What is the consensus on these polymer lowers? Are they a serious piece of equipment or more of a novelty? What are your thoughts.
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What is the consensus on these polymer lowers? Are they a serious piece of equipment or more of a novelty? What are your thoughts.
I would never use one personally.
I love them. I own three of them including prototype #6 (still running).
Way back when they first started I called them up and asked how the polymer stood up to arctic extreme cold. They were like we have no idea, we are in Arizona. So, I was like send me one and I'll try to break. I did, it didn;t, I still have it.
They are very very durable and ultralight and do not suffer from any of the problems that the other polymer lowers do.
A cav arms receiver has the grip and stock integrated to the receiver and its a fixed A1 length stock.
Other polymer lowers try to be more conventional and accept carbine tubes, but they frequently fail at that junction.
TED
A friend of mine put together a lower using one and a DD parts kit, and the parts seemed to fit normally, so it at least has that going for it...
I have one for a lightweight build, and no sign of wear after thousands of rounds:
http://i689.photobucket.com/albums/v...l/100_0620.jpg
It required some minor fitting during the build to get pmags to drop free, and has been flawless since then.
My first AR had a Cavarms MKII lower. Upper was an A2 with a Colt 20" A1 (1:12) barrel.
On the positive side, it was fairly ergonomic, it was ridiculously lightweight and it was reliable.
But it was not exactly a hard use rifle. I've since switched to LMT and BCM lowers and BCM uppers.
I have thought that a lightweight 16" middy barrel would be a nice compliment to one of these lowers though.
^^^^This.
Why?
No stock options.
No pistol grip options.
No trigger guard options.
No cost benefit.
Not proven in a hard use environment.
Why limit yourself? The modularity of an aluminum lower is hard to beat; make it your way, to your liking, not the manufacturer's.
If I were to build another rifle right now, I'd be looking at one of the newer ambi lowers.
I like mine a lot for specific uses. Otherwise, adjustable LOP is king. I have no worries about reliability nor durability of this lower.
Stolen from another site, after a Google search for "broken Cav Arms stock".
http://img.photobucket.com/albums/10...f/a4e1c41c.jpg
http://img213.imageshack.us/img213/2...armslower3.jpg
the rest of the story as to the top pic of the 2 posted above:
Quote:
Response from Cav Arms
I already discussed this with the customer, and he is sending it to us for a free replacement.
This customer was the first ever to successfully use a .45 ACP upper on one of our lowers for extended firing, after he had fabricated a magazine block for it.
I believe the problem lies in that a standard carbine buffer and spring were used with the upper. The violence of the action cycling beat the receiver apart. A heavier weight buffer and spring will be required for it to function correctly without damaging the lower. It is unfortunate that it happenned to him, but at least we now know this combination can create an unsafe condition and we will advise customers that a heavier buffer and spring are required for use with .45 ACP uppers.
Shade tree / ghetto gunsmithing.....
When I was trying to get off an A2 flash hider in order to get a low pro gas block on my go-to and training ARs, I was lacking in proper tools. I improvised with installing each upper on my CavArms lower and wedging said lower into my wife's elliptical machine and then wrenching on the the flash hiders. I put a great deal of stress on that stock but it held fine and I got the A2s off.
I have no concerns about the durability of my CavArms lower. I believe anyone else who had seen what I did would agree with me.
I was present when the CavArms rifle was run over as described here.
http://sinistralrifleman.com/2012/04...wer-receivers/
They're fine if you can do with fixed stock & grip.
I have 3 and have not had any issues with them with any upper I've used. I'm not at a high round count (maybe 1000 through one of them, 500 9mm on another). In a small amount of informal testing I did find that with a test upper it was more accurate with the Cav-15 lower than a regular lower. I've been curious how that would bear out in more testing or if it was an anomaly. I think they have a place but if I only had one lower it would be a standard one with a collapsable stock.