View Full Version : A2 carry handle sight - windage adjustment. How much is too much?
Without getting too long winded here, bought a complete M16A4 style rifle last spring from a mfg everyone would recognize. Couldn’t get a BZO. Sent the upper back and the mfg said they adjusted the front sight which I assume was canted.
I can zero the rifle now (using a Marine style 25 yard BZ), but doing so requires me to crank the windage adjustment on the carry handle rear sight almost completely to the left (there are a couple of clicks left). The POI is on target.
Is that acceptable and in spec, in terms of quality that someone should expect for a AR-15? Am I being too picky? If it zeros, just be happy and shoot it?
Hell no. You can't adjust the front sight. The index pin on the barrel extension and the FSB are permanently where they will always be.
There's a spec for the military's acceptance I read somewhere along the way. It's like 10-12 clicks off of mechanical zero. I had a bushmaster upper receiver that was like 10 clicks off of mechanical zero, and I replaced it. I knew it was the upper because I'd had that barrel work fine on another upper. Eff that!! I trued the receiver face and it got like 1 more click worse. No way. I can't live with that slop at all.
I'd get a new upper as it sounds like it is still clocked to me.
There are potential problems beyond the obvious eye sore of a wonky upper half. I Don't know why the bushcrapper upper was crooked, but if the bolt isn't locking into the barrel perpendicular, the lugs aren't locking evenly and correctly.
There are potential problems beyond the obvious eye sore of a wonky upper half. I Don't know why the bushcrapper upper was crooked, but if the bolt isn't locking into the barrel perpendicular, the lugs aren't locking evenly and correctly.
Yep and if there are no M4 RE cuts, as is likely the case with an "M16", it would be hard to recognize a clocked RE / Barrel / both.
ETA: As a comparison, both of my recently acquired Colt LE6920's required only 3-5 clicks of adjustment to be dead on at the range when zeroed.
OK you folks convinced me. Called, got an RMA, and put the upper in a box and dropped off at UPS to go back to the factory.
Requested a replacement but I assume I have no real say. If they claim it’s fixed and send it back to me, I can’t do much except complain and never place another order from them again.
I got a new HBAR in 90 and when I zeroed it at 100 yards I had two clicks left. I called Colt, they said to send it back and I did and they put on a new barrel. It is not uncommon to get a crooked bore internally.
If they return it and there's no change, you could try another upper receiver. That was my issue. I just happened to know it because they barrel was in another upper without the problem.
However if the FSB is reamed out of top dead center, there's no fix that I know of. The index pin/barrel extension is nearly permanently in place, and the FSB ream job can't be adjusted.
If they return it and there's no change, you could try another upper receiver. That was my issue. I just happened to know it because they barrel was in another upper without the problem.
However if the FSB is reamed out of top dead center, there's no fix that I know of. The index pin/barrel extension is nearly permanently in place, and the FSB ream job can't be adjusted.
Pretty sure that can be tweaked some. Slightly oversized taper pins and...
Uppers like the one you mentioned can be trued up as well with shims on the one side.
Pretty sure that can be tweaked some. Slightly oversized taper pins and...
Uppers like the one you mentioned can be trued up as well with shims on the one side.
No in spec gun I've ever worked on had any play in the index pin notch... definitely not enough to make up for a windage issue. Maybe a couple thousandths, but they generally lock up with little play at all.
And there's zero room for taper pin adjustment that I can see. I mean... that FSB goes on ONE way, exactly where the pins and FSB were reamed. A small pin would just seat deeper, and a larger pin more shallow, but the holes line up one way.
No in spec gun I've ever worked on had any play in the index pin notch... definitely not enough to make up for a windage issue. Maybe a couple thousandths, but they generally lock up with little play at all.
And there's zero room for taper pin adjustment that I can see. I mean... that FSB goes on ONE way, exactly where the pins and FSB were reamed. A small pin would just seat deeper, and a larger pin more shallow, but the holes line up one way.
John Thomas for one has fixed stuff like that before. Pretty sure he is not alone but he gets mentioned (and praised) a lot for that sort of work on the internet. It can be done...
