Is the Colt higher than the Bushmaster or is the difference only in the front sight bases used by the manufacturer, F marked and non-F marked? Thanks.

I'm 99% sure that since Bushy does not use the "F" FSB that their carry handle is shorter than a Colt.  If you pair the wrong carry handle/FSB you will have trouble getting a zero.

Also - I'm pretty sure the BUISs that Bushy sells are also lower than "normal" ones.

One is mil spec.

The carry handles are the same.

The Bushmaster has a different front sight post  to allow it to work properly with the detachable carry handle.

Quoted: The carry handles are the same. The Bushmaster has a different front sight post  to allow it to work properly with the detachable carry handle.

I dont understand how that could be possible?

The carry handles are the same but the FSBs are different?    

So the Colt FSB will not work properly with the Colt detachable carry handle?  Is the height difference in the upper receiver then?  

Quoted: The carry handles are the same but the FSBs are different?

Correct.

So the Colt FSB will not work properly with the Colt detachable carry handle?

If it is 'F' marked it will.

Is the height difference in the upper receiver then?

No. The difference in height of the front sight bases.

Quoted: Quoted: The carry handles are the same but the FSBs are different?     Correct. So the Colt FSB will not work properly with the Colt detachable carry handle?   If it is 'F' marked it will. Is the height difference in the upper receiver then?   No. The difference in height of the front sight bases.

Thanks ripcode
I'm still not getting it.  If the Uppers are the same, the carry handles are the same and the FSBs are different - how can both rifles work properly?  

You are saying you can put a Bushy handle on a colt and a colt handle on the bushy and the 2 have defferent FSB heights - how can the line of sight be correct on both rifles?

forgive my ignorance on this but I'm missing something.

Quoted: Thanks ripcode I'm still not getting it.  If the Uppers are the same, the carry handles are the same and the FSBs are different - how can both rifles work properly?

The Bushmaster FSB uses a taller front sight post to make up the difference in height.

Get it now?

Okay, let me try to explain.

Colt=  regular sight post, taller F marked sight base

Bushmaster= taller sight post, regular sight base

That means that they give you the same sight picture with the same carry handles.  They just achieve that sight picture it in different ways.  

Edited for spelling errors.

Bushmaster carry handles are shorter then Colt/Mil-SPEC

Bushmaster does not use taller front sight posts on their flat top rifles and carbines. If you were to use a Colt carrey handle or MIL-SPEC BUIS on a Bushmaster flat top rifle or carbine you would have to use a taller front sight post.

Also, there is no apparent reason that I have found for Colt/MIL-SPEC removable carry handles and flat top FSBs to be taller than Bushmaster's non MIL-SPEC versions.

And yes, Colt's are "MIL-SPEC".  

$50

My "colt" grey CH is marked with the Anchor Harvey "splintered A" only.
My "Bushmaster" black CH is marked with the Anchor Harvey "splintered A" and an "A" batch code.
My "JTD" black CH is marked with the Anchor Harvey "splintered A" and a "B" batch code.

All are the same.

Quoted: My "colt" grey CH is marked with the Anchor Harvey "splintered A" only. My "Bushmaster" black CH is marked with the Anchor Harvey "splintered A" and an "A" batch code. My "JTD" black CH is marked with the Anchor Harvey "splintered A" and a "B" batch code. All are the same.

Are you sure your Colt removable carry handle is a Colt? Did you check the highth of the sight on the Colt handle and compare it to the others? It should be about .040 higher than the Bushmaster.

Colt and Bushy handles are exactly the same. Colt uses the F marked sight base and Bushy does not. Most people with A3 Bushies have had to purchase a .40 taller sight post in order to properly zero myself included, b/c Bushy DOES NOT equip the rifles from the factory with the taller post. I have e-mailed Bushy asking why they did not use the proper sight base and they gave me some BS. They said they would send me a tller post but I had already gotten one. When I asked why they didn't ship the rifles with the taller post they said it's usually not a problem. More BS. I have been totally pleased with Bushy's customer service other than on this issue. But hell the post costs like $4.

