I'm looking to convert

[sjr87]

my A2 style AR to an M4 style upper. It is an armalite M15A2. I like everything about the rifle but the fixed handle. Can I purchase just a stripped M4 upper then swap it out with the A2 upper, or do I need to buy a complete M4 upper, barrel and all.

 

[jasons]

I think you would also need a barrel that has M4 feed ramps. You may be able to have your existing one modified though. I think everything else would fit.

http://www.m4carbine.net/showthread.php?t=193

 

[vellnueve]

Not all flat-top uppers have the M4 cuts. In fact, I'd say that most of them don't.

If you don't have the tools or the action block you might be better off just buying a complete upper.

 

[abomb60]

You can buy a stripped upper and install all the parts in it (forward assist & ejection port cover). Some companies "complete upper" will have a barrel, gas tube, delta ring & handguards. Other companies sell a complete upper with the forward assist & ejection port installed.

If you want to invest a little $$ and do the work yourself all you really need is an upper receiver action block & a barrel lug tool. Once you have those parts it's simple to rebarrel the upper.

1. Put upper in action block & tighten in vise
2. Install delta ring assembly to barrel
3. Insert barrel & torque to spec
4. Insert gas tube into front sight base & pin in place
5. Install handguards

Thats about it. You may need other parts if you're going from rifle length to carbine length. If you like I can help you out and show you how to do it if you want to drive up to NE Mass. I have all the tools & know-how and would be glad to show you how it's done.

 

[sjr87]

You can buy a stripped upper and install all the parts in it (forward assist & ejection port cover). Some companies "complete upper" will have a barrel, gas tube, delta ring & handguards. Other companies sell a complete upper with the forward assist & ejection port installed.

If you want to invest a little $$ and do the work yourself all you really need is an upper receiver action block & a barrel lug tool. Once you have those parts it's simple to rebarrel the upper.

1. Put upper in action block & tighten in vise
2. Install delta ring assembly to barrel
3. Insert barrel & torque to spec
4. Insert gas tube into front sight base & pin in place
5. Install handguards

Thats about it. You may need other parts if you're going from rifle length to carbine length. If you like I can help you out and show you how to do it if you want to drive up to NE Mass. I have all the tools & know-how and would be glad to show you how it's done.

Thanks man, I'm sure a friend of mine who is a member on the board could be bought for a beer or two to lend out the tools/know how since he built his. I would like to reuse everything from the rifle if possible, since that would save me the most $. I just want the flat top to run the eotech since I like their set up the best for optics.

 

[matt]

Not all flat-top uppers have the M4 cuts. In fact, I'd say that most of them don't.

If you don't have the tools or the action block you might be better off just buying a complete upper.

Are you saying buy one barrel and all? because swapping a barrel is super easy and for the price of a fully built upper you could buy the receiver and tools and have lots of ammo $$ left over easily.

Or you could go to someone who builds ar's and have them do the swap. It's easy. Remsport can supply you the upper and I'm sure they will install it for you reasonably.

 

[vellnueve]

Given the choice between buying a $200 barrel and a $350 complete upper, I'd go with the complete upper every time.