Fitting / Shimming an index pin notch is something that is sometimes done as well.
militarymoron
01-26-22, 22:39
Fitting / Shimming an index pin notch is something that is sometimes done as well.
This - you can open up the index pin notch on the receiver a bit so the barrel can rotate, or file one side of the barrel index pin. The gap on the other side can be filled with a thin stainless steel shim which will be captured once you install the barrel nut. But, before you do that, you can determine whether the barrel is rotated in the receiver or the front sight tower is leaning by looking at the feed ramps. If the feed ramps line up perfectly, then it's the front sight tower that's leaning. You usually do have a little bit of rotation to play with for feed ramp alignment if you do want to make the adjustment.
This - you can open up the index pin notch on the receiver a bit so the barrel can rotate, or file one side of the barrel index pin. The gap on the other side can be filled with a thin stainless steel shim which will be captured once you install the barrel nut. But, before you do that, you can determine whether the barrel is rotated in the receiver or the front sight tower is leaning by looking at the feed ramps. If the feed ramps line up perfectly, then it's the front sight tower that's leaning. You usually do have a little bit of rotation to play with for feed ramp alignment if you do want to make the adjustment.
This is all well and good, but the fact remains that it should not NEED to be done. The item the OP purchased is out of spec. It should be replaced.
If I buy a new truck, I expect it to meet alignment tolerances without having to modify the frame.
Years ago, I was told by a big manufacturer that 13 clicks from center to zero windage was acceptable for a rear sight. I've seen rifles and carbines made by the same company require the rear sight to be adjusted all the way to the left to zero.
I've reindexed a considerable number of barrels to get the rear sight to no wind zero with the rear sight centered. It shouldn't have to be done on an expensive rifle or carbine made by a company that is popular on M4C, but it is more commonplace than I think acceptable.
This - you can open up the index pin notch on the receiver a bit so the barrel can rotate, or file one side of the barrel index pin.
I absolutely DO NOT want that gun. That is an unacceptable work around to me.... Especially going back to my example where it is not the FSB pinned off of TDC, but the receiver is not straight.
If someone here bought a gun, took it apart and saw that crap??? There'd be hell to pay for the manufacturer sneaking that crap into a customer's hands.
militarymoron
01-27-22, 13:07
This is all well and good, but the fact remains that it should not NEED to be done. The item the OP purchased is out of spec. It should be replaced.
If I buy a new truck, I expect it to meet alignment tolerances without having to modify the frame.
Agreed - if the whole assembly is from one manufacturer then send it back. And, good quality components should need no such alteration. But, sometimes when piecing together a frankengun; the kitchen gunsmith methods can help.
Does the front sight base appear to be canted to the left when the rear sight is held level? If you look at the muzzle, does the bore appear to be off center?
Does the front sight base appear to be canted to the left when the rear sight is held level?
This is hard to tell. At least for me. And FSB forging "ears" are not always symmetrical where you could put a level on top.
If you look at the muzzle, does the bore appear to be off center?
This would be a unusual since the blanks are shaped after gun drill. (unless this is a Hammer Forge barrel of course) We did have a shillen barrel on a bolt gun that supposedly had this problem though.
Could be just a bad barrel that throws bullets left/right.
I can't imagine getting an untrue FSB ream if they used a real reaming station. And if it's BCM or FN, they'd both surely be using this tooling.
It seems like this problem used to be more commonly reported in the past. I doubt they'll tell him what the problem is, but now I'm curious.
I absolutely DO NOT want that gun. That is an unacceptable work around to me.... Especially going back to my example where it is not the FSB pinned off of TDC, but the receiver is not straight.
If someone here bought a gun, took it apart and saw that crap??? There'd be hell to pay for the manufacturer sneaking that crap into a customer's hands.
You mentioned above what the military deemed as 'acceptable' I believe. And you also mentioned selling one that you bought that was 10 clicks off? (that still falling inside of what you said the military would accept)
Plenty of other guys around here that would be able to diagnose the problem and possibly correct it on their own without selling or returning anything...