Quoted: Bushmaster carry handles are shorter then Colt/Mil-SPEC Bushmaster does not use taller front sight posts on their flat top rifles and carbines. If you were to use a Colt carrey handle or MIL-SPEC BUIS an a Bushmaster flat top rifle or carbine you would have to use a taller front sight post. Also, there is no apparent reason that I have found for Colt/MIL-SPEC removable carry handles and flat top FSBs to be taller than Bushmaster's non MIL-SPEC versions. And yes, Colt's are "MIL-SPEC".

This post is TOTALLY incorrect.

The FSBs are dimensionaly the same between both.Its the machined out part between both ears thats different.The Bushmaster shelf between the ears is lower  or standard than the shelf on a Colt wich the flat top needs.All bushy would have to do is machine the shelf a bit higher and use the standard post on their flat top carbines...problem solved.

Quoted: The FSBs are dimensionaly the same between both.Its the machined out part between both ears thats different.The Bushmaster shelf between the ears is lower  or standard than the shelf on a Colt wich the flat top needs.All bushy would have to do is machine the shelf a bit higher and use the standard post on their flat top carbines...problem solved.

Or just include the $4 .40 taller post. Then they wouldn't have to change their machining process for the flat top rifles.

If Bushmaster's removable carry handles are now the same highth as Colt's, that's new news to me.

Last I heard in an E-mail from one of Bushmaster's head gunsmiths was that their removable carry handles are .040 shorter than Colt's. Tweak, and I think Troy has also said that Colt/MIL-SPEC DCHs are taller then the rest.

Quoted: Quoted: My "colt" grey CH is marked with the Anchor Harvey "splintered A" only. My "Bushmaster" black CH is marked with the Anchor Harvey "splintered A" and an "A" batch code. My "JTD" black CH is marked with the Anchor Harvey "splintered A" and a "B" batch code. All are the same. Are you sure your Colt removable carry handle is a Colt? Did you check the highth of the sight on the Colt handle and compare it to the others? It should be about .040 higher than the Bushmaster.

Quoted: Quoted: Quoted: My "colt" grey CH is marked with the Anchor Harvey "splintered A" only. My "Bushmaster" black CH is marked with the Anchor Harvey "splintered A" and an "A" batch code. My "JTD" black CH is marked with the Anchor Harvey "splintered A" and a "B" batch code. All are the same. Are you sure your Colt removable carry handle is a Colt? Did you check the highth of the sight on the Colt handle and compare it to the others? It should be about .040 higher than the Bushmaster.

So you have not checked to see if there is a difference with calipers?  

Quoted: If Bushmaster's removable carry handles are now the same highth as Colt's, that's new news to me. Last I heard in an E-mail from one of Bushmaster's head gunsmiths was that their removable carry handles are .040 shorter than Colt's. Tweak, and I think Troy has also said that Colt/MIL-SPEC DCHs are taller then the rest.

That is some of the BS I was talking about from Bushy. Carry handles are forged by various sources ie Cardinal Forge, Anchor Harvey, etc.  for Colt, RRA, Bushy, etc. They are all the same. They dont make a slightly taller handle for Colt only.

You know, this topic gets covered about once or twice a week lately, and it's always in regard to flat top uppers and whose clamp on sight unit is what dimension.  What no one ever seems to acknowledge is  that ALL short barrel ARs, whether flat top or one piece uppers, need, and have always needed, a .040 higher front sight point.

My SP1 carbine, purchased in 1978, came with an .040 higher front sight post; and when I replaced it w/a current type square post awhile back I had to use the Bushie higher piece. My M4gery, with a Rock River upper and barrel, and a Bushmaster sight unit, needs an .040 higher front sight point, and since RR doesn't use an F marked base, it needs the higher Bushie post.

Now if SP1 carbine uppers, and non Colt M4 types all need a higher front sight point, I have a really hard time believing that Colt clamp on sight units are any higher than anyones elses current production pieces. And I really don't think that the Bushmaster employee who said that their clamp on units are lower than Colts knows what the hell he's talking about (if he even really exists).

