Problem with upper/lower fit.

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[ARCHIVED THREAD] - Problem with upper/lower fit.

Posted: 8/13/2005 9:10:45 AM EDT

I put my WOA upper receiver on my RRA lower to see how they fit. The front pin hinges with the receivers moving fine. However it is VERY difficult to get the upper receiver fully seated into the lower receiver. If I remove the front pin, the upper receiver easily slides horizontally into place. But with the the upper and lower hinged, it takes a great deal of force to push the upper down into place. I put grease on the parts, but with no effect. Should I do a little filing on the small square of metal on the upper receiver where the back hole is? Thank you.

Posted: 8/13/2005 9:33:13 AM EDT

[#1]

I had the same problem with my LAR upper on my RRA lower...overtime it just gradually fit snug instead of super tight, I reckon from me taking it apart and cleaning and just playing around with it.

Posted: 8/13/2005 1:55:35 PM EDT

[#2]

Little oil and a few light whacks from a rubber hammer fixed mine. 500 rounds later, problem is gone...

Posted: 8/14/2005 6:29:00 AM EDT

[#3]

RRA lowers have a very "tight" radius at the rear where the upper lug fits. In a couple of difficult fits, I have placed very slight bevels on the sides of the rear upper lug. Touch up with Alum Black and you will not notice it.
Don't grind/modify the lower !
It will wear in with use.

Posted: 8/14/2005 6:58:03 AM EDT

[#4]

+1

Posted: 8/14/2005 1:37:33 PM EDT

[#5]

I had to grind off the bottom of the upper receiver pin block to get a fit. Just use a file and take very little off at a time.

Posted: 8/15/2005 6:20:51 PM EDT

[#6]

Before doing anything drastic, I'd just lube both surfaces where contact is being made and repeatedly put it together and take it apart. And if it doesn't begin to go together easily after awhile or you dont want to wait. Then sand down the lug or the inside of the lower. I'm sure over time it will fit snug. Sometimes the finish makes the fit too tight and has to be worn down.

Posted: 8/15/2005 7:04:35 PM EDT

[#7]

Go shoot it. The more you shoot it, the more it will break in.

Posted: 8/15/2005 8:17:13 PM EDT

[#8]

Say i have esp n or something but i think RRA lowers are tight.

Posted: 8/16/2005 5:11:45 PM EDT

[#9]

Yea thats the nature of thr RRA lowers , they are nice and tight . Thats a good thing !

Posted: 8/16/2005 6:55:38 PM EDT

[#10]

Quoted:
Thats a good thing !

Tight means nothing. If anything, if it's too tight, it's not field servicable. It does nothing for the operation or accuracy of the weapon. It is simply a "feel good" attribute.

Posted: 8/16/2005 10:54:57 PM EDT

[#11]

My first RRA lower was tight (I think it is around ser# 032XXX) but the second one I bought is about perfect. I slapped a CMT upper on it and it has enough tension to stay put and not rattle, yet it is still VERY easy to take-down.

I'd say open and close them a few times, and if you think it is just fitting too tight to work, stop where you are and see what is holding you up.

WIZZO

Posted: 8/16/2005 11:35:08 PM EDT

[#12]

Had the same issue with my RRA lower, I slammed the right side of the weapon the the deck and low and behold the pins went right in. They will losen up over time.

Posted: 8/19/2005 5:18:55 PM EDT

[#13]

Upper/lower tightness not important? Bullshit. It's not everything, but it's a really big thing. What crackpot on this ignorance crater thought up that little bit of mythology?

The neat things about these forums is that ignorant assholes get to spread untruths, and if they hang around long enough, beat their chests and say the right things, people start believing their ignorant crap.

Of course, the next thing they'll try to say is that a good tight shooting posture does nothing for accuracy.

Posted: 8/19/2005 5:35:05 PM EDT

[#14]

Quoted:
Upper/lower tightness not important? Bullshit. It's not everything, but it's a really big thing. What crackpot on this ignorance crater thought up that little bit of mythology?

The neat things about these forums is that ignorant assholes get to spread untruths, and if they hang around long enough, beat their chests and say the right things, people start believing their ignorant crap.