Point being - Depending on the problem and the severity - Sometimes that stuff can be adjusted / tweaked to the point where everything is perfect.
All of the parts we are discussing have 'tolerances' and there is no shame in having a shim here or there to make things closer to being perfect for a customer or an owner.
This is hard to tell. At least for me. And FSB forging "ears" are not always symmetrical where you could put a level on top.
This would be a unusual since the blanks are shaped after gun drill. (unless this is a Hammer Forge barrel of course) We did have a shillen barrel on a bolt gun that supposedly had this problem though.
Could be just a bad barrel that throws bullets left/right.
I can't imagine getting an untrue FSB ream if they used a real reaming station. And if it's BCM or FN, they'd both surely be using this tooling.
It seems like this problem used to be more commonly reported in the past. I doubt they'll tell him what the problem is, but now I'm curious.
I've corrected the sights on a considerable number of AR's by loosening the barrel nut, moving the barrel and tightening the barrel nut to correct torque.
You mentioned above what the military deemed as 'acceptable' I believe. And you also mentioned selling one that you bought that was 10 clicks off? (that still falling inside of what you said the military would accept)
I read somewhere where there's a acceptable windage from mechanical ZERO. But I would NOT have such loose tolerances for my guns. I ABSOLUTELY would not sell a POS receiver to anyone. I'd never pass garbage on unless the buyer knew it and still wanted it.
Plenty of other guys around here that would be able to diagnose the problem and possibly correct it on their own without selling or returning anything...
Point being - Depending on the problem and the severity - Sometimes that stuff can be adjusted / tweaked to the point where everything is perfect.
All of the parts we are discussing have 'tolerances' and there is no shame in having a shim here or there to make things closer to being perfect for a customer or an owner.
My point is simply that if any guy ON THIS SITE were to buy an AR and find some booger eater fix on the gun when the took it apart, there would be a witch hunt on that manufacturer. And rightly so! These silly mods are totally unacceptable in my opinion.
I've corrected the sights on a considerable number of AR's by loosening the barrel nut, moving the barrel and tightening the barrel nut to correct torque.
I tried that with my shit upper, and it didn't work. In fact, truing up the receiver actually put it another click or to off to retardville.
You just need a lead hammer and a railroad tie with a 1" hole in it...
Andy
I tried that with my shit upper, and it didn't work. In fact, truing up the receiver actually put it another click or to off to retardville.
Who made the upper?
Who made the upper?
Here's the POS in question. I found it. Like I said somewhere in the thread, It's supposed to be a Bushmaster bought stripped from who knows where.
It's WORSE than I remember 16 clicks off mechanical ZERO to get the turd on target.
https://i.imgur.com/9gsWS0t.jpg
Here's the POS in question. I found it. Like I said somewhere in the thread, It's supposed to be a Bushmaster bought stripped from who knows where.
It's WORSE than I remember 16 clicks off mechanical ZERO to get the turd on target.
https://i.imgur.com/9gsWS0t.jpg
Looks like you rescued it from a dust devil.
I tried that with my shit upper, and it didn't work. In fact, truing up the receiver actually put it another click or to off to retardville.
Kindof funny how you see no problem with having to true a receiver face but it becomes a 'turd' if you need to adjust the index pin notch a slight bit...
lol! :)
PS: If your receiver tool is the one from Pacific can I borrow it for a few days? Have 3 that would not hurt to be done. Have my own lapping compound already... Will gladly pay all the shipping back and forth.
Without getting too long winded here, bought a complete M16A4 style rifle last spring from a mfg everyone would recognize. Couldn’t get a BZO. Sent the upper back and the mfg said they adjusted the front sight which I assume was canted.
I can zero the rifle now (using a Marine style 25 yard BZ), but doing so requires me to crank the windage adjustment on the carry handle rear sight almost completely to the left (there are a couple of clicks left). The POI is on target.
Is that acceptable and in spec, in terms of quality that someone should expect for a AR-15? Am I being too picky? If it zeros, just be happy and shoot it?
So I got an RMA and sent the upper back. Requested a replacement, but obviously I can only ask.