So far as I can determine, if it's a carbine type, it needs a front sight tip .040 higher than a rifle; and it really doesn't matter if you build the higher surface into the front sight base (F Type), or the front post, as Bushie does now, and Colt used to do.  Until y'all are willing to address the realities, that short barrelled ARs need a higher front sight point, and stop arguing about if Colt rear clamp ons are higher than anyone elses, it's just an exercise in spinning wheels.

Carry handles are forged by various sources ie Cardinal Forge, Anchor Harvey, etc.  for Colt, RRA, Bushy, etc. They are all the same. They dont make a slightly taller handle for Colt only.

They only make the raw forging.  It's Colt, BM, RRA, whoever that does the final machining of the forging into the handle, so Colt can (and does) machine theirs differently than anybody else.

What no one ever seems to acknowledge is that ALL short barrel ARs, whether flat top or one piece uppers, need, and have always needed, a .040 higher front sight point.  ... My M4gery, with a Rock River upper and barrel, and a Bushmaster sight unit, needs an .040 higher front sight point, and since RRA doesn't use an F marked base, it needs the higher Bushie post.

Colt has used a narrower post on their carbines to compensate for them being closer, but as far as I know they're not a different height.  None of the other makers acknowledges (or knows about) that difference and uses the regular A2 post.  My RRA midlength upper works fine with the BM carry handle I have on it and no special post.  Since RRA doesn't offer a higher post that I know of I'm sure that the one it came with is the regular A2 post.


This topic was discussed a while back in a thread that ran several pages.  The story from the "knowledgeable people" like Tweak and Troy then was that the Colt flat-tops (any length) have the sight plane .040" higher than on fixed sight rifles.  (I'd love to hear the logic behind that decision...)  They get the extra height at the front by machining the flat part where the post screws in .040" higher and using the regular height post.  These are the "F" FSBs, and both the M4 and the M16A4 have it (meaning the M16A2 and M16A4 barrels are different part numbers, because they differ in that one dimension).  Bushmaster and everyone else did the logical thing and used the same FSB for all of their rifles, A2 or A3, and their handles are .040" lower than Colts to match.

The problem comes in when people start using the BUISs like the ARMS#40, GG&G, Troy, LaRue, LMT, etc. that are designed to work with the "F" height FSB on the military rifles on their BM, RRA, etc. rifles with the lower sight plane.  BM's solution to this is the .040" taller post, which puts the top of the post in the same place with respect to the ears as the regular post in the "F" FSB.  

All of this is complicated by the fact that individual rifles zero with the post in different places and some are able to zero with the mis-matched heights and some aren't, so when you tell somebody who can't get his to zero that he needs a taller post somebody else will jump in and say "mine worked fine".

OK unbelievers, this is straight from Bushmaster's site:

www.bushmaster.com/faqnew/content_by_cat.asp?contentid=153&catid=95

Will the Bushmaster V-Match upper receiver accept the Colt Detachable carry handle?   (published: 7/25/2003 12:22:20 PM)  

Article # 153  

Our V-Match (flattop) receivers will accept the Colt carry handles - however, the Colt barrel as installed on their upper has a front sight that is about .040" higher than mil-spec. This can cause an elevation problem when using mis-matched parts. The Colt handle will only work with a Colt match barrel. The Carry Handle that we are introducing will work with anyone's barrels (except the Colt Match barrel). Call us at 1-800-998-SWAT to order the new Bushmaster Carry Handle.  

Quoted: What no one ever seems to acknowledge is  that ALL short barrel ARs, whether flat top or one piece uppers, need, and have always needed, a .040 higher front sight point.

Wrong.

Quoted: Colt has used a narrower post on their carbines to compensate for them being closer, but as far as I know they're not a different height.

Well Bubba, you just don't know! So I'll tell you what I'll do. You send me $5.00 (.50 for postage and $4.50 for my time and trouble) and I'll send you the original round front sight post I pulled off that 1978 built Colt SP1 carbine, and you can measure the damn thing yourself.  It is exactly .04 higher than the round A1 sight blades I took off the Milsurp rifle uppers; when I changed them all over to square posts.  Yes, it's also narrower, to compensate for being closer to the eye.

Your experience w/a midlength is completely irrelevent. It has a rifle length sight radius, so of course it's going to use a rifle height blade.

