Starting an A2 build for AR number 4.  This one is going to be an M16 A2 clone or at least as close as I can get it.  So far I have a stripped Bushmaster A2 upper that I picked up used and a new Bushmaster stripped lower.  The upper does not have M4 feed ramps and I am planning on going with a Windham Weaponry 20" govt. profile barrel which has an M4 barrel extension.  Everything I've read say that that won't be problem.  

This is the plan for the build:
Upper
- Bushmaster stripped upper
- Windham Weaponry 20" Govt. Profile 1/7 barrel kit (barrel, FSP, A2 flash hider, delta ring, barrel nut, hand guard cap, gas tube, hand guards)
- Forward assist and dust cover probably from PSA or Windham Weaponry
- PSA no logo premium BCG
- PSA standard style ambidextrous charging handle

Lower
- Bushmaster stripped lower
- Bushmaster lower parts kit
- A2 pistol grip
- Standard trigger guard
- RRA A2 stock kit
- Ambi safety

So that's the plan, if I should change anything I'm open to suggestions.

Sounds nice.  Lack of feed ramps on the lower shouldn't be a problem.

The ambi safety would not be A2 spec, but I'm sure you know that.

OP, if you're a lefty who needs an ambi safety, you're aware you can go to Stag and build yourself a 2A instead of an A2, right?  

I think you possibly might mean upper.  But yeah, an A2 doesn't have M4 feedramps.  I don't think rifle barrels typically come with them.  But now that I think about it, do A4's?   I have no clue.  It was mainly a thing to enhance feeding on the M4, as I understand it.

Not to hijack the OP's thread but,  since we're talking about A2 upper receivers and M4 barrels, anyone see  a problem using an A2 upper with a 14.5 mid-gas ramped barrel on a lower with an A1 stock? Is the A2 receiver / M4 barrel combo generally not a problem, or is it only gtg when using longer barrels? TIA

I know a standard A2 would not have an ambi safety or an ambi charging handle but being a lefty I prefer to have those.  My other AR's are set up that way and I want to keep the controls similar on this build.  Besides the ambi controls I want it to look like a basic A2 rifle.

That should work fine.  The only ramp combination that can be a problem is a rifle ramped bbl & an upper w/ M4 cuts.

Finally pieced the build together, ended up using some different parts then what I initially listed.  I think it came out pretty nice.  I forgot how big a 20" barreled rifle with A2 stock is.  All of my other AR's are pinned 14.5's and 16's with SOPMOD stocks.  Here are the final specs:

Upper:
Bushmaster A2 stripped receiver with BCM forward assist and BCM dust cover
BCM gas tube
FNMI marked A2 govt profile barrel
PSA no logo BCG
A2 flash hider
USGI charging handle
Bushmaster A2 handguards

Lower:
Bushmaster XM15-E2S stripped lower receiver
PSA lower parts kit
RRA A2 stock kit
DTI ambi safety selector

Still need to take it to the range and test it out.

Looks good
Love the kiss rifles.
I built an A1 style frankengun.
Nothing fancy, just good times.

Needs moar M7.  Looks nice.  Post groups when you get 'em.

Nice Alpha Deuce OP  BTW, that the cleanest work-bench and neatest work area I've ever seen

Very nice! Now I know what to do with my extra stickers

Nice build. Always a fan of how well the rifles feel after handling carbines.