I reccently aquired a pre-ban Bushy with tele stock, A2 upper and 11.5 barrel w/ 5.5 suppressor. I have thougt of ordering an M4 14.5 upper but dont really want to spend the $$$$ right now. What are your thoughts on the 11.5 vs 14.5 on the points of

*accuracy
*veloicty
*reliability
*noise

and any other points that I might consider.

You also have the options of

1. buying a just a new barrel

2. trading your upper for somebody elses

3. selling your upper and buying another of your choice.

An 11.5" barrel with a 5.5" suppressor is nothing but a waste of barrel length that could be taken up by velocity increasing rifling.

I have a couple of those 11.5" uppers. The first one, I intended to take apart and build up to a different configuration and the second one I bought because I wanted the pre-ban lower. Of course I ended up shooting them. Just as was posted above, I found that there was a significant difference in velocity. I don't have the figures in front of me, but the jump between 11.5" and 14.5" is one of the bigger jumps when comparing various barrel lengths. Both uppers shot OK. I didn't do any real serious accuracy testing, but when zeroing at 50 yards, they shot groups that were pretty typical of what I could shoot with iron sights at that range. I personally didn't notice the difference in noise but then, my 14.5 is a Bushmaster M4 with the mini-y-comp muzzle brake which is very loud itself.
If you don't have the money for a new upper, just shoot the one you have and enjoy it. Personally, I am a civilian and don't anticipate being in a long range firefight in the near future, so I am not all that concerned with the lack of fragmentation. Of course this lack of fragmentation is primarily a factor when using mil-surp ammo. You can increase it's effective range by using civilian ammo such as softpoints, hollow points, or ballistic tips. If you are shooting paper, or plinking, this is not even an issue.

Actually M193 from an 11.5" barrel will fragment out to about 50 meters.  On the other hand though I would have to agree with what everyone else is saying.  If you have to meet the 16" legal limit then by all means make sure all of it is with actual barrel.  I myself am in the process of registering one of my lowers as an SBR so I can mount a true 11.5" barrel with an A2 FS.  In this configuration there is a definate advantage for CQB.  5.56 will be much more effective than any pistol round from a subgun and will also be able to penetrate soft body armor.

I should have mentioned the primary reason I want a 14.5 barrel is for the correct mounting of a bayonet......yeah, I know what you are going to say, who has a need for a bayonet? and I will hopely never have a need for one but I just feel that a bayonet is part of the weapon 'system' and I want to retain the ability of that system.
BTW I am not too crazy about the phantom/vortex FS (their OK) but I like the look of the streched A2 type FS from Kurt's Kustoms, anyone have any experience with them?

Yeah; but if it's an XM177E2 clone it's still the sexiest thing around [:D]

Have had one, built on an SP1 lower, for over 25 years. It's still my favorite AR, and I've got four (soon to be five) others.

While I acknowledge the personal taste/asthetic aspect of different people, I must add the following comment.

The two you dont like, happen to be the very best [i]flash hiders[/i] money can buy. Phantom at 90+% & Vortex at 100%.

Good luck!

jstep,

I have an 11.5/5.5 Bushmaster CAR and two 14.5" M4s and like shooting my CAR more.  It's just as accurate at 25-50 yards (which is where I do most of my shooting) as my 14.5" M4s.  Maybe a better shooter could tell the difference but I seem to be just as accurate with both.

I haven't noticed a difference in the noise level between the two.

As far a veloicty goes I'll agree with 444: I don't plan on being in a "long range firefight" so fragmentation is not an issue for me.  If I ever had to use it then it would most likely be inside my house and 15 yards would be plenty.

I say you keep it as is and shoot the hell out of it!  Besides, it is sexy as hell [;)]