If you sense irritation in this post, you are spot on. First, I recall no post by either Tweak or Troy, disputing the fact that short barrel ARs need a higher front sight, though I freely admit that I haven't read everytrhing they've ever posted.

Second, when you use information supposedly posted by someone else, to tell someone who has owned one of the pieces for over 25 years and has done the measurements that he's wrong, you're telling me that I'm a liar, or an idiot who cannot read a micrometer.  And that I do not take kindly.

Finally, to settle this "Colt sight units are mounted higher on the base than aftermarket" hooha, will some of you who own own Colt detachable sight units PLEASE measure the distance between the bottom of the base, and the shelf of the sight cutout, so that we can settle this latest in a long series of assertions about why Colt uses the F marked front sight base. I say latest, because in the past year I seen claims that Colt uppers have a thicker top on the upper itself, Colt has a thicker base on the sight unit, and most everything else imaginable. Everything up to, but not yet including, "Witches put a curse on Colt sight units, and that's why". Maybe that's next

I haven't kept count of how many members have written post about needing a higher front post point on their Bushmaster, Rock River, and other brand carbines, but it's been a bunch over the years. Sure seems strange that the "Colt rear sights are higher" crew keeps on chanting the same old mantra.  And none of them ever posts an actual mmeasurement.

Quoted: Quoted: What no one ever seems to acknowledge is  that ALL short barrel ARs, whether flat top or one piece uppers, need, and have always needed, a .040 higher front sight point. Wrong.

POST PROOF!

Quoted: Quoted: Quoted: What no one ever seems to acknowledge is  that ALL short barrel ARs, whether flat top or one piece uppers, need, and have always needed, a .040 higher front sight point. Wrong. POST PROOF!

No carbine length A2 ARs that I know of ship with .040 higher sight posts, and nobody that I know of with a carbine length A2 AR has had trouble getting a zero with the normal sight post.  I have only seen trouble on flattops with non "F" marked FSBs and "mil spec" iron sights installed.  The "F" FSB is taller than the normal FSB, why is this so hard to understand? Bushy chose to use the normal FSB on their flattop models while colt uses the "F" FSB just like they ship to the military.  The rear sights must match up accordingly.

...Well Bubba, you just don't know! So I'll tell you what I'll do. You send me $5.00 (.50 for postage and $4.50 for my time and trouble) and I'll send you the original round front sight post I pulled off that 1978 built Colt SP1 carbine, and you can measure the damn thing yourself.  ...

I'll take your word for it.  We were talking about the current square posts, which may be different than the round ones, and if it's almost as old as me there's no telling what might be different.  Especially with Colt.

Your experience w/a midlength is completely irrelevent. It has a rifle length sight radius, so of course it's going to use a rifle height blade.

Acutally the sight radius on a midlength is shorter than the rifle sight radius (16-3/4" vs. 20-1/8").  I believe that's actually closer to the CAR length than the rifle length.

If you sense irritation in this post, you are spot on. First, I recall no post by either Tweak or Troy, disputing the fact that short barrel ARs need a higher front sight, though I freely admit that I haven't read everytrhing they've ever posted.

The eariler discussion that I was referring to made no distinction that I can recall about the different sight radius, only between the flat-top and fixed sights.   IIRC it was Tweak that provided the information about the heights and from his other posts here he seems to know what he's talking about.  All of my ARs are non-F and mid-length or longer, so I can't measure myself.

Second, when you use information supposedly posted by someone else, to tell someone who has owned one of the pieces for over 25 years and has done the measurements that he's wrong, you're telling me that I'm a liar, or an idiot who cannot read a micrometer.  And that I do not take kindly.

I believe you that your 1978 SP1 Carbine round post is longer than your A1 round post.  I have not not the measurements myself so I must be wrong.  Can you measure a Colt A2 post, a Colt M4 post, an M16A4 post, and a BM post for us?

Finally, to settle this "Colt sight units are mounted higher on the base than aftermarket" hooha, will some of you who own own Colt detachable sight units PLEASE measure the distance between the bottom of the base, and the shelf of the sight cutout,

I only have a BM handle, but I'll try to measure it this weekend.

