AR 10 parts

[volcmguy]

Im in the process of building my ar10 and i need a few parts. i need a forward assist assembly and a dust cover. where can i get these parts? ive looked everywhere with no luck.  also ive heard an ar15 forward assist will fit, is this true?

thanks for the help in advance

[98Z5V]

Ar-15 forward assist is the exact part you need - twins, for the two varients.  You can pick up all the parts from Brownells, Fulton Armory, or DPMS.  Brownells would be the fastest for shipping, with Fulton Armory close behind (prices would make the difference to me, on where of the two to buy from), and you might get the DPMS parts fast, or slow - and you won't get shipping or tracking info from them.  They're not bad, but you don't know how fast it'll be.  Consider that stuff in the purchase, otherwise, they're all alright.

[mrosbro]

dont think the dust cover will fit.to short?

[volcmguy]

thanks for the help.. i thought about taking the forward assist out of my ar 15 to see if it would fit but havent had the chance... after looking closer the pin that holds the forward assist in place on the ar10 looks like it would be long then the ar15 so would i need a different pin? and any other info on the dust cover? i cant seem to find anything

[98Z5V]

The dust cover on the .308 is larger/longer than the 5.56 version - that needs to be a .308-specific part that you order.  With that longer cover goes a longer pin/rod for the cover.  The dust cover spring is the same as the 5.56.  The forward assist assembly is the same as the 5.56.

When I installed my forward assist on my DPMS .308 upper, I found that the hole size for the rollpin was 0.080" (80-thou).  My punch sizes were 0.060" and 0.090", so neither would work properly to hold the forward assist in place, whilst I drove the pin in there (think, inserting something in there to hold the forward assist in it's position, while you tap in the rollpin).  What I found that worked perfectly was a 4d nail, 1 1/4" long.  It was a perfect fit into one side of the rollpin hole, held the forward assist assembly in place (under spring pressure), and I could tap the rollpin in there and capture the forward assist assembly for good. 

If that's confusing, I can explain it again.  Hell, I think I confused myself with what I've said...  :o

[volcmguy]

haha no i got it, thanks. where can i buy the dust cover, i couldnt find it on brownells

[imschur]

haha no i got it, thanks. where can i buy the dust cover, i couldnt find it on brownells

Thats a good question.

http://www.armalite.com/ItemForm.aspx?item=EA1165&Category=0db4d594-2661-45e9-b54d-c537311725f1

[mrraley]

The dust cover on the .308 is larger/longer than the 5.56 version - that needs to be a .308-specific part that you order.  With that longer cover goes a longer pin/rod for the cover.  The dust cover spring is the same as the 5.56. 

One quick note though... The AR10 has two (2) port door rod lengths.

The AR10T is 4 3/16" long when the regular AR10 is 4 1/8" long. It has to do with the barrel nut on the 10T and the delta ring on the regular 10.

[98Z5V]

That's good info, right there - on a safe assumption (I hate to do that...  ;D)  could we run the 4 1/8" rod on everything, considering it's still clipped into position?  Would that work on all .308 AR upper receivers?

[mrraley]

That's good info, right there - on a safe assumption (I hate to do that...  ;D)  could we run the 4 1/8" rod on everything, considering it's still clipped into position?  Would that work on all .308 AR upper receivers?

In short... no.

Now the reason behind that is:

1. there is no "C" clip on the AR10

2. The longer rod is because the "T" barrel nut is shorter. So the longer rod is needed to take up the space.

3. The way the AR10 is designed, your port door rod comes in from the front. There is no through hole on the other portion.

[98Z5V]

Aaaaah, got it - and thank you very much for the explanation.  Makes perfect sense.  You can clearly see my lack of detailed knowledge on the Armalite side of the house.    :o ;D  I was thinking it was like the DPMS-based part.  My fault, man... 

[mrraley]

No worries man.

That's why we are all on here and each person brings something different to the table to help the next person out.