Of course, the next thing they'll try to say is that a good tight shooting posture does nothing for accuracy.

Well since there are so many “ignorant assholes” here that spread “untruths” why don’t you tell us a little about your self?

Posted: 8/19/2005 6:59:21 PM EDT

[#15]

Quoted:
Upper/lower tightness not important? Bullshit. It's not everything, but it's a really big thing. What crackpot on this ignorance crater thought up that little bit of mythology?

The neat things about these forums is that ignorant assholes get to spread untruths, and if they hang around long enough, beat their chests and say the right things, people start believing their ignorant crap.

Of course, the next thing they'll try to say is that a good tight shooting posture does nothing for accuracy.

Posted: 8/21/2005 2:07:52 PM EDT

[#16]

3-4cav
Wow....there are better ways to get your point across...

A respectful disagreement is one thing....what you just spewed out was uncalled for.

Settle down big guy...hug.gif

Posted: 8/22/2005 9:29:01 AM EDT

[#17]

Quoted:
Upper/lower tightness not important? Bullshit. It's not everything, but it's a really big thing. What crackpot on this ignorance crater thought up that little bit of mythology?

The neat things about these forums is that ignorant assholes get to spread untruths, and if they hang around long enough, beat their chests and say the right things, people start believing their ignorant crap.

Of course, the next thing they'll try to say is that a good tight shooting posture does nothing for accuracy.

I'm one of the ignorant assholes who need to learn the truth.

Please explain what you mean by "it's a really big thing".

Posted: 8/22/2005 10:31:17 AM EDT

[#18]

I know some people here are hell bent on making this issue with fitment between some RRA lowers and some uppers a big thing and but in truth, it's just not.

You have already been giving good advice on how to resolve the issue and in the end you will have a very nice fitting AR. While a tight fit does not add anything useful in a practical sense, it does not subtract from anything either. This garbage about a tight fit somehow takes away from the AR's field serviceability is just that, garbage.

The only positive “purpose” of having a tight upper-to-lower fit is to minimize\eliminate any rattling in that area. Again, this has no effect on functionality or reliability but some of us hate AR’s that are rattle traps

That said...

Quoted:
Upper/lower tightness not important? Bullshit. It's not everything, but it's a really big thing. What crackpot on this ignorance crater thought up that little bit of mythology?

The neat things about these forums is that ignorant assholes get to spread untruths, and if they hang around long enough, beat their chests and say the right things, people start believing their ignorant crap.

Of course, the next thing they'll try to say is that a good tight shooting posture does nothing for accuracy.

I guess being flat out wrong wasn’t good enough for you because apparently you felt the need to make a complete ass out of yourself in the process too?

(Damn, and I thought I did a good job of making myself out as an asshole here some times but you have me beat by a mile!

So Einstein tell us, how does a tight upper-to-lower fit on a AR\M16 make the weapon any better in a functional or reliability stand point? I know you can’t but I’m curious to read what you come up with anyway?

Posted: 8/22/2005 1:43:15 PM EDT

[#19]

Patiently waiting for 3-4CAV to enlighten us "ignorant assholes" with an explanation on how tightness between the upper and lower will effect function / reliability of the AR15/M16 platform.

I have a feeling I am going to be waiting for a long time.

Posted: 8/22/2005 4:58:53 PM EDT

[#20]

Quoted:
I have a feeling I am going to be waiting for a long time.

I'm on day 3...........and counting.

Posted: 8/23/2005 4:58:30 AM EDT

[#21]

Sorry, I don't feel the itch to come to this ignorance crater very often, for some reason. To say that tightness does nothing for the accuracy of the weapon is something that is currently fashionable in this crowd of wannabe computer geeks.

I guess that proper shooting posture and sight picture is "not important" either.

For those of you with IQs that allow for reason, here is the deal. Your rifle's barrel flexes each time you shoot. Of course, the bullet travelling down the barrel for part of this time. The idea is to make it flex the same way every time. With a poor upper to lower fit, your barrel flexes DIFFERENTLY each time because of it's loose carriage and bad harmonics.

But I guess that all the benchrest shooters and long range competitive shooters must be wrong. This is not the first time you cretins all got together via the internet and decided what RIGHT was.