My Bushmaster detachable handle measured .793" between the bottom surface that mates to the top of the rail and the top surface that the sight base bottoms down against.  Measured at the very rear of the sight base, just behind it and behind the attachment clamp part.

Who has a Colt handle they can measure?

well now this sparked my interest. im getting a Bravo Company Govt profile 20" upper and putting a RRA carry handle on it. is there a height difference in that?

If this is the upper you're getting, then it says:

These are built with ... the proper Mil-Spec taller F-marked forged front sight base.

Your RRA handle would be designed for the shorter front sight base, so you do have a mismatch.  In your case the front sight post would need to be shorter than standard, which I don't think anybody makes.  But it would be easy to shorten a stock one if you needed to.  You probably can zero it anyway, but the front post might be pretty low in the base.

yup, thats the upper. i dont have any experience with ARs, so i wouldnt go trying to shorten something. is there another handle that will be good?

EDIT: Does the DPMS A3 Carry Handle w/A2 Sights work, or what about the LMT Detachable Carry Handle Assembly, it says its made to Mil-Spec. I did not realize this was going to be a problem. If neither work, what back up flip iron sights can i put on to get a good zero?

Quoted: My Bushmaster detachable handle measured .793" between the bottom surface that mates to the top of the rail and the top surface that the sight base bottoms down against.  Measured at the very rear of the sight base, just behind it and behind the attachment clamp part. Who has a Colt handle they can measure?

Here are the measurements from four different Colt DCHs originally posted by Ekie in one of Tweaks threads. Measured the same way you measured yours. The measurements of all four Colt handles are .832 and yep, there is a difference.  

EDIT: Does the DPMS A3 Carry Handle w/A2 Sights work, or what about the LMT Detachable Carry Handle Assembly, it says its made to Mil-Spec. I did not realize this was going to be a problem. If neither work, what back up flip iron sights can i put on to get a good zero?

DPMS A3 handle would be the same height as the RRA one.  (And BM too--I have a BM handle on my RRA upper.)  LMT is probably the same as Colt so it should work.  Assuming you don't have the handle yet, and you're not really hung up on the handle (vs. a BUIS), then I'd go for one of the "military" BUISs like the ARMS#40 line, Troy or LaRue.  Then you could put an Aimpoint on later.

If you already have the RRA handle, then I'd try it before I spent money on anything else.  It might work--some guns are OK w/o the tall post.  Or you might be able to adjust for it at the rear sight.

Quoted: yup, thats the upper. i dont have any experience with ARs, so i wouldnt go trying to shorten something. is there another handle that will be good? EDIT: Does the DPMS A3 Carry Handle w/A2 Sights work, or what about the LMT Detachable Carry Handle Assembly, it says its made to Mil-Spec. I did not realize this was going to be a problem. If neither work, what back up flip iron sights can i put on to get a good zero?

LMT, CMT/STAG, and Colt, all make milspec DCHs.

Well well well, who would have thought that the Colt and Bushy carry handles would differ by almost exactly .040" ....  TOLD YA!!

Quoted: Well well well, who would have thought that the Colt and Bushy carry handles would differ by almost exactly .040" ....  TOLD YA!!

Yeah, and people were rolling their eyes at me when I said there was a difference. Now I get to rolleyes at them, THERE, TAKE THAT!!!

Damn, I had to measure my carry handles... 2 of them are Cardinal Forges and 1 is Anchor Harvey.
Other Cardinal came with Bushmaster Patrolman´s Carbine and the other came from Brownells and was sold as DPMS.
Anchor Harvey was also bought from Brownells as Prairie River Arms.

#1 Cardinal (Bushy) handle .7925"
#2 Cardinal (DPMS) handle .7935"
#3 Anchor Harvey handle .8325"

.8325" - .7935" = 0.039" (close enough).

MN

Does Prairie River Arms supply to the government?

Why don't you just adjust the front sight post?  I think about 1.5 to 2 full turns moves the front sight post up 0.040"

T

Because in many cases raising the standard height post that much raises the base above the milled flat so it's barely in.  

