View Full Version : Why did I have to adjust my sights so much?
I went to the range yesterday and was zeroing my Bushmaster (XM15-E2S) in at 100yds. I was shooting about 2 ft high at first! The rear sight (removeable carry handle) was adjusted all the way down and I was using the small aperature. I had to raise the front post quite a few turns (maybe 6 or 7 steps). I don't have an F marked FSB and the upper is a flat top with the carry handle attached. Is there any reason I would need an F marked FSB or the taller front sight post? I was using mostly 62gr silver bear, btw. I can't understand why I would be shooting so high... Other than the adjustments the mill ran great!
taller fron sight post .040... Bushmaster doesen't use the F marked front sight base...
PK Firearms has them for $7.50... Hope this helps you out...
But isn't the factory detachable carry handle supposed to work with the standard height FSB? This is how it came so I would just expect it to function properly...
m4forme gave you the correct answer. Not an F marked front sight. It's lower. So to compensate, you have to raise the front sight you have. Just as m4 explained. The carry handle is not made specifically for the lower front sight. Don't worry. There is enough adjustment in your front sight to get it shooting correctly.
https://www.m4carbine.net/showthread.php?t=40916
lmt rear buis... i measured my other AR's sight posts on my flatops (BCM & Stag) and they are shorter than the Bushmaster...
Quib gave you an excellent reference. My son owns the same BM as you. Given to him by a coal company last Christmas as a gift. His had enough adjustment(without being loose) to zero at 50/200. Your's may or may not. You can do as Quib has suggested.
Way back in the day when I bought my first AR it was the same flat top model from Bushmaster. My rifle did the same thing and I couldn't get it to zero even with the front sight all the way up even when it was loose and wobbling. I contacted Bushmaster and they said to ship the upper back. They checked and found the upper was quote: "out of spec".
Regardless they sent me back a new upper, or new barrel of new FSP I couldn't tell what they replaced and it was zeroed with the front sight at a normal height. Turn around time was about one week.
I have since sold the Bushie, and while the way their rifles leaves the factory isn't up to the best standards, I have nothing bad to say about Bushmaster's after sales service.
Cameron
Edited due to lack of caffeine intake. :D
LOL. That was meant in response to the OP.
LOL. That was meant in response to the OP.
LOL......then I stand corrected. :D
I’m only on cup of coffee #2. ;)
I went to the range yesterday and was zeroing my Bushmaster (XM15-E2S) in at 100yds. I was shooting about 2 ft high at first! The rear sight (removeable carry handle) was adjusted all the way down and I was using the small aperature. I had to raise the front post quite a few turns (maybe 6 or 7 steps). I don't have an F marked FSB and the upper is a flat top with the carry handle attached. Is there any reason I would need an F marked FSB or the taller front sight post? I was using mostly 62gr silver bear, btw. I can't understand why I would be shooting so high... Other than the adjustments the mill ran great!
Six or seven stops isn't a problem unless it's putting the base of your FSP above the flat of the front sight base. If it does, call BM with your ser# and they will send you a taller FSP.
Thanks for the responses guys. Taller FSP is going to be my resolution, as you suggested. I am just surprised that a rifle comes from the factory with the wrong equipment. The FSP is close, but not above the FSB protective ears, btw. I do intend to run optics/BUIS eventually so I might as well solve this now.
Normally the rifle is zeroed for 25/300 meters and the front sight is tall enough for that. When you zero for 50 or 100m you can run out of adjustment.
If you get the taller sight look at the Santose IBZ so you can zero at 25 and 50. The RIBZ will give you those and a 100 yard zero too. You've got the removable carry handle so you're set, just need the tall sight and a 1/16" Allen wrench.
Just got off the phone with Bushmaster. Taller FSP is on the way, free of charge. Good people, great customer service.
meisterhau
11-13-09, 19:04
Just got off the phone with Bushmaster. Taller FSP is on the way, free of charge. Good people, great customer service.
I had exactly the same issue here... had hell trying to sight in this gun - getting a bit pissed, actually. Finally got a hold of a Lead Sled DFT, to abso-posi-lutely sight in my guns. Front post had to be screwed out so far that the body of the detent was actually slightly above the FSB body. The post is wobbly, as the base is completely out of the FSB body. Totally different than the Colt, which sighted in at 50 is actually down in the body a ways... very secure.
"F" on the Colt, not on the Bushmaster. Figured a call to them wouldn't hurt. In less than the time it took for my wife to drive 1 mile each way to pick up a pizza (which was done) and grab the mail out of the box, I looked up their number, made the call, described the issue, gave my shipping info, and the rep said he'd have a taller post in the mail to me Monday, free of charge.
In a world of "ain't my problem" and "nuthin' for free", a world of shit customer service and professional-level buck-passing, they definitely get a thumbs-up. Hopefully this will fix the problem... if not, I suppose it's another discussion with them, or a swap-out for an "F" FSB.
Just got off the phone with Bushmaster. Taller FSP is on the way, free of charge. Good people, great customer service.
However, a real "top tier" company wouldn't have the problem to begin with. It's obviously a pretty common problem with Bushmaster.
However, a real "top tier" company wouldn't have the problem to begin with. It's obviously a pretty common problem with Bushmaster.
I appreciate your input toward resolving my issue. Thanks...:rolleyes:
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.