Posted: 8/23/2005 6:21:17 AM EDT

[#22]

Quoted:
Sorry, I don't feel the itch to come to this ignorance crater very often, for some reason.

Yea, but when your here you sure got the itch to insult the members don’t ya!

To say that tightness does nothing for the accuracy of the weapon is something that is currently fashionable in this crowd of wannabe computer geeks.

Wow, insult two. Like I mentioned in that other post regarding upper/lower fit: “If play between the upper and lower was that detrimental to accuracy don’t you think this “problem” would have been addressed some 30+ years ago? And why the hell would the Army be pulling old M16 receivers out of service to use as a base for SPR rifles?

I guess that proper shooting posture and sight picture is "not important" either.

Again, like I mentioned in that other post regarding upper/lower fit: If the shooter does his part, of which I believe I mentioned “shooting posture and sight picture”, the weapon will do it’s part.

For those of you with IQs that allow for reason, here is the deal. Your rifle's barrel flexes each time you shoot. Of course, the bullet travelling down the barrel for part of this time. The idea is to make it flex the same way every time. With a poor upper to lower fit, your barrel flexes DIFFERENTLY each time because of it's loose carriage and bad harmonics.

But I guess that all the benchrest shooters and long range competitive shooters must be wrong. This is not the first time you cretins all got together via the internet and decided what RIGHT was.

Again, if this was such a problem it would have been addressed earlier by the manufacture during development or even the military after acceptance of the weapon.
We’re not talking benchrest shooting or long range competitive shooting or the tips or tricks those guys use to maybe increase their groupings by .0003 MOA. Were talking about how very minimal if any the effect is of a loose receiver fit to the average builder or soldier.

Again, I can speak from military experience having been issued M16’s, M16A1’s and M16A2’s, the A2’s being the only weapon out of the bunch to have been issued new. Regardless of age or receiver fit I qualified expert each and every time.

Now, where did I put that August copy of “Computer Geek Magazine”?

The"other thread"

Posted: 8/23/2005 6:41:43 AM EDT

[#23]

Wow.........a Google search on the subject turned up another “Computer Geek” who thinks like me, and sad part is, he’s a competition shooter!

Many people are under the false impression that the slop between the upper and lower receiver on the AR15 affects accuracy. It does not. At least not in the manner in which you might think. You can put this one firmly into the realm of operator error. Guys think this makes a big difference and they shoot lousy accordingly. There have been many efforts to tighten up the receivers, but the accuracy gain is infinitesimally small for the effort. I once met a guy who would not open his rifle up for fear that it would not have the same zero when closed! He was going to attend a match and didn't want to upset the rifle after zeroing it. I almost busted out laughing at the poor sap as he was suffering under some seriously false impressions. And he was Manic about it! You can pop the AR receivers apart all day and nothing is going to change. Must I say it again? There is NO bedding to spoil! Back to the project.

The Wonderful AR15 Land of confusion or heaven on earth?

Posted: 8/23/2005 6:57:49 AM EDT

[#24]

You have got to be kidding! The lies........the internet geeks spewing lies!!!!! Help! Get me out of this “ignorance crater” quick!!!

But the lockup in the AR-15 is all in the bolt and barrel extension. The bolt locks into the extension, which has become a part of the barrel, and it's as if the bolt, cartridge and barrel are hanging in line, in space. Of course, everything else is still attached, but nothing else really has any positive influence. This is what makes it possible to put this upper on that lowerand get the same results on the target. Every time.

But the lockup in the AR-15 is all in the bolt and barrel extension. The bolt locks into the extension, which has become a part of the barrel, and it's as if the bolt, cartridge and barrel are hanging in line, in space.

The same “line” I make mention of in my illustration.

put this upper on that lower.......

no........what if that lower has a looser fit than lower #1? How can I then

.......get the same results on the target. Every time.

The Accurate AR

Posted: 8/23/2005 10:39:36 AM EDT

[#25]

Quoted:
Sorry, I don't feel the itch to come to this ignorance crater very often, for some reason. To say that tightness does nothing for the accuracy of the weapon is something that is currently fashionable in this crowd of wannabe computer geeks.

