I’m at just under 4 lbs with optic and no poly parts, well, other than the grip. Coulda saved weight with aluminum take down pins too but wanted to use more durable titanium. Also didn’t want a polymer upper or lower either. I wanted all alloy, durable, reliable gun.
Yeah it would be!
I'm just aiming for under 5lbs with optic and loaded 10rd mag.
The cool thing is with ARs, I can build mine my way, you can build yours, and @swampratt (and everyone else) can build theirs. And there isn't *really* a wrong way. There are different levels of accuracy, reliability, longevity, cost, or whatever, but everyone can build one to whatever compromise of the factors they choose.
The best part is that as long as no one gets a stick up their butt, we can all still be friends.
Oh, almost forgot. The Vortex Venom that was in the classifieds is nearly mine now. It should come in the mail today.
For sure! I was just trying to show that you can get close to 3.5 lbs even staying all alloy!! The polymer lpk’s are certainly intriguing though.
And I appreciate the input.
The NFA poly LPK came in.
Weighed all the parts on my Dillon digital powder scale. I can provide a complete parts break down if anyone is interested
Total is 4.27oz for the LPK, including the 2.4oz A2 grip, but excluding a trigger guard (the NFA and most poly lowers include a molded in TG).
Without the LPK installed - I'm waiting for now since I ordered the TN Arms Co Hybrid poly lower today - and with the Vortex Venom and a loaded 10rd aluminum mag, it weighs 5lbs - 9.9oz.
Also ordered the AIM Surplus LW bcg over Black Friday.
Combining those three items, the total savings should be 8.66oz. That puts me just over 5lbs - 1oz loaded with optic!
Weighed all the parts on my Dillon digital powder scale. I can provide a complete parts break down if anyone is interested
Total is 4.27oz for the LPK, including the 2.4oz A2 grip, but excluding a trigger guard (the NFA and most poly lowers include a molded in TG).
Without the LPK installed - I'm waiting for now since I ordered the TN Arms Co Hybrid poly lower today - and with the Vortex Venom and a loaded 10rd aluminum mag, it weighs 5lbs - 9.9oz.
Also ordered the AIM Surplus LW bcg over Black Friday.
Combining those three items, the total savings should be 8.66oz. That puts me just over 5lbs - 1oz loaded with optic!
That’s cool. Now that you have the polymer LPK in hand, what do you think of the quality and expected reliability?
I was able to play with a friend's before I ordered mine (at the same time he ordered two more). Trigger is surprisingly better than expected, quality seems alright.
Assuming they went with a higher power hammer spring due to the *significantly* lower mass, I can't see a problem with ignition except for hard primers that give standard hammers grief if paired with lighter springs.
As far as the use of polymer, again assuming that the proper polymer was used; I have no issues with it here or in the lower.
Polymer is an amazing engineering material. What it lacks is the extreme strength and heat resistance of metals. What it gains is the light weight and elasticity. In the right application and when designed for the properties, polymer is superior to metal. Wear properties can be poor if not designed properly.
The only downside IMO to a poly lower is that the buffer system is a stressed functional part of the system. This has been addressed with some of newer "hybrid" poly lowers that are molded over a metal core where the buffer tube screws in that takes the eccentric load and transfers it back to the lower portion of the receiver. Otherwise, the lower receiver just holds the magazine and fire control group in relative position to the bolt carrier. The simple FCG of the AR-15 lends itself well to the properties of polymer. A bullpup or around the magazine (like pistols) design with linkages would not work as well - or would require some of the parts to be metal.
Would I want a poly AR-15 lower / lpk on a battle rifle? No. Certainly not for the lower receiver, due to the reason mentioned above. The LPK just because I haven't studied the engineering application well enough to know if the poly is a long term substitute for the original steel parts. It could very well be in the AR-15, and a cursory look at the properties of poly and the design of the parts leads me to think so. However I can't say that for sure.
This guy has been doing lightweight builds to the extreme. It's pretty amazing.
http://68forums.com/forums/showthre...for-a-3-0-pound-556-with-16-inch-Faxon-barrel
http://68forums.com/forums/showthre...for-a-3-0-pound-556-with-16-inch-Faxon-barrel
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Wow! Thanks for the link!
I assume you're a member there? I'm having difficulty registering. I have some comments/questions for him.
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