Polymer lower? - Page 3
Firearm & Gun Forum - FireArmsTalk.com > Long Guns > Auto & Semi-Auto Discussion > AR-15 Discussion > Polymer lower?

Reply
 
LinkBack Thread Tools Display Modes
Old 02-07-2013, 12:02 PM   #21
Feedback Score: 0 reviews
 
70cuda383's Avatar
 
Join Date: Oct 2011
Location: Marysville,OH
Posts: 505
Liked 121 Times on 88 Posts

Default

Quote:
Originally Posted by GeneralPatton View Post
I've fired a poly lower gun before, it is no different than the aluminum lower besides it weighs a bit less.
yup. that was my experience. the only "shock" to the lower when firing is all in the buffer tube as the weapon cycles. and the buffer tube is a standard M4 metal tube, threaded into the receiver. I doubt that there will ever be enough force to strip out the threads for the tube, and if you look at it, the threads would strip out before the receiver would crack (from cycling)

so as long as you're only using it to shoot, and you don't do anything dumb with it, I see no reason why it will fail.
__________________
70cuda383 is offline  
 
Reply With Quote
Old 02-07-2013, 12:13 PM   #22
Feedback Score: 0 reviews
 
fsted2a's Avatar
 
Join Date: Apr 2008
Posts: 1,120
Liked 225 Times on 177 Posts
Likes Given: 321

Default

Quote:
Originally Posted by GeneralPatton View Post
I've fired a poly lower gun before, it is no different than the aluminum lower besides it weighs a bit less.
There are a few out there that are good quality; some not so much so. I had probably the worst end of the spectrum, and I feel more comfortable with aluminum. The aluminum receivers don't weigh that much anyway. The majority of the weight is in the barrel anyway.
__________________

"Democracy is two wolves and one sheep voting on what to have for dinner.
Liberty is the well-armed lamb contesting the vote." - Benjamin Franklin

fsted2a is offline  
 
Reply With Quote
Old 02-07-2013, 07:29 PM   #23
Feedback Score: 0 reviews
 
fsted2a's Avatar
 
Join Date: Apr 2008
Posts: 1,120
Liked 225 Times on 177 Posts
Likes Given: 321

Default

I have been told that a number of the mfr's of polymer/plastic/carbon fiber/whatever is not aluminum are using 3D printers to run off copies of AR lowers and uppers using ABS plastic, then some put a really thin layer of something over the outside to give it strength. They use a scanner to scan a milspec lower or upper, then let the machine make the copy. If that is so, if they have a low quality original, they are going to have a low quality copy.

__________________

"Democracy is two wolves and one sheep voting on what to have for dinner.
Liberty is the well-armed lamb contesting the vote." - Benjamin Franklin

fsted2a is offline  
 
Reply With Quote
Old 02-07-2013, 11:43 PM   #24
Feedback Score: 1 reviews
 
Join Date: Nov 2012
Posts: 1,036
Liked 100 Times on 83 Posts
Likes Given: 42

Default

Quote:
Originally Posted by fsted2a View Post
I have been told that a number of the mfr's of polymer/plastic/carbon fiber/whatever is not aluminum are using 3D printers to run off copies of AR lowers and uppers using ABS plastic, then some put a really thin layer of something over the outside to give it strength. They use a scanner to scan a milspec lower or upper, then let the machine make the copy. If that is so, if they have a low quality original, they are going to have a low quality copy.
I know the process you speak of, I've seen it done before. It's typically used to make a first prototype in full size and some are fairly durable. However I can't imagine anyone using them for anything beyond that, as the process to print them out is extraordinarily expensive and would far surpass the $100 or so bucks they get for them. There is a program, I think it's NASA using it, to create low weight polymer tools for use in space to save weight during liftoff. (I can't recall what the price was, but it was something stupid like a million dollars per pound to launch so they were trimming the fat on every corner) I don't recall it having been implemented yet though.

As for what a person owns, to each his own. I have always said people should shoot prior to buying and buy what they feel best with. I personally have now have both, and would carry either one comfortably. Now, as for that torture test that NFA has the links to; um, who the hell throws their AR 25 yards, or smashes their lower in a hydraulic press? Those aren't very realistic torture tests. If you want to prove something, shoot 10,000 rounds through it and let me see what it looks like thereafter.
__________________

A good plan executed today is better than a perfect plan executed at some indefinite point in the future.
- General George Patton Jr

GeneralPatton is offline  
 
Reply With Quote
Old 02-08-2013, 01:08 AM   #25
Feedback Score: 0 reviews
 
longunner's Avatar
 
Join Date: Jun 2012
Posts: 1,169
Liked 185 Times on 147 Posts
Likes Given: 106

Default

Quote:
Originally Posted by GeneralPatton

I know the process you speak of, I've seen it done before. It's typically used to make a first prototype in full size and some are fairly durable. However I can't imagine anyone using them for anything beyond that, as the process to print them out is extraordinarily expensive and would far surpass the $100 or so bucks they get for them. There is a program, I think it's NASA using it, to create low weight polymer tools for use in space to save weight during liftoff. (I can't recall what the price was, but it was something stupid like a million dollars per pound to launch so they were trimming the fat on every corner) I don't recall it having been implemented yet though.