I guess that proper shooting posture and sight picture is "not important" either.

For those of you with IQs that allow for reason, here is the deal. Your rifle's barrel flexes each time you shoot. Of course, the bullet travelling down the barrel for part of this time. The idea is to make it flex the same way every time. With a poor upper to lower fit, your barrel flexes DIFFERENTLY each time because of it's loose carriage and bad harmonics.

But I guess that all the benchrest shooters and long range competitive shooters must be wrong. This is not the first time you cretins all got together via the internet and decided what RIGHT was.

I'll remember your expert opninion, and be in awe at my apparent luck and good fortune, next time I'm able to ding the Echo silhoutte every time from the 500 yd line with an old, loose, rattle trap M16.

Posted: 8/23/2005 6:06:50 PM EDT

[#26]

www.armalite.com/library/techNotes/tnote55.htm

Armalite TECHNICAL NOTE 55: RECEIVER TIGHTNESS

"There is an intuitive belief that a tight fit between the upper and lower receivers is essential to accuracy, and that loose fit is bad. Oddly enough, this is untrue.

"....normal forging and machining variations may result in a small amount of play between the receivers or slight side to side receiver mismatch. This is not a manufacturing defect and has no effect on accuracy.

"Conclusion. ArmaLite® rifles are produced to tighter-than-normal tolerances. Receivers will normally exhibit a certain amount of looseness. This is normal and will not affect accuracy. Shooters may reduce the movement by insertion of a small amount of material between the receivers to improve the feel of the rifle, but it won’t improve accuracy."

Go through the Tech Notes at Armalite.com, a wealth of information available there.

Posted: 8/23/2005 6:37:30 PM EDT

[#27]

Quoted:
www.armalite.com/library/techNotes/tnote55.htm

Armalite TECHNICAL NOTE 55: RECEIVER TIGHTNESS

"There is an intuitive belief that a tight fit between the upper and lower receivers is essential to accuracy, and that loose fit is bad. Oddly enough, this is untrue.

"....normal forging and machining variations may result in a small amount of play between the receivers or slight side to side receiver mismatch. This is not a manufacturing defect and has no effect on accuracy.

"Conclusion. ArmaLite® rifles are produced to tighter-than-normal tolerances. Receivers will normally exhibit a certain amount of looseness. This is normal and will not affect accuracy. Shooters may reduce the movement by insertion of a small amount of material between the receivers to improve the feel of the rifle, but it won’t improve accuracy."

Go through the Tech Notes at Armalite.com, a wealth of information available there.

Ahhhh....bullshit! What does Armalite know....they're just a "bunch of crackpots in this ignorance crater thinking up little bits of mythology!"

Posted: 8/23/2005 7:41:43 PM EDT

[#28]

Gee, you know, I was fully prepared to come on here and apologize for being a jerk. You see, I was posting on two identically entitled subject lines, and when I came back, I ASS-umed some helpful moderator had deleted my previously posted information, which was in a reasonable tone. This kind of pissed me off.

But, I was revved to get in your faces. You know why? The three other times I've posted what I thought was useful information, you jackasses jumped all over me, because it was "accepted knowledge" here that what I posted could not possibly be true.

Well, I guess you showed me. Especially the one who righteously commented about having shot "real M16A1s and A2s." I'm so freaking impressed I don't know what to do with myself.

Now I know that the magical AR15 has been sprinkled with Armalite's marketing fairy dust, and unlike any other firearm known to man, does not need to be bedded, and a loose upper to lower fit cannot possibly cause inaccuracy.

(Oh, btw, none of your ill-thought out arguments, or "facts" actually contradict the REAL FACT of bullets, barrels, recoil repeatability and harmonics.) When you get done with your orgasmic computer gang-bang, I'll be somewhere else where there is dispassionate thinking and learning going on.

And, oh, by the way, I've carried a REAL M16 for 23 years and counting. And I'm NOT impressed.

Posted: 8/23/2005 8:00:17 PM EDT

[#29]

Gee, you know, I was fully prepared to come on here and apologize for being a jerk. You see, I was posting on two identically entitled subject lines, and when I came back, I ASS-umed some helpful moderator had deleted my previously posted information, which was in a reasonable tone. This kind of pissed me off.

