I have a Bushmaster fixed handle AR with 11.5inch barrel with 5 inch flash hider.
I want to put atleast a 16inch barrel on this gun.I dont know a whole lot about twist rate and crome lining and whatnot
The barrel i have now is chrome lined.This gun will not be used for competition or shooting quarters at a 100 yards.It will probably get around 1000-2500 rounds through it a year.
I would like just a standard M4 barrel,but like i said im unsure of the twist rate,and if i have to have chrome lining.Im only shooting basic factory loaded federal 55 grain bullits
Every other gun i have had has never had a chrome lined bore and they are fine,is their pro's and con's for this?I know the barrel now is very easy to clean
Is their a paticular brand of barrel you guys could recommend?
Im looking for a fairly priced barrel,does not have to be the best thing on the market,just has to get the job done
It is possible i might be changing the upper to a flattop,but im not sure about that just yet
Thanks for any info

get a 1/7 twist and chrome lined. BCM, Daniel Defense, Noveske, Sabre, White Oak are all top tier companies.

Chrome lining is a form of protection for the barrel in the event that cleaning it after use (combat, specifically) may not not be an option.  Or at least that's what it was originally designed to do.  That's one of the reasons why you won't see it on other, non-combat rifles.  I'm very diligent about cleaning my guns, but I still wouldn't get a carbine without a chrome-lined barrel.  It just makes sense, like car insurance.  You don't need it every day, but it's nice to know it's there.

I don't think you can go wrong with any chrome lined M4 profile barrel.  I would personally recommend Colt, CMMG, Sabre, and BCM because I am a fan of 1/7 twist rates.  This is useful if you're firing heavier bullets like 69 gr and heavier or 62 gr steel core ammo like SS109.

If you get an assembled upper, I'd recommend an LMT, in addition to the above mentioned.

For a 16" barrel just get yourself a quality midlength gas barrel from your choice of manufacturer, with a 5.56-compatible chamber.  Chrome lined, nitride, or stainless are all suitable, although stainless only in heavier profiles.  IMO 1:8 twist is preferable. 1:7 is acceptable but may be a poor choice depending on your ammo usage, if you exclusively shoot lighter and midweight bullets. 1:9 may be acceptable depending on your ammo choices, 1:9 is not recommended for 75 or 77gr bullets or the heavier solid copper bullets.

What does the twist mean as far as bullit weight?

In general, 1x9 is good for up to 69 gr. bullets. Altho all of the ones Ive encountered shoot 75's as well.  1x7 is considered good for up too 77 gr. +  weights.
If all you are going to shoot is 55's then a 1x9 will be good.  If you plan on shooting 75 and 77 gr. bullets then the 1x8 or 1x7 rates will be optimal.

Longer (heavier usually) bullets need a faster rate of spin in order to be stable in flight.

Shorter bullets don't need as much spin.

75 and 77 grain match hollowpoint (OTM) loads are the only off-the-shelf loads that aren't fully stabilized in a 1:9 twist, but they are popular with some because of their long range performance and terminal ballistics.  So, if you know you will be shooting those you need a twist rate faster than 1:9 for best results - some have had success with that combination but it's iffy.  It's a PITA because typical commercial barrels come in 1:9 and it's just barely not fast enough to cover the 75/77gr loads reliably.  1:8s are not very common especially in more practical barrel designs, 1:8.5s are almost nonexistant nowadays due to the competition use of the 80gr Sierra bullet which needs 1:8.  1:7 is the military specification twist which is far too fast for almost all shooters, but many like it because it will shoot all the heavier weight bullets.  Some like it because of the perceived superiority of "milspec".

It's subject to some debate, but (IMO) overly fast twists have a statistically higher chance of poor accuracy and other occasional issues with lightweight bullets.  The traditional maxim is that you get best performance out of a twist rate that is just fast enough to stabilize the heaviest/longest projectiles that you are using.

For the large majority of shooters it's all probably irrelevant, as most never shoot the heavy match OTMs, never shoot at a range long enough to see trajectory issues with light bullets in very fast twists, and don't have rifle configurations and/or aren't exacting enough shooters to discover any accuracy problems at either end of the spectrum.