As for what a person owns, to each his own. I have always said people should shoot prior to buying and buy what they feel best with. I personally have now have both, and would carry either one comfortably. Now, as for that torture test that NFA has the links to; um, who the hell throws their AR 25 yards, or smashes their lower in a hydraulic press? Those aren't very realistic torture tests. If you want to prove something, shoot 10,000 rounds through it and let me see what it looks like thereafter.
+1 wish I could like this stupid iOS app lol
__________________

Marlin Model 60
Mossberg Maverick 88-12 GA
Mosin Nagant 91/30
Stag Model 2
Savage Model 11
Saiga 7.62x39
Mossberg MVP Varmint
Chinese T53 Mosin Nagant X2

longunner is offline  
 
Reply With Quote
Old 02-08-2013, 01:39 AM   #26
Moderator
FTF_MODERATOR.png
Feedback Score: 0 reviews
 
JonM's Avatar
 
Join Date: Nov 2009
Location: Rochester WI,Rochester WI
Posts: 17,746
Liked 5797 Times on 3027 Posts
Likes Given: 397

Default

as cool an idea as 3d printers are you could take a pocket knife and a chunk of tool hardened steel and whittle the eintire rifle out by the time the printer is done with just one part. they are not fast enough for production volumes.

the weak spot on the ar15 lower is where the reciever and reciever extension meet together. its such a weak point that the real difference between the A1 lower and A2 lower is the reinforcement of the area. even with aluminum recievers its a weak point. if you have issues with a ar15 poly lower its always in the reciever extension tube area.

poly lowers do not hold up well to any sort of rough usage. as a range toy or a home defense application nothing wrong with em but i wouldnt use it for much more than that

__________________

"Gun control: The theory that a woman found dead in an alley, raped and strangled with her panty hose, is somehow morally superior to a woman explaining to police how her attacker got that fatal bullet wound." — L. Neil Smith

The problem with being stupid is you cannot simply decide to stop doing dumb things...

JonM is offline  
 
Reply With Quote
Old 02-08-2013, 01:48 AM   #27
Feedback Score: 1 reviews
 
Join Date: Nov 2012
Posts: 1,036
Liked 100 Times on 83 Posts
Likes Given: 42

Default

Quote:
Originally Posted by JonM View Post
poly lowers do not hold up well to any sort of rough usage. as a range toy or a home defense application nothing wrong with em but i wouldnt use it for much more than that
Now, what I want to see is how you came to that. Is this from something scientific or something you have seen or heard or just a theoretical opinion? And I ask that in all seriousness. I want to see one tested beyond abuse, but not some crackpot test that does things that no one would ever do in the first place.
__________________

A good plan executed today is better than a perfect plan executed at some indefinite point in the future.
- General George Patton Jr

GeneralPatton is offline  
 
Reply With Quote
Old 02-08-2013, 04:29 AM   #28
Feedback Score: 0 reviews
 
Quentin's Avatar
 
Join Date: Apr 2010
Location: Idaho
Posts: 6,592
Liked 1027 Times on 723 Posts
Likes Given: 1023

Default

Over the last couple years I've seen many pictures of cracked polymer lowers. Often snapped right off at the receiver extension.

I'd put up with a few more ounces to have 7075.

__________________

______
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together. You'll remember the quality of a gun long after you forget how much you paid for it.
________________________________________
US Army 1966-69, VFW Life Member, Retired Geek

Quentin is offline  
fsted2a Likes This 
Reply With Quote
Old 02-08-2013, 07:17 PM   #29
Feedback Score: 0 reviews
 
Join Date: Jan 2013
Location: Andrews In.
Posts: 46
Liked 11 Times on 11 Posts

Default

I just posted on this on another thread.... I have several of the old plumcrazy lowers and they have been drowned in salt water, dropped out of the back of my truck etc. Never has any of them failed in any way. Seen literally thousands of cheap Russian rounds, many of which had to be hammered out of the bore. Man I swear to you I OWN THEM , not just talking smak from my arm chair. These things are tough. You seriously cant break them

__________________
polyman69 is offline  
 
Reply With Quote
Old 02-08-2013, 07:28 PM   #30
Feedback Score: 0 reviews
 
Join Date: Jan 2013
Location: Andrews In.
Posts: 46
Liked 11 Times on 11 Posts

Default

Also buddy, the way they attach to the upper is crazy, tight as you know who's hat band, zero slack. The triggers (yes, they are poly too) are incredibly crisp, absolutely no creep. They also self lubricate, have no idea how, but I have never done anything other than wipenit down when I clean. Nothing sticks to these poly lowers. I guarantee you my 3 sons could destroy a steel ball with a rubber mallet and they have been dragging these guns offshore for years , uppers are rusted, hand guards all most completely gone, but the uppers still look brand new. I understand preference, my side arm 1911 only, but I dont call glock. Or xdm crap just because I dont like them.

__________________
polyman69 is offline  
 
Reply With Quote
Reply

Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Firearms Forum Replies Last Post
Polymer AR-15 lower bigrock44 AR-15 Discussion 45 05-22-2012 06:32 PM
Polymer AR Lower Shingles44 AR-15 Discussion 2 02-27-2009 05:48 PM