Huh?

(Oh, btw, none of your ill-thought out arguments, or "facts" actually contradict the REAL FACT of bullets, barrels, recoil repeatability and harmonics.) When you get done with your orgasmic computer gang-bang, I'll be somewhere else where there is dispassionate thinking and learning going on.

Well then Mr Expert. Please enlighten us as to the relationship between all these buzzwords you've picked up and how they are related to a loose upper to lower reciever fit and poor accuracy?

Posted: 8/23/2005 8:13:21 PM EDT

[#30]

Quoted:
Well, I guess you showed me. Especially the one who righteously commented about having shot "real M16A1s and A2s." I'm so freaking impressed I don't know what to do with myself.

Yea, guess that would be me!

“Righteously commented about having shot real M16A1s and A2s.", ohhh please dude your killing me!

Sorry I can speak from experience, sounds like you just can’t accept the fact that you’ve been proven wrong.

I'll be somewhere else where there is dispassionate thinking and learning going on.

Please, by all means, leave! It’s obvious we don’t need your trolling around here.

And, oh, by the way, I've carried a REAL M16 for 23 years and counting. And I'm NOT impressed.

Oooooooo, my turn to NOT be impressed!

Posted: 8/24/2005 4:11:06 AM EDT

[#31]

Quoted:
But, I was revved to get in your faces. You know why? The three other times I've posted what I thought was useful information, you jackasses jumped all over me, because it was "accepted knowledge" here that what I posted could not possibly be true.

I don't know what threads you are talking about but if they went anything like this, you probably deserved to be jumped on. Here's a thought, instead of simply telling us all how smart you are and how stupid we are, what don't you offer up some actual proof that backs up your claims? So far you have provided nothing but bullshit.

Quoted:
And, oh, by the way, I've carried a REAL M16 for 23 years and counting. And I'm NOT impressed.

You know what - I call

Nobody except a complete and total idiot could have carried a "REAL M16 for 23 years and counting"

and still have no idea how it operates. Reading your posts makes it hard for me to believe you've ever used or even seen the inside of an AR\M-16.

Really, you should do yourself a favor and just shut-up. You so wrong that's it's pathetic and the more you reply, the more ignorant you come across. If you do feel the need to ram your foot into your mouth a little deeper then I would love to read exactly how you "bed" an AR or how a loose upper to lower fit affects barrel harmonics?...

Quoted:
Now I know that the magical AR15 has been sprinkled with Armalite's marketing fairy dust, and unlike any other firearm known to man, does not need to be bedded, and a loose upper to lower fit cannot possibly cause inaccuracy.

Ignorant comments like that show you know nothing about the AR design. The fact that you are arguing your moronic view point so vehemently is what makes this so god damn

Posted: 8/24/2005 4:22:56 AM EDT

[#32]

Quoted:
I don't know what threads you are talking about....................

Right here.

Posted: 8/24/2005 6:38:09 AM EDT

[#33]

Quoted:
Quoted:
I don't know what threads you are talking about....................

Right here.

Oh ok, same BS, different thread. I did get a kick out of his "duct tape bedding" method

Posted: 8/25/2005 4:47:45 AM EDT

[#34]

I believe in the "O" ring. Two of my three need them to eliminate obvious wiggle.

I'm no expert, but the concept of Statistical Process Contol eliminates any need for "bedding" the upper to the lower. Terry's Laws of Chaos say there are too many variables to make any difference. Unless maybe the gun is locked in a vise bolted to a concrete piling

Posted: 8/25/2005 9:15:30 AM EDT

[#35]

Quoted:
RRA lowers have a very "tight" radius at the rear where the upper lug fits. In a couple of difficult fits, I have placed very slight bevels on the sides of the rear upper lug. Touch up with Alum Black and you will not notice it.
Don't grind/modify the lower !
It will wear in with use.

+1

My RRA upper/lower tight here also. I scraped a blade top to bottom along the rear corners of the rear lug, barely broke finish on these outer corners, and fit was made. Lower is untouched and needs now no wear to fit.

[ARCHIVED THREAD] - Problem with upper/lower fit.

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