Changing upper reciever on AR...can I do it??

25 December 2009, 23:19

I have decided to buy a flat-top upper reciever to replace my fixed carry-handle upper.

My question is, will I be able to do it myself or should I have a gunsmith do it?
I am reasonably handy, but I am wondering how difficult it is to remove the barrel from the old reciever and install it onto the flat-top.

Any advice?? How to do it, and what tools do I need??

Thanks!!

26 December 2009, 00:16

mstarling

You basically need three tools.

1) A way to hold the upper receiver ... usually a vise block made to fit around them ... so you can hold the piece while you take off the barrel and put it into the new upper.

2) A wrench to fit onto the receiver nut to loosen it on the original upper and to tighten the nut around the new barrel.

3) A punch to drive out the roll pin that holds the gas tube.

The process goes something like:

1) remove the hand guards
2) remove the roll pin holding the gas tube
3) remove the gas tube (you may harm it, so be prepared to replace it when you build the new upper)
4) remove the barrel
5) assemble the barrel in the new upper with nut and properly torque
6) replace the gas tube
7) replace the handguards

There are nice discussions of about every phase of AR-15 assembly here: http://www.ar15.com/forums/forum.html?b=3&f=4

Which will help a lot.

The answer is yes ... but there are a couple of tools you'll need.

Good luck!

26 December 2009, 01:41

DaMan

quote:
Originally posted by mstarling:
You basically need three tools.

1) A way to hold the upper receiver ... usually a vise block made to fit around them ... so you can hold the piece while you take off the barrel and put it into the new upper.

2) A wrench to fit onto the receiver nut to loosen it on the original upper and to tighten the nut around the new barrel.

3) A punch to drive out the roll pin that holds the gas tube.

The process goes something like:

1) remove the hand guards
2) remove the roll pin holding the gas tube
3) remove the gas tube (you may harm it, so be prepared to replace it when you build the new upper)
4) remove the barrel
5) assemble the barrel in the new upper with nut and properly torque
6) replace the gas tube
7) replace the handguards

There are nice discussions of about every phase of AR-15 assembly here: http://www.ar15.com/forums/forum.html?b=3&f=4

Which will help a lot.

The answer is yes ... but there are a couple of tools you'll need.

Good luck!

If you are buying a stripped upper, you'll want to remove the dust cover assbly. and the forward assist assbly. from your A2 upper and reinstall them on your flattop upper BEFORE you re-install the barrel.

If you want to remove the high front sight base, I'd recommend you replace it with a Picatinny gas block and free float hand guards.

Check out the instructional videos on Brownell's AR15 builder site.

26 December 2009, 02:00

DaMan

quote:
Originally posted by mstarling:
You basically need three tools.

1) A way to hold the upper receiver ... usually a vise block made to fit around them ... so you can hold the piece while you take off the barrel and put it into the new upper.

2) A wrench to fit onto the receiver nut to loosen it on the original upper and to tighten the nut around the new barrel.

3) A punch to drive out the roll pin that holds the gas tube.

The process goes something like:

1) remove the hand guards
2) remove the roll pin holding the gas tube
3) remove the gas tube (you may harm it, so be prepared to replace it when you build the new upper)
4) remove the barrel
5) assemble the barrel in the new upper with nut and properly torque
6) replace the gas tube
7) replace the handguards

There are nice discussions of about every phase of AR-15 assembly here: http://www.ar15.com/forums/forum.html?b=3&f=4

Which will help a lot.

The answer is yes ... but there are a couple of tools you'll need.

Good luck!