I'm looking to get a custom upper for my pre-ban soon. I want to get it made in one shot by one company so I don't have to mess around with ordering parts from different places.

The (2) companies I've seen mentioned on the boards most often are MSTN and CMMG. Are there others I should check into?

I would want this upper to be good for general purpose use (CQB to 300m). That being said, here's what I'm looking for in an A3 upper:

- 16" 4150 steel 1/9 (maybe 1/7) chrome lined bbl.
- Phantom flash suppressor
- Chrome-lined 5.56 chamber w/M4 feed ramp
- Chrome lined bolt carrier and bolt
- PRI Gas Buster Charging Handle
- Forged front sight
- ARMS #40 BUIS
- KAC FF RAS
- KAC RAS swivel sling mount

BTW< I'll be mounting my TA-31 and EO Tech 552 (maybe an Aimpoint) on it.

I've been kicking around the idea of getting an upper a 14.5" bbl (w/permanently attached Phantom) and a 20" bbl also with a permanently attached Phantom. I've looked at the velocity differences between the 14.5", 16" and 20" bbls and, if I'm only going to get one upper, I definitely want a 16" bbl. The 14.5" just loses a bit too much MV for me to be the only upper I have. Also, the extra 1.25" (or so) that a flash hider would add to a 16" bbl. is that big a deal. Please note I'm Illinois right now so I cannot have an SBR.

I'd appreciate any advice anyone has on this. I would only like to get one upper so I want to do it right this time.

I was wondering why you would permanently attached a Phantom to a 20" barrel?  You don't need it there to make length.  I would just thread it on with a crush washer under it.

For the barrel I would go with a bushy heavy barrel then have it turned to 0.850" under the handguards like the new Heavy M4 barrels. 14.5" or 16" is your preference.  Nice thing about the 16" is the extra MV and you don't have to do a permanently attached muzzle device.  You could put a QD for a suppresser or something like that on it.

It sounds like you are going to build something I have been thinking about for a while.  I have a heavy bushmaster sitting in my reloading room that is going to be sent off to be turned down.  The rest is still in the works.

IDHunt

That was a typo. I did't mean to say that.



Excuse my ignorance here, but why not just get a heavy M-4 barrel, assuming they're available.



Since I'm in Illinois (at least for the time being), I can have a suppressor. I've already got a 16" post-ban upper so I may just go for a 14.5" (with flash suppressor permanently attached) and a 20" upper but, as I said in first post, I'm still undecided on that part of the equation.

From what I have seen the Heavy M4 barrels are not too plentiful and when they are found they are overpriced.  I also don't see the need for a step down for an M203 if one is not going to be mounted.  Any steps in the barrel mess with the harmonics.  Reducing them will give you an inherently more accurate barrel.

IDHunt

BTT. Bueller? Anyone?

I'm leaning towards MSTN but, since I'm considering getting a mid-length KAC FF RAS, I'm a little weary because of their price on it. They have it on their website for $450 is is about $120 more than I've seen it at other places for.

I'm giving them the benefit of the doubt because it could be a typo or they could have been a price increase recently. The full length KAC FF RAS is $50 [b]LESS[/b] than the mid length but stranger things have happened. BTW, I'm all for paying a little extra for excellent service (which I believe MSTN has, both from my experience with my one purchase from them and from everything I've seen on the boards about them) but $120 more is bit much.

On a side note, has anyone ever ordered or tried to order an upper from Bushmaster with a KAC RAS? I know they don't list them on their website but I figured, if they would be willing to install it, I could just buy it and send it to them.

Yes the full length KAC FF RAS is less expensive than midlength due to the rarity of the mid length FF RAS.

I was wondering how often you think you will need to shoot people beyond 100-150m with your rifle in a defensive scenario?  I just dont see why a 16" barrel makes that big a deal for a civilian even in a total SHTF scenario.  Also both a 16" and 14.5" barrel will not fragment at 300m and will not have significantly different wound profiles.

If you must go 16" forged front sight with 1/7 twist thats a Colt barrel only.  Twice as expensive as a DPMS (which has not forged front sight).  Also why the forged front sight if you want a midlength FF RAS?  You cant keep the FSB with that tube.

My suggestion is you call MSTN and discuss your upper with them.  Building your upper is cheaper but you have to be willing to shop around for the best parts and the best prices.  Then you end up with exactly what you want.  MSTN does almost all Colt but I believe they have done some Bushmaster uppers.  However they are not a machine shop so they cant cut in the feed ramps for a Bushmaster for you so your back to Colt again.

My suggestion is what I selected, but of course I am biased (though I got the best prices)

Bushmaster 14.5" M4 1/7 twist 4150 barrel with forged front sight base.
Bushmaster flat top upper and had M4 feed ramps added to both for $30.
Bushmaster milspec chrome lined full auto bolt / carrier.
KAC carbine FF RAS
PRI charging handle
ARMS 40 rear
now I have a PRI front sight but you obviously dont need or want that and I dont think its needed (I just wanted it)

For the flash hider I put on the Gemtech Bilock which extends the barrel to the legal 16" and still allows me to mount the M4-96D suppressor even thogh I have a permanantly fixed flash hider in the future.

I assembled all this for free myself.  Its very easy to do with the correct tools.  Go to the hometown forum and find someone who will help you.  You will be amazed how little skill it takes to build an AR capable of MOA accuracy.

I would certainly get a 1/7 twist barrel for use with 75 and 77 grain ammo.  This will be just as good at extending range as a 16" 1/9 barrel using M193.  The 14.5" 1/7 twist barrel using 77 grian ammo would even have better terminal effectiveness and accuracy at ALL ranges compared to a 16" 1/9 barreled AR using M193.

As for the heavy M4 barrel.... you have a full auto lower you attaching this thing to?  No?  You not planning on using it as an improvised SAW?  Then why waste money and weight on a heavy M4 barrel instead of a factory M4 barrel when the factory M4 barrel is capable of MOA accuracy with match ammo?  Just my opinion.

First, thanks for the reply DevL



Ok, that makes sense to me.



Hopefully, never [:)] In all seriousness, I would want to use this out to 300 yds but for the most part, the ranges you mentioned (100-150m) are what it be mainly used for.



With an M-4 bbl, you're right. I can't have a fixed front sight with it but, with a hvy. bbl. I can. That being said, I'm going to just go with a carbine FF RAS.

I'm up in the air about the 14.5" vs. 16". I'll probably end up getting a 14.5" (plus Phantom) upper and a 20" upper.



That's what I'm probably going to end up doing - calling MSTN. I really don't want to mess around. I don't mind paying a bit more to have someone else do it. This isn't going on a project gun. This will be my main AR so I would rather pay to have someone do it right who has experience at it.



Well I don't plan on having a suppressor any time in the future so I'm too worried about the flash hider being permanently attached.



From everything I've heard and read, I agree with you. Building your own upper doesn't seem that difficult but I'd still rather pay someone else to do it. I don't have a lot of free time and want it done right.



That's the one thing I'm kind of stuck on - the 1/7 twist. I hear mixed opinions on  M193 in a 1/7 but for practice, it seems like it will be fine. I would definitely like to be able to start using the heavier 77gr stuff so I'm pretty much set on the 1/7.


And I appreciate it...your opinion that is. That's what I was hoping to get. Thank you for taking the time to respond to my post.