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+--- Thread: 6061 uppers? (/showthread.php?tid=6943)
6061 uppers? - Tedward - 12-24-2013
I have 5 DPMS Lo Pro Uppers and they are way more solid than any Milspec thin Upper I have them with Beowulfs, 24"Grendels and they have in the thousans of rounds with no issues and still so tight tight I have to use a punch to get the take down pins to slide out. Just like day one.
If reputable manufactures use it there is a reason or they would not continue to do so.
6061 uppers? - Ridgerider - 12-24-2013
500 Wrote:What about the carbon 15?
Injection molded plastic
6061 uppers? - Tedward - 12-25-2013
LRRPF52 Wrote:6061 Aluminum is a great alloy for certain climbing components, where the ductility of the alloy does well with loads and impact, like the weight of a climber falling and being stopped by connections.
The DPMS Claw receiver insert tool was meant for their Lo-pro Classic that came out back in the day, where they were able to source cheaper alloys, low-end components, and easier tool time to offer an AR15 for $630 retail. 6061 is easier to cut, being softer, and as mentioned, it's cheaper. They also got rid of the ejection port door, forward assist, and used a bull barrel that didn't require complex and timely profiling. Slap on a 6061 gas block, and call it good.
Anyway, the 6061 will flex more, so they are less likely to break, but will still distort under torque from the tool. If you true a thick 6061 upper, preferably with a tight extension tunnel, it can make a nice foundation for a heavy barrel or lighter gun, but impact resistance can be a different ball game, and if the anodizing isn't done deeply, I have seen a lot of flaking on them.
The benefit to 7075 T6 is that it has significantly more tensile strength than 6061, and in the AR15, receiver mate-up is better achieved with 7075 versus 6061, as the pivot pin and takedown pin lugs and bosses will wear faster with 6061. Where 6061 makes more sense is in the handguards, if using aluminum.
What I have experienced with a 6061 receiver set when using dynamic tension with a 2-point quick adjust sling is that a really nice, tight receiver fit has been worn loose. The 7075 T6 billet sets from top-end manufacturers are the ones to beat in this area.
As for Flex, hold a mil Spec Upper in your hand and squeeze it from side to side.. Watch it flex, I can do this with one hand and with my DPMS Low Profile, it will not budge. As for wearing out, I would like to see your worn out one, can you post that picture?
6061 uppers? - Ridgerider - 12-25-2013
Yes please I would like to see that as well so come on please lets see it.
6061 uppers? - Drifter - 12-25-2013
Tedward Wrote:As for wearing out, I would like to see your worn out one, can you post that picture?
I don't see where he said worn out; only where the fit between upper and lower wore loose in his application:
LRRPF52 Wrote:What I have experienced with a 6061 receiver set when using dynamic tension with a 2-point quick adjust sling is that a really nice, tight receiver fit has been worn loose.
You said yourself in this same thread that pin rub in a lower could result in wear:
Tedward Wrote:In a lower I think the Billet is more needed due to wear areas from trigger rub inside the lower...
I'm not sure why you feel that LRRPF52 must prove anything. His actual experience is in agreement with your speculation, and also with the data in links previously posted by you.
6061 uppers? - dmsims21 - 12-25-2013
According to the description on Midway, the DPMS Lo Pro is made of extruded 7029 T6.
I don't know the specifics, but it is probably closer in properties to 7075 than 6061.
6061 uppers? - Sputnik - 12-25-2013
Is it me, or do some posts seem confrontational and defiant? Don't take opinions so personal. Merry Christmas!
6061 uppers? - Tedward - 12-25-2013
Drifter Wrote:I don't see where he said worn out; only where the fit between upper and lower wore loose in his application:
You said yourself in this same thread that pin rub in a lower could result in wear:
I'm not sure why you feel that LRRPF52 must prove anything. His actual experience is in agreement with your speculation, and also with the data in links previously posted by you.
First Merry Christmas.
Nobody has to prove themselves but the topic was uppers and not the lower receivers. I am just referring to the uppers and yes I feel the billet Lowers, 7075, is better, more customizable by manufactures and that is what I was agreeing with.
As for uppers, I have not seen any wear in the take down pins on my DPMS Low Pro "Slick Sides". Now that dmsims21 stated they are not extruded form 6061, that one isn't in question then. The MI, as I stated earlier is 6061. I have a couple and would like to know if I should not use them in the future and is there is in fact reliability issues with them.
This topic started off on uppers and went into climbing components, back to 6061 receiver sets been worn loose between the tension pins. I don't even know of a lower made of 6061. MAG TECH might be and I have read of there supposed issues and will not use them or Carbon, plastic or any other composite parts. It might be ammo exploding but I want my receivers to contain the fragments in those situation. So I won't use them
Is 6061 Softer but thicker and might hold together under that situation of a catastrophic failure? If so I find that more appealing.
I have nothing to gain about my question as the topic asked, is the 6061 not reliable? I don't care about Climbing Gear, milling of softer or harder metals, just is it reliable or is there info on them failing.
6061 uppers? - Tedward - 12-25-2013
dmsims21 Wrote:According to the description on Midway, the DPMS Lo Pro is made of extruded 7029 T6.Found the exact material of the DPMS. 7031-T6 Extruded. Not sure of the strength but a null topic.
