I'm wanting to replace my Bushmaster A2 upper with an A3 flattop.  I would like to order a stripped flattop upper from Bushmaster and transfer the parts from my current Bushmaster A2 upper.  I looked in the FAQ here and did not see any discussion about stripped uppers.  Can anyone advise?

Thanks!

Go here Manuals & Downloads and download TM 9-1005-319-23. It will describe in detail how to disassemble every piece of your rifle!

Wouldn't it be cheaper if you bought a CMT complete upper for $95? You have to look around because some places sell for $120+ and some sell complete for $95.
Just a thought.

Good suggestion on the CMT complete upper.  I was hung up on the Bushmaster thing.  I'll check it out.

Also, thanks for the manual ref.

Dangerdan,

Where do I find a complete CMT upper (no barrel) for $95?  I found a STAG upper for $122 but I can't find this $95 deal.  I'm real interested.

CMT/STAG are the same. Look here: globaltactical.com/axami/shop.php?grd=153
Make sure you know what barrel you have to match an upper (i.e. If your using the barrel off your Bushie upper, then you need the CMT upper and NOT the CMT M4 upper. The M4 upper has M4 extentions and won't match your Bushie barrel which has standard rifle extentions.)

I think Denny is selling these for $95 shipped. Also check www.jtacsupply.com

Quoted: I'm wanting to replace my Bushmaster A2 upper with an A3 flattop.  I would like to order a stripped flattop upper from Bushmaster and transfer the parts from my current Bushmaster A2 upper.  I looked in the FAQ here and did not see any discussion about stripped uppers.  Can anyone advise? Thanks!

If you are asking HOW TO, then you missed FALARAKS tacked thread above.

AR-15 •  Build It Yourself •  Assemble your own LOWER, UPPER, FREE FLOAT, TRIGGER, GAS BLOCK - Step by step instructions!

Thanks for the info guys.  I think it will be CMT!

I got mine complete and with tmarks from jtacsupply for $95 shipped.

Disassembly Procedure For Upper Receiver

1. Remove forward assist assembly roll pin with a punch.

2. Remove forward assist and spring.

3. Remove the ejection port cover pin by removing the "C" clip and pull the pin to the rear.

4. Remove handguard halves by pulling rearward on the delta ring and pulling outward on the rear of each handguard.

5. Remove the gas tube by driving out its retaining roll pin using a 1/16" punch.

6. Place the upper receiver in an action block in a vise and remove the barrel nut/delta ring assembly.

7. Remove the barrel from the upper receiver with a pull and twist motion.


Reassembly Procedure For Upper Receiver

1. Put some moly lube on the barrel extension and insert the barrel into the upper receiver (which should be in an action block and vise), aligning the index pin of the barrel with the slot in the upper receiver.

2. Coat the barrel nut's threads with moly grease and thread it onto the receiver.

3. Torque the barrel nut to 30 ft. lbs. using an armorer's wrench and torque wrench. Apply additional torque (if necessary) to the barrel nut to provide adequate clearance for the gas tube to move through the barrel nut assembly.

4. Insert the gas tube into the front sight base assembly and pin it in place with the gas tube roll pin.

5. Install handguards by pulling rearward on the delta ring, placing the front of the handguard into the front cap and pushing inward on the rear of each handguard.

6. Replace the ejection port cover.

7. Push the rod halfway through the ejection port cover and spring.

8. Gently bend the open end of the spring up towards you, give it a twist to preload it, then press it back flat into place.

9. Push the ejection port cover pin the rest of the way through and install the "C" clip.

10. Insert the forward assist assembly and spring into the upper receiver.

11. Press the forward assist assembly into the upper receiver until the notch for the roll pin is aligned with the roll pin's hole.

12. Drive forward assist roll pin into place.