So i reckon since i will be only shooting 55 grain bullits the 1/9 is fine?
Or would the 1/8 be a better choice?
Sorry for all the questions,i only want to buy one barrel,want to get it right the first time

1/9 will handle most common loads.  The heavier loads are not very common unless you handload or buy match type ammo.

Yes, if that's what you're shooting that is the better choice out of 1:9, 1:8, and 1:7.

Thanks for the help,i really appreciate it
Now,i must look for a barrel

Thanks for the help,i really appreciate it
Now,i must look for a barrel

PKfirearms carries Bushmaster 14.5/phantom flash hider barrel assemblies.I prefer higher end barrels I have Sabre defence,Daniel Defence,Colt and lower end barrels like BushmasterI like CMMG barrles as well...all are great and none have failed.Bushmaster is good quality for the money but even if it was a 4140 chromelined barrel those are also good for the semi-auto application.In the end the choice is yours and my philosophy would be no matter what end of the scale as long as its chromelined its GTG for me.

1/8 or 1/7 is the way to go.  Someone had a range report with 40 grainers and 1/7 twist and tight groups.  1/9 will never be better in an ar.  But dont make that a deal breaker, 1/9 will be fine up to 70, 75 grains.

if your only shooting 55 grain, any twist will work, 1/7 to 1/12.  however, if you may shoot heavier bullets, you'll want to pick accordingly.

Any twist will work???What will work the best?
Im looking at a daniel defence Barrel,sorry again for the repetetive question.
If i get a Daniel Defense Barrel that is a M-4,chrome lined bore,will it automaticallly have M4 feedramps,or would they specifiy that in specs.

Given your requirements and the ammo you will use, I would highly recommend a Bushmaster 14.5" 1/9 barrel with permanent Phantom flash hider.  PK Firearms had this getup for $250 last time I checked or somewhere in that neighborhood.  One of my favorite barrels I have ever owned is my Bushmaster 14.5", 1/9 M4 barrel.  

It will give you all the accuracy and durability you need, and if you will never shoot the heavy stuff there is no need to go 1/7.  And not every barrel has to be premium, 1/7, MP tested, made to the TDP, etc., etc., (and I'm not just saying that because I don't have them) - Bushmaster makes a solid barrel and is a good value for the money.

My $0.02.

ETA:  I will also say if you want to go 16" with removable FH, the previous recommendation for a midlength is the way to go.  Me personally, I've given myself over to the 14.5" with permanent FH as still the best setup for general purpose use (or at least, much preferred to 16" with carbine gas system).

ETA2:  Go for it, before I pick another one up and potentially buy their last one.

I juat orderd another complete upper to satisfy my taste,the spikes tactical complete upper they have on sale
seemed to be a good deal

I have Bushmaster,Daniel Defense,CMMG,Sabre Defence barrels..I paid a bit more for the premium ones and that was my choice for the steps taken in the production of those barrels but the lower end ones are fine too..hell a chromelined 4140 barrel or unlined should be fine as long as it was made right.The extra benefit higher end barrels give ill probably never notice as I dont shoot full-auto and dont use my carbine as a bullet hose as im not in combat.I will admit I like having the mental security of the part that the extra steps in production and testing provide but not enough to be able to afford to do all my rifles.My go to and back up have the more expensive barrels.

if your only shooting 55, any twist will work.  1/12(i wouldnt get this as it really limits your choice, and ive never seen one anyway), 1/9,1/8,1/7 all good to go with 55 grainers.  the 1/7-8 will let you shoot the heaviest bullets for better long range shooting if you choose.

personally id get 1/7 as the best m4style barrels are ussually that twist and you can probably get a good deal.  BCM, and Sabre make very good barrels, for high volume shooting id make sure its chrome lined and 4150steel.

opps, meant to edit the first post, not repost

anyway, what will work best depends on the barrel, one 1/9 barrel might shoot better than a 1/7, while a 1/7 might shoot better than a random 1/9.  people get very good accuracy from both twists with 55 grain bullets.  A better brand will do more to effect accuracy.  The main thing is consistent chroming and a coencentric bore.