Just received this from PSA which is who assembled and sold it. I wasn’t going to say who it was, but figured WTF? If they don’t want me saying, then don’t ship products that aren’t built correctly.
“ The following repairs were completed on your Palmetto State Armory product:
Put the FSB gauge on the upper and had to make minor adjustments to make center.”
Does that sound plausibly correct? Or are they just jacking me off?
Here's the POS in question. I found it. Like I said somewhere in the thread, It's supposed to be a Bushmaster bought stripped from who knows where.
It's WORSE than I remember 16 clicks off mechanical ZERO to get the turd on target.
https://i.imgur.com/9gsWS0t.jpg
16 clicks is entirely too much off center IMHO. Most uppers I've seen have the rear sight adjusted way left of center to zero.
Here is something I do to verify the front sight is plumb when the receiver is level. On a carbine or rifle with detachable carry handle, I remove the carry handle and put a 36" or longer straight edge on the flat on top of the receiver. If you have a fixed carry handle, place the straight edge on the flats on the bottom of the upper receiver. Then I shine a bright light through the straight edge and FSB, transpose the shadow on a plumb line I have drawn on the wall in my workshop, then level the shadow of the straight edge. It's easy to see if the straight edge is level when you look at the shadow on the wall. The shadow of the FSB will show you if it's canted. It's old school, but it works. I learned this technique using two straight edges to verify proper index when installing barrels on M1 Garands, 1903 Springfields, 1917 Eddystones, etc.
A 13/64" drill rod will tell you if the barrel is bent. The rod is .203" in diameter and the minor diameter of a .223 caliber bore is .219". That gives you 0.016" clearance. If the rod drags inside a 16" barrel, that tells you the barrel has more than 0.001" deflection per inch. Make sure the barrel is squeaky clean or you will get a false reading. If the rod will only go halfway down a clean barrel, you have a problem.
I've shot old Mausers with bent barrels that shot good groups, but the front sight was way off center. I can think of no reason that should be tolerated on a modern AR-15. On a modern firearm, produced on modern equipment, IMHO the rear sight should not be more than 6 clicks from center when zeroing on no wind day, using your dominant eye. If your dominant eye is the left eye, and you shoot right-handed, the rear sight will most likely be off center to zero.
Armalite used to sell a clamp on FSB that made it easy to zero windage. Fire a few shots, move the front sight base, fire a few more shots, repeat as necessary. When you're happy with your zero, torque down the screws.
the AR-15 Junkie
01-31-22, 19:43
Last summer I designed a cheap under 70$ front sight block "can"t gauge, then gave away FREE the design and part#s.
I checked about 18 Colts, all were perfect but 2. Those 2 had aftermarket rails. 16 Colts with pinned on FSBs were all perfect. The majority of the videos on my Youtube is checking FSB cant.
Here is a couple of vids of it being used and the How too Video, to build your own.
https://www.youtube.com/watch?v=FZeyoa15u3Y
https://www.youtube.com/watch?v=rQMz-WUrgtQ&t=176s
https://www.youtube.com/watch?v=HWpvAuT4NIE How Too Build video!
“ The following repairs were completed on your Palmetto State Armory product:
Put the FSB gauge on the upper and had to make minor adjustments to make center.”
Does that sound plausibly correct? Or are they just jacking me off?
Yes, They could have adjusted it some.
Last summer I designed a cheap under 70$ front sight block "can"t gauge, then gave away FREE the design and part#s.
I checked about 18 Colts, all were perfect but 2. Those 2 had aftermarket rails. 16 Colts with pinned on FSBs were all perfect. The majority of the videos on my Youtube is checking FSB cant.
Here is a couple of vids of it being used and the How too Video, to build your own.
https://www.youtube.com/watch?v=FZeyoa15u3Y
https://www.youtube.com/watch?v=rQMz-WUrgtQ&t=176s
https://www.youtube.com/watch?v=HWpvAuT4NIE How Too Build video!
I've done something similar to this, but changed the way I check alignment so I do not have to remove the rear sight.