WOW... I guess I'm either lucky or have pleased the tolerance Gods. hanks
T

someone said that the RRA handle wouldnt work with the BCM govt profile 1/7 barrel. i emailed eaglefirearms.net asking them to take off the handle from my order because of this, but they said it would work because it is milspec....?

E-mail from Bushmaster.

    Subject: Sight Heights

    "When Colt came out with the A3 design with the detachable carry handle they made the front and rear sights .040" higher than the sights used on A1 and A2 rifles. The front sight forging is the same but the front sight post when set for mechanical zero is even with the top of the sight ears instead of below them as the plane for the sight post is milled higher. You will notice on 20" A3 barrels there are two raised bands on the barrel under the handguards. This designates that the barrel has the front sight base with the front sight that is milled high for the front sight post. Colt parts lists have a different part number for the higher front sight base barrels and sight bases for A3 and M4 barrels.
   
    We decided when we began to build the A3 models with detachable carry handles that we would keep the sight heights the same for all models. Our A3 handle, Flat-Top Rear Sight and Rear Flip Up Sight has the same rear sight apertuer height as on the A1 and A2 receivers so that all barrels with standard height front sight bases will interchange. The Mark Brown Flat Top Mount also uses this same rear sight height.

    The A.R.M.S. Swan Sleeve, #40 Flip Up Rear Sights, Colt A3 handle and G.G. & G. have the higher rear sight aperture height. When used with standard height front sight bases the front sight post must be turned out to the .040" higher position where it is even with the top of the sight base ears for mechanical zero.

    We now carry a .040" taller front sight post, part number 9349056-M for $4.95, to correct this difference.

    I do not know why they changed the elevation of the sights on the A3 models. You would have to ask them why it was done if you can get a response from them."

    Jim Eden, Tech Support

Quoted: someone said that the RRA handle wouldnt work with the BCM govt profile 1/7 barrel. i emailed eaglefirearms.net asking them to take off the handle from my order because of this, but they said it would work because it is milspec....?

What does "BCM" stand for ("B"ushmaster "C"hro"M"e)

no, Bravo Company Mfg, heres the link to the upper im talking about

www.bravocompanyusa.com/Standard20inchRifleUppers.html

OK...I measured my four DCH's and two of them measure the taller (mil-spec) .832.  At this point, how does one verify the manufacturer if not already known? Can this be determined by the forge markings? One of my mil-specs has a splintered "A" followed by another "A", and this one I was told was off of a Colt rifle. The other mil-spec handle is from an unknown source, and has what appears to be a "A-l" with no space between the letters and the dash, and is enclosed in a circle. Is this the Anchor Harvey forge? Both mil-spec handles have their forge markings on the left side just forward of the sight, while my other two non mil-spec handles have their markings on the right side. So is the first one likely to be from a Colt rifle, or could it be from any other rifle using a mil-spec handle...or maybe it really doesn't matter???

Thanks,
...old and confused

Quoted: no, Bravo Company Mfg, heres the link to the upper im talking about www.bravocompanyusa.com/Standard20inchRifleUppers.html

The link says the upper your talking about has the taller F marked FSB. I don't think RRA's DCH is milspec. So I would get a Colt or CMT/STAG DCH in order to be compatible.    

OK....I'm not that knowledgeable in this area, so bear with me.  I have a Rock River Entry Tactical that came with the tactical detachable carry handle.  I would like to replace it with a removeable carry handle.  Will a Rock River carry handle work, or will I still need to install a .040 sight post?  How about if I go with a Colt or Bushie?  Thanks a bunch!

Quoted: OK....I'm not that knowledgeable in this area, so bear with me.  I have a Rock River Entry Tactical that came with the tactical detachable carry handle.  I would like to replace it with a removeable carry handle.  Will a Rock River carry handle work, or will I still need to install a .040 sight post?  How about if I go with a Colt or Bushie?  Thanks a bunch!

Since your rifle is a Rock River you don't have the taller F marked FSB and the RRA DCH will work and so should the Bushmaster DCH, but not the Colt as it is a taller milspec DCH. So if you use the RRA or Bushy DCH with your standard FSB there should be no need for the taller .040 FSP.