^

A1 has a round front sight post and the A2 is four-sided...ie. squared off.  Is that what you are looking for?

dvo

Also the A1 tapers off towards the top.  The A2 is straight.

The A3 has four flat sides like the A2, but tapers off like the A1.

thanks, what I was looking for..............007

A1 has 5 clicks per rotation, A2 has 4.

A1 can be zeroed more precisely, but A2 has less shadow/reflection and is easier to focus on in some conditions.

Also the A1 has 5 clicks per revolution, the A2 only 4.



Lonny

Quoted: Also the A1 tapers off towards the top.  The A2 is straight. The A3 has four flat sides like the A2, but tapers off like the A1.

A3?

The only A3's I have seen all had A2 front sight posts, same as the A4.

Or is this some designation for the civie market again?

how 'bout a pic?

Quoted: A3? The only A3's I have seen all had A2 front sight posts, same as the A4. Or is this some designation for the civie market again?

I don't know!

If I can get a pic tonight, I'll post it.  It came on my LE Colt AR15-A3 Tactical Carbine.  I had it for years before I really even noticed it.  I'll bet there's a bunch of guys with them and don't even know it cuz they're too busy puting optics and shit on their guns!

I looks pretty much like the A2 site except it tapers towards the tip.

Quoted: Quoted: A3? The only A3's I have seen all had A2 front sight posts, same as the A4. Or is this some designation for the civie market again? I don't know! If I can get a pic tonight, I'll post it.  It came on my LE Colt AR15-A3 Tactical Carbine.  I had it for years before I really even noticed it.  I'll bet there's a bunch of guys with them and don't even know it cuz they're too busy puting optics and shit on their guns! I looks pretty much like the A2 site except it tapers towards the tip.

it's scary how many folks put optics on and never zero their irons.

I just looked it up - looks your rifle is like the civi semi-auto only version of the m4A1.  Does or has Colt used "A3" for any 20" barrel models?  I thought maybe the taper might be to compensate for the shorter sight radius - I know I have been known to put national match front sight posts in my carbines for that reason.

Of course, that wouldn't explain why the M4 has the same front sight post as the M16A2 - or maybe it doesn't?  I might have to make a trip to the arms room.

"A3" in Army terminology is just a full-auto version of the A2, I don't even think it has a flat-top upper, but I admittedly haven't seen one since 1997.

I'm not sure what other weapons this sight post was used on.

You bring up many good points.  Take that trip to the arms room and let us know.

I got my gun in 97 or 98 if I remember right.  It was before Colt had a separate "Defense" division.
My weapon is basically the LE6721 model.

I pretty much zeroed it and put it in the back of the safe.  Only a few months ago did the light bulb go on when I was dry firing.  I said "WTF...  this sight is different!"

Quoted: Quoted: A3? The only A3's I have seen all had A2 front sight posts, same as the A4. Or is this some designation for the civie market again? I don't know! If I can get a pic tonight, I'll post it.  It came on my LE Colt AR15-A3 Tactical Carbine.  I had it for years before I really even noticed it.  I'll bet there's a bunch of guys with them and don't even know it cuz they're too busy puting optics and shit on their guns! I looks pretty much like the A2 site except it tapers towards the tip.

What do you think of the A3 Tactical Carbine model?  I have a complete lower from that rifle and have wondered if I should seek out an upper to match it up.  Right now a Colt HBAR upper is mated to it.  Too heavy for my tastes.  Thanks,

dvo

Quoted: I'm not sure what other weapons this sight post was used on. You bring up many good points.  Take that trip to the arms room and let us know. I got my gun in 97 or 98 if I remember right.  It was before Colt had a separate "Defense" division. My weapon is basically the LE6721 model. I pretty much zeroed it and put it in the back of the safe.  Only a few months ago did the light bulb go on when I was dry firing.  I said "WTF...  this sight is different!"

Just got back from the arms room - all of our M4's have the same site post as the M16's - I figured as much, since I only remember there being only one NSN to order them for both, but you had me wondering.

Now, I am wondering why Colt tapered the site posts for your rifle - and if they sell them as parts - I might want one!

Quoted: What do you think of the A3 Tactical Carbine model?  I have a complete lower from that rifle and have wondered if I should seek out an upper to match it up.  Right now a Colt HBAR upper is mated to it.  Too heavy for my tastes.  Thanks, dvo

It is the 1/9 HBAR.  That's what comes on the AR15-A3 tactical bean!

Quoted: Now, I am wondering why Colt tapered the site posts for your rifle - and if they sell them as parts - I might want one!

I'll get a pic up tonight.  

S.A.W. lists it as....

FRONT SIGHT POST (SHORT TAPERED) CARBINE  $8.50

I'm assuming the "short" refers to the "F" stamped front sight base that matches to the FLAT TOP upper receiver.

Quoted: Quoted: I'm not sure what other weapons this sight post was used on. You bring up many good points.  Take that trip to the arms room and let us know. I got my gun in 97 or 98 if I remember right.  It was before Colt had a separate "Defense" division. My weapon is basically the LE6721 model. I pretty much zeroed it and put it in the back of the safe.  Only a few months ago did the light bulb go on when I was dry firing.  I said "WTF...  this sight is different!" Just got back from the arms room - all of our M4's have the same site post as the M16's - I figured as much, since I only remember there being only one NSN to order them for both, but you had me wondering. Now, I am wondering why Colt tapered the site posts for your rifle - and if they sell them as parts - I might want one!

I strongly suspect that the M4s in your Arms Room all have "F" marked front sight bases; which was brought out precisely because the services didn't want to have two heights of front sights to deal with.  Markm almost certainly has a standard sight base on his piece, which means that Colt had to use the higher post, which they had been doing ever since the Viet Nam issue XM177s, the SP1 carbines, and every other carbine type they ever put out prior to the F marked base.

Now Colt has "announced" that the higher front sight point is strictly for their flat tops with THEIR sight assy.  They've even convinced much of the after market producers like Bushmaster that this is true.  I recently was unable to convince one of the Bushie people that my SP1 carbine came w/a higher post in 1978, and that my M4gery, with a Bushie sight assy needed the higher point.

Thank you Markm for pointing out that the pre F base carbines all had higher front posts.  BTW the Colt part number for this piece is SP64665 and is listed as "Sight post front, 16" barrel"

Hey, but don't listen to me  The "experts" on this site have all decided that higher front sight points are only for those with Colt flat tops and Colt sight assys; and like the shnook at Bushie refuse to believe that Colt carbines, whether flat top or one piece uppered, have always come with a higher font sight point.

Believe what y'all want the truth is still the truth.

Early front sight post was round.  One 360 degree rotation equaled 5 MOA, one click equals 1 MOA (with a 20" barrel):



Current square sight post used on the M4, M4A1, M16A2, M16A3 and M16A4.  One 360 degree rotation equaled 5 MOA, one click equals 1.25 MOA (with a 20" barrel):



As mentioned, my understanding is that Colt 5.56 Carbines without the US property markings use a different front sight post then the standard USGI part.  Never noticed on my MT6400C's in that I sold the barrels off those.  My Colt 653 front sight posts are similar to the old A1 style but much taller.

Here is a half assed pic of the sight in question.

(the one on the right)

Quoted: I thought maybe the taper might be to compensate for the shorter sight radius - I know I have been known to put national match front sight posts in my carbines for that reason.

You might be right!

I held the sight on my A3 up to a standard sight post, and the tip of the sight is noticably smaller.

Colt uses tapered square posts on their comerical carbines.

It give the same sight picture as a 20" rifle.