With the front sight post removed and rear sight assembly removed from the carry handle, I put the rifle in a vise or other fixture on the floor and lay a 36" long piece of 5/8" round stock on top of the carry handle and front sight wings. Standing over the rifle, the round stock should be parallel with the barrel and receiver extension or stock.
I am always looking for new ideas.
Thanks.
So I got an RMA and sent the upper back. Requested a replacement, but obviously I can only ask.
Just received this from PSA which is who assembled and sold it. I wasn’t going to say who it was, but figured WTF? If they don’t want me saying, then don’t ship products that aren’t built correctly.
“ The following repairs were completed on your Palmetto State Armory product:
Put the FSB gauge on the upper and had to make minor adjustments to make center.”
Does that sound plausibly correct? Or are they just jacking me off?
First off, the amount of people here who say that PSA has great products and great quality control is going to be minimal. I'm waiting for them to jump in to defend their beloved company, but they won't. Nor will you find the company willing to come over here and defend any of their products or practices.
I would guess your upper receiver group was adjusted via dead blow hammer. You take the weapon, lay it down, knee on it to keep it flat, and smack the FSB hard a few times, then look and see if it seems any better. If not, repeat the "whack a mole" procedure until it does.
I will note, I have no evidence nor am I making any form of accusation. I am stating that my belief is the above, or a similar procedure was conducted. I base my comments on my long time training and experiences as an armorer as well as industry information.
On a brighter note, hopefully this "adjustment" fixed the problem for you. Let us know how she zeroes out now!
PSA?
Well, like mamma always said, "If you can't say anything nice, ..."
Color me not surprised. Pretty sure Stick accurately described their "truing procedure".
l
I would guess your upper receiver group was adjusted via dead blow hammer. You take the weapon, lay it down, knee on it to keep it flat, and smack the FSB hard a few times, then look and see if it seems any better. If not, repeat the "whack a mole" procedure until it does.
I will note, I have no evidence nor am I making any form of accusation. I am stating that my belief is the above, or a similar procedure was conducted. I base my comments on my long time training and experiences as an armorer as well as industry information.
On a brighter note, hopefully this "adjustment" fixed the problem for you. Let us know how she zeroes out now!
Thanks for your comments. I understand you’re merely taking an educated guess on what might have been done.
My question is how does that form of “repair” affect the barrel/rifle? Any negative effects or if it zeros then forget about it and have fun?
Thanks for your comments. I understand you’re merely taking an educated guess on what might have been done.
My question is how does that form of “repair” affect the barrel/rifle? Any negative effects or if it zeros then forget about it and have fun?
I've found FSB taper pins some of the most difficult AR15 pins to remove. The dead blow hammer will make them even more difficult to remove should that ever be required.
Depending on what they did and how they actually did it, I'd look in two additional areas for issues. 1. Clocking of the feed ramps 2. galling or deformation of the barrel alignment slot in the upper receiver.
Were I in your shoes, I'd be a hell of a lot happier if they had replaced the defective upper. Hopefully it isn't necessary, but perhaps they will on a 3rd return trip?
Regardless, I am curious how this turns out for you.
I'd say you've gotten all you are gonna get from PSA. If it zeros, great, shoot it. If it don't? Might be a good candidate for a shaved FSB and a long rail.
But yeah, there are some potential (if unlikely) down side risks to this form of "repair". Smacking shit with a hammer is almost never the right answer. I try to tell myself that nearly every time I resort to it. :p
PSA?
Well, like mamma always said, "If you can't say anything nice, ..."
Color me not surprised. Pretty sure Stick accurately described their "truing procedure".
Yeah, the thing for me that’s annoying is it went back once already. So they returned it to me once without actually fixing.
I've found FSB taper pins some of the most difficult AR15 pins to remove. The dead blow hammer will make them even more difficult to remove should that ever be required.
Depending on what they did and how they actually did it, I'd look in two additional areas for issues. 1. Clocking of the feed ramps 2. galling or deformation of the barrel alignment slot in the upper receiver.
