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7/10/2003 10:37:57 AM EDT
I've got some complete A2 uppers.  They are nice, but I'd be happier if they were flattops.  I'm not too excited about doing the work myself.  What are my options for sending them away to be converted?
7/10/2003 10:57:35 AM EDT
[#1]
Cheaper and easier to just buy a flattop upper and swap them out.
7/10/2003 12:22:47 PM EDT
[#2]
DO YOUR EXISTING A2 UPPERS HAVE M4 FEED RAMPS OR NOT?

WITH M4 FEED RAMPS ON A BARREL EXTENSION, YOU NEED TO STICK WITH A RECEIVER WITH THEM, AS WELL.

WES
7/10/2003 12:28:47 PM EDT
[#3]
If you send your current uppers to Bushmaster and buy the flattop receivers from them, they'll do the labor for free (you pay shipping both ways).  You could then sell the A2 upper receivers on the EE to make up for some of the cost.

-Troy
7/10/2003 12:54:47 PM EDT
[#4]
Kind of showing my age here, but Bartholomew_Roberts hit it on the head... Back before there was such a thing as flat-top receivers, we used to have to make our own by cropping off the carry handle and machining a long block that saddled down over the top of the bald receiver (the rail was machined in this block) -- That block was attached using dev-con and set screws (I found the strongest method).

All-in-all, a rather mickey mouse way of doing things, but the only way at the time and excedingly more expensive than just buying a new upper...

I am sure that I have a picture of two of these old modified guns, they were not so pretty, but sort of cool from a nostalgic point?
7/10/2003 1:58:27 PM EDT
[#5]
by "convert" I mean to replace the A2 Upper reciever with a flattop unit, not attack it with a hacksaw.

Troy:
One is a BM upper and has the annoying extreme windage condition.  Maybe they will fix that by exchanging the uppers?

MSTN:
No, all of them are older uppers.  I don't think any of them have the extended feed ramps.
7/11/2003 10:14:11 PM EDT
[#6]
You can pick up a RRA flattop upper complete for $90.  That is of course if you don't mind swapping out barrels yourself, it isn't a big deal and is probably the cheapest way to do it.  I did it to mine and now have an extra A2 upper floating around that I don't know what to do with.
7/12/2003 5:53:00 AM EDT
[#7]
The annoying windage problem can be corrected by removing the barrel, cleaning and greasing the threads, and reinstalling to the right torque.  They get a little hamfisted sometimes and torque them too tight.

Same tools will let you swap the barrel to a different receiver:

Bench vice.

1/2" drive torque wrench (get the click type with about a 16" handle).

USGI M16 barrel wrench.

Barrel blocks or receiver blocks.  You're less likely to overtorque the barrel with the barrel blocks; the Army has few issues with this and uses the barrel blocks.

Roll pin punch (and something to hit it with) for the gas tube pin.

Copy of TM9-1005-319-23&P (available several places on line).

-- Chuck
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