bushmaster upper help!

[lanceriley]

somebody is offering me a 14.5in bushmaster upper with flat top reciever.

my problem is... I've heard somewhere that bushmaster doesn't use an F marked FSB. what backup sight should I use?

I have not confirmed this since Im going to look at the upper on sunday.

barrel is chrome lined 1/9 is this good enough? I usually just shoot up to 200yards using irons. but mostly 100 yards using 55grain ball ammo.

[glockshooter]

I have used an arms #40 on mine without any issues, but I am sure that a Troy would work fine as well.

You ask if it is good enough, but my question is good enough for what?

Now a rant for all the replies that say BM is just simply garbage.

You are going to have numerous people tell you to get something else, but most (but not all) are simply saying that because someone else told them that brand X is the best. I have been through more rounds, schools, and classes than most (but not all) here. I will tell you that IF your BM has a properly staked gas key, and other simple upgrades it will work perfectly fine. Now when someone replies and says you should not have to fix a new gun, I will agree, but then again how many of us ever actually leave any of our guns stock.

Now for the people that are going to tell me I don't know what I am talking about, please tell me what personal experience you have personally had that differs from mine. Now as usual I would like to hear from the people that actually use their weapons. Now by use I don't mean the guys that go to the range once or twice a year, and barely shoot their weapon enough to get it dirty.

Lastly I will admit that BM is by far not the best thing out there according to the chart, TDP, or what ever you use to chose to determine what weapon is best by specs, but if you think that a weapon will work just because it has a certain part or parts inside you then that says all I need to know about how you pick and choose what is the BEST. I am a huge Sabre and LMT fan, and I would be happy to put my Sabre, or really my BM up against pretty much any brand out there.

There are a few well respected people on this forum that know me, and where I come from that I am sure can vouch that I am not just blowing smoke.

[Robb Jensen]

somebody is offering me a 14.5in bushmaster upper with flat top reciever.

my problem is... I've heard somewhere that bushmaster doesn't use an F marked FSB. what backup sight should I use?

I have not confirmed this since Im going to look at the upper on sunday.

barrel is chrome lined 1/9 is this good enough? I usually just shoot up to 200yards using irons. but mostly 100 yards using 55grain ball ammo.

Bushmaster doesn't use F height FSBs. Sometimes you can get them to zero just fine depending on your rear sight. If getting it zero'd requires the front sight post to stick high up and be very loose in the FSB just buy the optional taller front sight post from Bushmaster, is $5 or $6. For 55gr use the 1x9 twist will be fine. For rear sights I recommend Midwest Industries and Troy for flip ups. For fixed BUIS rear sights I like LMT, LaRue and/or just a chopped carry handle.

To get the most trouble free use out of your Bushy I recommend the following:

Have the carrier key staked properly (I remove them, lap the bottom and apply red loc-tite and stake using a MOACKS tool).
Ream the chamber to 5.56mm NATO dimensions in the neck and throat.
Run a H buffer (3.8oz) and standard rate chrome silicon buffer spring.
Buy a spare bolt I suggest a BCM bolt. (I would run the BCM and keep the factory bolt as a spare).
Use high quality mags like BCM or Brownells USGI mags, Lancer G5 mags or Magpul PMAGs.
Use quality ammo with sufficient power (PMC Bronze and Wolf is on the weak side, if using either run a CAR buffer (3.0oz).
Run the gun very wet with oil when actually shooting it.
If using a lower with a carbine/M4 collapsible stock be sure the receiver end plate is staked into the castle nut.

[lanceriley]

glockshooter.

What I meant was that if it's respectable enough to be shooting up to 200yards. barrelwise I mean. I don't have any experience with a bushy but if you say it's capable of delivering a round with a decent spread up to 200 yards then Im all for it.

gotm4,

that's what I was afraid of that I have to raise the front sight up that it wobbles. I can't get the taller front sight. Im in the Philippines. I might have to solder it.

I forgot to tell you that I have a complete lower already. I use it on my sbr 11.5in . retractible butt running a car buffer. bolt is a colt fa bolt from m16a1. In fact my lower is an m16a1 lower.

Bushmaster barrels aren't that popular in this forum. most people get the cmmg, lmt and popular barrels.

if 1/9 shoots well with 55gr that'd be good enough for me. 55gr is the only ammo readily available.

what about having 1/7 twist barrel? will it shoot 55gr too?