Were I in your shoes, I'd be a hell of a lot happier if they had replaced the defective upper. Hopefully it isn't necessary, but perhaps they will on a 3rd return trip?
Regardless, I am curious how this turns out for you.
Well just got another email from customer service. Maybe they read this forum? 😁 That sounds better if they changed the barrel.
“The following repairs were completed on your Palmetto State Armory product:
Changed barrel and put on FSB gauge and test fired.”
First off, the amount of people here who say that PSA has great products and great quality control is going to be minimal. I'm waiting for them to jump in to defend their beloved company, but they won't. Nor will you find the company willing to come over here and defend any of their products or practices.
I would guess your upper receiver group was adjusted via dead blow hammer. You take the weapon, lay it down, knee on it to keep it flat, and smack the FSB hard a few times, then look and see if it seems any better. If not, repeat the "whack a mole" procedure until it does......
That is exactly what I was told by a person who worked for a large firearm company. Before I would send a rifle back to have it adjusted, I would do it myself or hire a competent AR armorer.
Well just got another email from customer service. Maybe they read this forum? [emoji16] That sounds better if they changed the barrel.
“The following repairs were completed on your Palmetto State Armory product:
Changed barrel and put on FSB gauge and test fired.”
Well that is certainly good news!
That should in all likelihood Square you away.
I had a similar experience on a cheap 11.5” build I did. Beater pistol, so no issue with “cost effective.” But this was my zero…
https://i.imgur.com/jz5TNWM.jpg
Sent it back, got the generic message of what was done. And when it came back, zeroed more centered. I’d say windage was close to 2-4 clicks from center. Couldn’t remember, being it looks good. Made sure it ran, and sort of done with it.
PSA… they are what they are. They put out guns for a lower cost, and while I’m not a huge PSA fan, there are plenty of shooters that have an AR (or multiple ARs) because of them. QC isn’t awesome, but if you have a problem… let them know and they will get it squared away.
I wanted a 20” A4 upper for a build I was planning, and was leaning towards their FN barreled upper. I ultimately didn’t go that route, since I traded my Tavor for a NM rifle that I pieced into two ARs (the A4 build… and a lower for my .22 upper). But if I did, I was going to pull a BUIS rear off another gun and confirm whether the FSB was aligned. This upper is running a 1-6x LPVO, and won’t be using irons… but if I ever repurposed the upper, I’d want it zeroed somewhat normally. It’s an AR… not an AK. Don’t want sights that far off center.
I've found FSB taper pins some of the most difficult AR15 pins to remove. The dead blow hammer will make them even more difficult to remove should that ever be required.
That method does not move the FSB or do squat to those pins nor is it intended to.
shrimpcaptain
02-02-22, 09:52
I have the same issue with a PSA nitride dissipator upper (el cheapo). I just got a return authorization for repair. I can tell the fsb is canted a bit to the left. Glad to know that your issue was resolved.
I have the same issue with a PSA nitride dissipator upper (el cheapo). I just got a return authorization for repair. I can tell the fsb is canted a bit to the left. Glad to know that your issue was resolved.
Hopefully it is, but won’t know for sure until I get the upper back. They told me it was fixed last time and it wasn’t.
Hopefully it is, but won’t know for sure until I get the upper back. They told me it was fixed last time and it wasn’t.
Same issue or different?
Same issue or different?
Same.
Same.
Damn. :(
If you get this upper back and it is not dead ass on the money right I would suggest returning it and demanding a full refund and then go on a picture posting spree both here and at AR15.com in their section of the industry forum.
You gave them two chances to get things right... If they fail on this second chance and send you back some crap that is still jinky you should let as many others as possible KNOW just how things were handled and what sort of products you were sold.
You definitely have more patience than I do allowing them a second chance to make things (the same exact problem) right.
You definitely have more patience than I do allowing them a second chance to make things (the same exact problem) right.
Well, not sure what choice I have other than wasting my time and sending it back again and again.
Hopefully, if they actually put a new barrel on it, they did it properly and without a canted FSB. But if it’s still messed up then I’ll just quit buying from PSA and get a new upper and replace it myself.