I don't know the specifics, but it is probably closer in properties to 7075 than 6061.
http://www.dpmsinc.com/Flattop-Lo-Pro-Upper-Receiver_p_253.html
6061 uppers? - Ridgerider - 12-25-2013
dmsims21 Wrote:According to the description on Midway, the DPMS Lo Pro is made of extruded 7029 T6.
I don't know the specifics, but it is probably closer in properties to 7075 than 6061.
Now I am really confused because when I searched Midway for the DPMS Low pro 4 listings came up 3 complete uppers and a lefty upper receiver all the upper descriptions state this "The Lo-Pro Upper Receiver is constructed of 6066-T6 aircraft aluminum and is of the "Slickside" variety," the upper receiver just says Product Information
Stripped upper receiver ready for a left hand build. Lo-Pro Flattop is streamlined and has no forward assist or dust cover. Stripped left hand bolt included. Now also on that page is What others have bought there is this Product Information
Shop more DPMS products This DPMS Low Profile Flat-Top AR-15 Stripped Upper Receiver is constructed of Extruded 7029 T6 Aluminum and given a Hard Coat Anodized Finish for durability.
So with that in mind are we really getting the truth from any manufacturer or distributor with the materials used in their construction. Or are they hedging their bets and covering themselves and use whatever material is available at the time. What I do know is this that any aluminum upper or lower whether it be 7076 6061 or 7029 it will be stronger than any injection molded plastic with a little bit of carbon added.
6061 uppers? - Tedward - 12-25-2013
Ridge Rider, good points. You are through in your search and none of Midways descriptions match DPMS's.
Who knows what you get but if it's a reputable company, I think it should be good to go.
6061 uppers? - NugginFutz - 12-26-2013
Sputnik Wrote:Is it me, or do some posts seem confrontational and defiant? Don't take opinions so personal. Merry Christmas!
Indeed - Merry Christmas, all! More EGGNOG!
6061 uppers? - 45r - 12-26-2013
The DPMS lo pro is a very tight fit.
I tried it on 2 lowers and it wasn't too hard to get the pins through.
No looseness at all.
It looked pretty good on my Mega lower.
I didn't see any tool marks and everything looks good quality.
For only 80 bucks it seems like a good deal.
6061 uppers? - Tedward - 12-26-2013
They Rock, Like I said I have several and without the brass deflector, none of my brass has dent's too.
6061 uppers? - heinz57grendel - 12-31-2013
Does anyone know what A/A uppers marked 6.5 gren. Are? 6061 or 7075. I don't see this upper on their website anymore.
6061 uppers? - jurassic - 12-31-2013
I would bet money they are 7075. I have never seen a 6061 upper, although I'm sure they are out there.
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heinz57grendel Wrote:Does anyone know what A/A uppers marked 6.5 gren. Are? 6061 or 7075. I don't see this upper on their website anymore.
6061 uppers? - 45r - 12-31-2013
Tedward Wrote:They Rock, Like I said I have several and without the brass deflector, none of my brass has dent's too.
What rail do you use with your lo pro.
Since they're thicker some rails don't fit.
6061 uppers? - Tedward - 01-01-2014
I'm using Nordic Components and any that have a barrel nut that locks to the upper and has a lock ring the barrel butts to. I happen to mill the back of the barrel nut to give it a different look but you don't have to. The black ring is the stop collar.
Check this out. http://nordiccomp.com/retail/shop/ar-15-10/nc-free-float-hand-guard-xl/
YHM also uses this type of Barrel Nut. If you use a Troy, you have to cut off a tiny anti rotation tab and I have done that for many models. Just make sure you tighten everything very tight. I have had no issue, it way stronger than any plastic HG so your definitely up one on that.
[ATTACH=CONFIG]4360[/ATTACH]
6061 uppers? - jurassic - 01-01-2014
Tedward Wrote:I'm using Nordic Components and any that have a barrel nut that locks to the upper and has a lock ring the barrel butts to. I happen to mill the back of the barrel nut to give it a different look but you don't have to. The black ring is the stop collar.
Check this out. http://nordiccomp.com/retail/shop/ar-15-10/nc-free-float-hand-guard-xl/
YHM also uses this type of Barrel Nut. If you use a Troy, you have to cut off a tiny anti rotation tab and I have done that for many models. Just make sure you tighten everything very tight. I have had no issue, it way stronger than any plastic HG so your definitely up one on that.
[ATTACH=CONFIG]4360[/ATTACH]
What wrench did you use to tighten the lock nut on your handguard. I cold not find a spanner wrench that fit it well. Nice looking rifle!
6061 uppers? - explorecaves - 01-01-2014
Tedward Wrote:I'm using Nordic Components and any that have a barrel nut that locks to the upper and has a lock ring the barrel butts to. I happen to mill the back of the barrel nut to give it a different look but you don't have to. The black ring is the stop collar.
Check this out. http://nordiccomp.com/retail/shop/ar-15-10/nc-free-float-hand-guard-xl/
YHM also uses this type of Barrel Nut. If you use a Troy, you have to cut off a tiny anti rotation tab and I have done that for many models. Just make sure you tighten everything very tight. I have had no issue, it way stronger than any plastic HG so your definitely up one on that.
[ATTACH=CONFIG]4360[/ATTACH]
How much material is left against the receiver face after you mill the barrel nut? Can you take a picture of the nut uninstalled?