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1/27/2021 11:01:57 PM
1/27/2021 12:46:26 AM
Posted: 3/8/2005 7:42:30 PM EST
Is there have an assembly guide for CAV lowers?  I just picked up a new MKII lower with a parts kit and I wanted to try to put it together myself.
Thanks.
Link Posted: 3/8/2005 8:48:39 PM EST
It should have come with instructions... Anyways, the assembly is pretty much the same as a standard receiver  except for a few points.  

Since the receiver is molded plastic, you'll probably need to use and exactor or sharp utility knife to remove and flashing that may bind the parts.  Also, lighty spin a drill bit in every hole by hand to remove any burrs or loose plastic that may be hinding in the holes.  Be carefull not to actually drill into the holes or widen them.

There is a one inch long roll pin that comes with the receiver.  It is used to hold the buffer retainer in place.  After inserting the buffer retainer spring and retainer into the receiver at the opening of the buffer tube, you need to hold the retainer down while driving the roll pin in from the side.  You'll know what I mean when you see it.  

You obviously don't need the pivot/takedown pin detents or springs.  Save them, or do like I did and give them to someone who accidentaly shot a takedown detent across the room.

Now, there are two places where you might need to cut springs:  the bolt catch spring and selector detent spring.  I say might because some LPK spring may differ from others.  With my RRA LPK I had to cut 1 and 1/2 rings off the bolt catch spring before my bolt would lock open on an empty mag.  The same mags will lock the bolt on my Stag lower without modification to the bolt catch spring.  Since the roll pins are much easier to insert into a plastic receiver, I suggest clipping 1/2 a ring off at a time and testing with your upper and every mag you've got untill the bolt locks open reliably.  

With the selector spring, drop the spring thru the selector detent hole from the top.  The insturctions say to trim the spring so that it is flush with the selector hole.  Then you drop in the selector detent.  Finally, you insert the selector and use a punch/rod/anything to push the detent into the hole so the selector can get through.  Be warned, once you install the selector it will be very difficult if not impossible to remove.  Make sure you test fit every part in the receiver before installing it.  I hurried through the instructions and missed the part about trimming the selector spring.  I also forgot to test the selector in the selector hole.  I wound up with a very stiff safety.  Fortunately it lossened up after I flipped the selector back and forth while watching TV for an evening.

Little tip:  The easiest way to install the bolt catch roll pin is to tape up the jaws of some channel lock pliers or a set of vise grips.  Then just squeeze the pliers/grips to push the roll pin in flush.  To get the roll pin in just a little further, I used the same pliers and the extra takedown pin detent as a "punch" to push the roll pin just a little farther into the hole.

Hope I didn't miss anything.  What color did you get?

Link Posted: 3/8/2005 8:55:11 PM EST
Thanks man.  This will help tons.  
I bought a coyote colored one for my dissy project.  Armalite is selling them for $162 complete.  Can't beat the price.
Link Posted: 3/8/2005 10:16:25 PM EST

Quoted:
Thanks man.  This will help tons.  
I bought a coyote colored one for my dissy project.  Armalite is selling them for $162 complete.  Can't beat the price.

Is that with or without the lower parts kit?

BTW, the instructions are usually tucked away in the buttstock.
Link Posted: 3/9/2005 4:54:12 AM EST

Quoted:

Quoted:
Thanks man.  This will help tons.  
I bought a coyote colored one for my dissy project.  Armalite is selling them for $162 complete.  Can't beat the price.

Is that with or without the lower parts kit?

BTW, the instructions are usually tucked away in the buttstock.



Ahh, I didn't look.  Yeah $162 was with the parts kit.
Thanks.
cp
Link Posted: 3/9/2005 8:16:59 AM EST

Quoted:
Is that with or without the lower parts kit?



