.


wut?

1) Does installing a FDE stock break it? How about installing a quad rail...is it breaking it?

2) how is tape that provides tension between an upper and lower increasing a gap to its maximum..peranently.

Maybe you should read what we are talking about first.

darkest2000
09-08-2010, 4:02 PM
I disagree with the fix for "a".

Explain it to me. Explain how a piece of tape creates enough force to weaken or deform the firearm. I agree it provide a slight amount of tension...only slight. There is no way, even in 50 years would this slight amount of force weaken the upper or lower. I could be wrong. Show me the science.

FTR, My Stag / Armalite combo had ZERO wiggle and required me to use a small brass hammer to first install the rear pin. I can now push it in with my thumb (disassembled several hundred times by now, 5 years). I still need a tool to remove the pin. It still doesnt wiggle, move, vibrate at all. Its not getting any worse after all this time. It took about a dozen pulls to loosen the pin up.

I believe in 10 years, the tape will need to be changed. It will have been crushed too thin to provide the force needed.

Even if by some weird fact of science, this tape does in fact deform the weapon. Simply increasing the thickness of the tape will solve this. I still imagine this will take a 10-20 years to occur.

Show me the science :)
Well by adding the tape, you've now created an uneven tension that constantly pushes upwards, so you're forcing the wear pattern to concentrate only in one particular direction, thus creating an oval eventually.

And when that happens you'll find yourself adding more tape to compensate, (widening the gap in the process mind you), and in theory the cycle repeats until the hole is so out of spec it's not shootable.

Where as the same rifle, if left alone, will generate a uniform wear (break in) and once that's done the wear just stops.

I for one will shy away from buying an used AR if I knew the previous owner used any "tightening" devices.

Sure you might not see the affect for decades. Then again lung cancer doesn't happen overnight after you try the first cigarette either, why mess with it?

darkest2000
09-08-2010, 4:03 PM
wut?

2) how is tape that provides tension between an upper and lower increasing a gap to its maximum..peranently.

Maybe you should read what we are talking about first.

Ok, maybe permanent wasn't a good choice of word.

How about this: Because now the upper and lower are being pushed away from eachother, constantly.

CrippledPidgeon
09-08-2010, 6:57 PM
or to those attempting to fix a problem that doesn't exist:

http://www.knsprecisioninc.com/mm5/graphics/00000001/nrthpgen2th.jpg

Putting those in a brand-new properly spec'd receiver is kinda superfluous. I originally had an RRA NM trigger on my gun, and the pins used there are oversized. When I replaced the trigger with a geissele, I had way too much play due to the accelerated wear on the holes, so I used a set of KNS pins to keep everything in place.

dieselpower
09-09-2010, 12:00 AM
Well by adding the tape, you've now created an uneven tension that constantly pushes upwards, so you're forcing the wear pattern to concentrate only in one particular direction, thus creating an oval eventually.

And when that happens you'll find yourself adding more tape to compensate, (widening the gap in the process mind you), and in theory the cycle repeats until the hole is so out of spec it's not shootable.

Where as the same rifle, if left alone, will generate a uniform wear (break in) and once that's done the wear just stops.

I for one will shy away from buying an used AR if I knew the previous owner used any "tightening" devices.

Sure you might not see the affect for decades. Then again lung cancer doesn't happen overnight after you try the first cigarette either, why mess with it?


No. Recoil will cause wear in the same place. The slight upward pressure, keeping the two halves from wobbling is nowhere near what it would take to warp the metal. Without recoil in the picture, that tension will be there forever. The only thing that will alter that is corrosion.

I can prove this something we all see everyday. Your car hood. there is several hundred pounds of force constantly pushing up on it by a spring. Does it get weaker with time? No. it remains the same forever. Why? because the load is not enough to effect the strength of the metal. That force must overcome the molecular bonds in the metal itself. When you do that, time is then needed. the more pressure the less time. If I exceed the pressure by a huge amount, I will warp, bend or break the metal within small amount of time. If I only exceed the strength of the metal by a small amount, I must hold that pressure for a long time to warp the metal. the pressure of tape or accuwedge or an ear plug isn't even close to what is required to warp a steel pin or aluminum receivers, and even if it does you are looking at dozens of years..dozens as in 50+ years.

when you have movement you have wear. if you stop that movement you decrease the wear.

I did not want to flame anyone, I was hoping someone else would bring this up, but the exact opposite is true from what people are saying. truth be told, science tells us with 100% accuracy a wobbling ar15 will wear quicker then one with no wobble or even one where the wobble is stopped by tape.

When you have two parts that are not in tight with each other, the movement causes wear...thats a fact. You tighten them up you decrease the wear.

The recoil forces the upper to slam back. If the pin holes are loose, that rearward force becomes a hammer tapping on the lower. Its slight..it takes 1000s of rounds, but it will wear the holes larger.

Now take a upper and lower that are tight together, there is very little movement between the upper and lower at the pin holes. there is less or no hammering..less or no hammer = less or no wear. More of the recoil is efficiently transmitted since the attachment points are tight.