I’m optimistic this time. 🙂
Well, not sure what choice I have other than wasting my time and sending it back again and again.
Hopefully, if they actually put a new barrel on it, they did it properly and without a canted FSB. But if it’s still messed up then I’ll just quit buying from PSA and get a new upper and replace it myself.
I’m optimistic this time. 🙂
Without more investigation on your part how do you really know if it is the barrel or the upper?
You could have a FSB that was installed by a drunk monkey or is it the upper receiver that is out of spec in a bad way???
If they stuck a new barrel on a receiver that was causing the problems - what problems were solved?
Refund is the other choice you have if they continue to fail here...
Without more investigation on your part how do you really know if it is the barrel or the upper?
.
All I can do is zero it and see if it’s close to mechanical zero or way off like before.
This is a range toy, so it’s not something I’m depending on for my safety. Next time, I’d get a Colt or a Windham.
I had an all original Colt AR-15 A2 Sporter II Carbine with the same problem
The rear sight unit was at fault, I replaced it and all was in order
https://uploads.tapatalk-cdn.com/20220203/b54cc4913a5050f86d58f7f736d33bc3.jpg
I had an all original Colt AR-15 A2 Sporter II Carbine with the same problem
The rear sight unit was at fault, I replaced it and all was in order
Wouldn’t they check that by swapping the carry handle? I guess if there was an obvious cant or other issue with the barrel geometry then they might not even bother.
I had an all original Colt AR-15 A2 Sporter II Carbine with the same problem
The rear sight unit was at fault, I replaced it and all was in order
https://uploads.tapatalk-cdn.com/20220203/b54cc4913a5050f86d58f7f736d33bc3.jpg
Did you replace the rear sight assembly or the entire carry handle?
Wouldn’t they check that by swapping the carry handle? I guess if there was an obvious cant or other issue with the barrel geometry then they might not even bother.
Did you replace the rear sight assembly or the entire carry handle?
Just the rear sight assembly. It’s a fixed carry handle
https://uploads.tapatalk-cdn.com/20220203/6182c6af33c5c09ea2615d412053d093.jpg
I had an all original Colt AR-15 A2 Sporter II Carbine with the same problem
The rear sight unit was at fault, I replaced it and all was in order
Where that aperture sits in relation to the sight tunnel on your handle will not change when the rifle is zeroed just because you changed out the rear sight base for one with a tiny bit of difference in width (allowing for more threads / adjustment to the left).
That rear aperture really should be sitting closer to the middle of the handle tunnel. It's not because something aside of your rear sight assembly is tweaked. (your FSB or how the barrel is clocked in your upper)
That method does not move the FSP or do squat to those pins nor is it intended to.
Don't cherry pick bud. Read the post in its entirety.
It would appear that a clamp on FSB is being manufactured again.
https://www.shop.deztacticalarms.com/A2-Fixed-Front-Sight-Clamp-on-750-w-Bayonet-Lug-DEZ-1035-GB.htm
https://drontheim.com/product/fulton-armory-front-sight-base-clamp-on-750/
I haven't dealt with DEZ Tactical, but I have had good luck with Fulton Armory.
Don't cherry pick bud. Read the post in its entirety.
I did read your post.
I've found FSB taper pins some of the most difficult AR15 pins to remove. The dead blow hammer will make them even more difficult to remove should that ever be required.
That crap is not true and shows you do not understand what that method of adjustment is actually supposed to be doing. And then your post about it spreads the lack of understanding to others here...
Again - That method does not move the front sight base and is not supposed to. Before that thing (the FSB) even thinks about moving the index pin will be broken or serious damage will happen to its slot in the upper (or both).
I did read your post.
That crap is not true and shows you do not understand what that method of adjustment is actually supposed to be doing. And then your post about it spreads the lack of understanding to others here...
Again - That method does not move the front sight base and is not supposed to. Before that thing (the FSB) even thinks about moving the index pin will be broken or serious damage will happen to its slot in the upper (or both).
You’re truly a gem.
You’re truly a gem.
I know what you are not.
Please stop the snippy comments.
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