Cav MKII's are $95 stripped from Armalite, and the Brown and Green ones have AR15.com serial numbers.
Link Posted: 3/9/2005 4:07:00 PM EST
Got my Cav Arms MKII "AR15.COM SEBRXXX" OD Green Receiver from Armalite and am waiting for the LPK to come in.  Armalite told me the LPK's should in about a month from now.  I paid $162.00 + tax and NIC's check came out to $177.00.  The receiver looks nice and I already ran a drill bit by hand in all the holes, and now they look clean.  Looking to put a slab-sided upper receiver with a Bushmaster Super-Lightweight 16" barrel and a A2 Flash-hider.  Should be very light.

phxccw, where did you get yours from, I really don't like waiting another month to build this thing,
Do they have any more LPK's in stock?

1NavyChief-Ret
Link Posted: 3/9/2005 5:11:28 PM EST
Just get any LPK.  I used an RRA LPK.  Only 55 bucks and I had an A2 grip and the pivot/takedown pins and springs left over.  I saved them for a buddy that was building a regular lower.  He shot one of the detents into the floor heater vent and was very gratefull I had these parts.
Link Posted: 3/9/2005 5:29:03 PM EST

Quoted:
Got my Cav Arms MKII "AR15.COM SEBRXXX" OD Green Receiver from Armalite and am waiting for the LPK to come in.  Armalite told me the LPK's should in about a month from now.  I paid $162.00 + tax and NIC's check came out to $177.00.  The receiver looks nice and I already ran a drill bit by hand in all the holes, and now they look clean.  Looking to put a slab-sided upper receiver with a Bushmaster Super-Lightweight 16" barrel and a A2 Flash-hider.  Should be very light.

phxccw, where did you get yours from, I really don't like waiting another month to build this thing,
Do they have any more LPK's in stock?

1NavyChief-Ret



My FFL ordered it from Armalite last week and the LPK came from them too.  No delay here.  Sorry to hear that man, I hate waiting for parts.
Link Posted: 3/10/2005 4:31:06 AM EST

Quoted:
Looking to put a slab-sided upper receiver with a Bushmaster Super-Lightweight 16" barrel and a A2 Flash-hider.



Hope you don't mond waiting for a barrel, take a look here.  Most of us have been waiting since Dec.
Link Posted: 3/12/2005 9:44:00 AM EST
Is it just me or does the hammer pin look too short in the receiver?  It fits, it just looks to short while it's in place.
Link Posted: 3/14/2005 8:38:53 AM EST

Quoted:
Is it just me or does the hammer pin look too short in the receiver?  It fits, it just looks to short while it's in place.

The polymer lower needs to be thicker in some areas than an aluminum lower and a custom built hammer pin that was longer so that it fit flush on both sides would be more expensive and go against one of the basic reasons for using polymer instead of aluminum.
Link Posted: 3/14/2005 11:08:10 AM EST
Tag.

This post should be saved somewhere.....
Link Posted: 3/14/2005 12:16:03 PM EST

Quoted:

Quoted:
Is it just me or does the hammer pin look too short in the receiver?  It fits, it just looks to short while it's in place.

The polymer lower needs to be thicker in some areas than an aluminum lower and a custom built hammer pin that was longer so that it fit flush on both sides would be more expensive and go against one of the basic reasons for using polymer instead of aluminum.



So it's fine then if it doesn't fit flush???
Link Posted: 3/14/2005 4:30:44 PM EST

Quoted:

Quoted:

Quoted:
Is it just me or does the hammer pin look too short in the receiver?  It fits, it just looks to short while it's in place.

The polymer lower needs to be thicker in some areas than an aluminum lower and a custom built hammer pin that was longer so that it fit flush on both sides would be more expensive and go against one of the basic reasons for using polymer instead of aluminum.



So it's fine then if it doesn't fit flush???


It needs to be installed so that the j hook in the pin is snapped into the groove in teh middle of the pin so that it can't walk during firing.  There is no requirement anywhere for either of the pins to be flush with this or any other style of receiver.
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