User Panel
User Panel
User Panel
|
Posted: 9/18/2003 11:06:34 PM EDT
[#1]
Quoted: I've got an ARMS 40 and I have heard that you might need to get a taller front sight post from Bushmaster to zero it if you don't have a Colt Barrel. I've got a Bushmaster barrel (front sight tower foundry code of "9 R and a crown). Any thoughts? Thanks! mrf2 i thought that [i]colt[/i] was the one that used a taller front sight post, because their original removable carry handle was taller than normal A2 carry handles.. and others (armalite, bushwhacker, RRA, so forth) use a standard front post, which does indeed work w/the #40... or GG&G's or KAC's for that matter others can elaborate/correct me... Hope this helps!! |
|
|
|
Posted: 9/18/2003 11:33:56 PM EDT
[#2]
Install your #40, and 95% of the time, you'll have no problem.
-Troy |
|
|
|
Posted: 9/19/2003 8:16:14 AM EDT
[#3]
Alot more may depend on whose flat top upper you have. All A3 uppers are not the same.
As CB has stated many times, your ARMS #40 was designed to be used with a GI spec upper and barrel. You have something different, it's a gamble. |
|
|
|
Posted: 9/19/2003 9:05:08 AM EDT
[#4]
Thanks for the info, very interesting. I've got an RRA upper so I'll be interested to find out this weekend.
Thanks! mrf2 |
|
|
|
Posted: 9/19/2003 10:20:49 AM EDT
[#5]
Mrf - I too have an RRA with a FT and an A.R.M.S. #40 - no problem.
Good luck |
|
|
|
Posted: 9/19/2003 11:33:03 AM EDT
[#6]
JohnM,
It isn't the upper receiver spec, which we were able to determine (3-4 years ago, on AR15-L) were generally all the same except for very very early flattops (pre-Picatinny standard). The difference is the front sight base. Colt uses higher front sight bases on some barrels (these are stamped "F" on the left side, presumably for "flattop") than they use on fixed carryhandle guns. Everyone else uses the same sightbases for everything, so given that they're already shorter than Colt "F"-marked FSB, if they are towards the short side of the tolerance, they may require a taller front sight. -Troy |
|
|
|
Posted: 9/19/2003 12:43:02 PM EDT
[#7]
I have an RRA upper and A3 receiver with a #40 newly mounted. I sighted in this last weekend and noted that my front sight was a lot higher than I was comfortable with. The top of the post is at or slightly above the front sight "ears". Also the post is a little wobbly. I am going to see how many courses of thread hold that post in there. My Bushy is not like this. I suspect I might need the longer front post. I'll update you when I get this issue figured out.
Jeff D. |
|
|
|
Posted: 9/19/2003 12:46:08 PM EDT
[#8]
Regardless of where a manufacturing error occurs, front sight base or rear rail, its an elevation variation. This variation is where you get in trouble.
Granted there seem to be more problems steming from front sight housing variations but the rail on the receiver is a problem shown to occur as well. |
|
|
|
Posted: 9/19/2003 4:12:25 PM EDT
[#9]
Short/std. ht. front sight bases are for full length barrels, the higher base is for 14.5/16" lentgth carbine barrels. The after market makers did not do thier trigonometry, that's the touble with after market reverse engineered not to mil spec products. Example, If you were to put an 8 inch barrel on, you would need an even higher front sight base, or at least a higher front post. Mil spec rear sights are required to be a certain ht. off the center line of the bore and the flat top receiver dovetails off of that.
Good shootin, Jack Good shootin< Jack |
|
|
Win a FREE Membership!
Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!
You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.
AR15.COM is the world's largest firearm community and is a gathering place for firearm enthusiasts of all types.
From hunters and military members, to competition shooters and general firearm enthusiasts, we welcome anyone who values and respects the way of the firearm.
Subscribe to our monthly Newsletter to receive firearm news, product discounts from your favorite Industry Partners, and more.
Copyright © 1996-2024 AR15.COM LLC. All Rights Reserved.
Any use of this content without express written consent is prohibited.
AR15.Com reserves the right to overwrite or replace any affiliate, commercial, or monetizable links, posted by users, with our own.
