Question from newbie

[philinmedford]

Ok, I've got a question that must be so obvious that I can't find it anywhere because it falls under the category "everyone knows that". I'm having a AR-15 built and it has a A3 flattop with T marks. I'm thinking of putting a red dot scope on it. Here's the question. Do I need to mount something on the top, or can I just mount it on there? All I've ever used is weaver mounts but just "eyeballing" it I don't see how weaver mounts would work. Will picatinny mounts be what I'm looking for? I appreciate any help in this matter.

[Iraqgunz]

Phil,

Many red dot type scopes (of quality) usually include some type of mount. My ACOG had a TA51 flat top mount included. The EOTech has a built in mount base. Aimpoints also have a standard mount included if I am not mistaken.

The T-marks are also known as rail addresses and they are there to assist you relocating an item in the same place in the event that it must be removed.

There is a difference between Weaver and Picatinney dimensions. The Picatinney or M1913 rail was designed to provide a standardization of dimensions for mounting accessories.

I highly recommend that you do not buy a piece of shit optic. They are generally expensive, but you get what you pay for. No matter what some clown at the local gun shack tells you do not skimp on the sight.

[philinmedford]

Thanks for your input. I understood or knew most of what you are saying except for this part. I was looking at the Aimpoint (for example) and it says this:

"Aimpoint Weaver-Style rings have a .139" wide square rod in the base of the ring that will fit a Weaver base or a Picatinny rail."

Ok, so I don't attach the scope directly to the top of the A3? I purchase either a Weaver base or a Picatinny rail and then attach THAT to the flattop?

Is there an advantage to either? I don't have or want a carry handle so that isn't an option.

[John_Wayne777]

Thanks for your input. I understood or knew most of what you are saying except for this part. I was looking at the Aimpoint (for example) and it says this:

"Aimpoint Weaver-Style rings have a .139" wide square rod in the base of the ring that will fit a Weaver base or a Picatinny rail."

Ok, so I don't attach the scope directly to the top of the A3? I purchase either a Weaver base or a Picatinny rail and then attach THAT to the flattop?

Is there an advantage to either? I don't have or want a carry handle so that isn't an option.

The A3 model upper receivers have a built in picatinny rail that the carrying handle attaches to:



That is a flat-top receiver without the carry handle mounted. As you can see, I have an iron sight mounted directly to the upper receiver. You don't need to manually install any rail space, as it's already machined into the top of the receiver.

To mount something like an Aimpoint to your upper receiver, you can use the mount that Aimpoint includes in the package with their optic and you can mount it directly to the top of the receiver. These are pictures of the mount that Aimpoint includes in the package. In the pictures I have the mount installed on an Ultimak rail for my VEPR-K, but it will mount the same way on the upper receiver of your AR:




The only downside to that approach is that the optic will sit too low to co-witness with iron sights. For that reason many will encourage you to invest in a good LaRue mount for your Aimpoint so you can use your iron sights as a backup to the optic. This is what a co-witness looks like, again using my AK:

[philinmedford]

John Wayne:

Thanks for that input. I think I understand now. A riser of some type is better than just mounting to the top.

Thanks to you also, I hate to seem so dumb about this but all I've owned are handguns and rifles that you just mounted a weaver mount on lol

[John_Wayne777]

John Wayne:

Thanks for that input. I think I understand now. A riser of some type is better than just mounting to the top.

Thanks to you also, I hate to seem so dumb about this but all I've owned are handguns and rifles that you just mounted a weaver mount on lol

Happy to be of assistance.

Thankfully with the A3 style upper receiver you won't need to worry about buying a mount and rings like on a Remington 700 or Marlin 336.

As for the "riser" issue, a mount like this one:



Will securely hold the Aimpoint in place to maintain zero. It can also be removed easily and if you put it back in the same spot you removed it from, the optic will still be perfectly zeroed.

It will also let you see the iron sights in the lower 1/3 of the optic, whereas the mount included in the Aimpoint package will not. In fact, if you have a standard front sight base on your AR the included Aimpoint mount will be useless as it sits so low that the front sight base will end up taking up the full center of the optic. If your AR doesn't have a standard front sight base then you can use the included Aimpoint mount if you don't care about iron sights. (NOTE: You should always have irons on a carbine meant for serious social purposes...)

[philinmedford]

Again, many thanks. The AR I'm having built (by Grant btw) comes without a trigger so I've been looking at the pro's and con's of getting a chip mccormick or timney drop in vs just using a standard trigger. I've seen posts regarding both....

I just ordered some of those Lancer L5 magazines from a vendor here on the marketplace, they looked like a good thing to have.

I really enjoy going to the range and can only anticipate that it will be per usual when I get into a new realm of firearms - you know the feeling that you hope your bank account will be able to support your enthusiasm.

[Outlander Systems]

Apoloigies for going off-topic:

John, how do you like that rear sight?

I'm debating between the LMT, LaRue, and Troy as backup options, and I'm back and forth. For the particular rifle I'm mounting it on, the front sight is the standard M4/AR type. When I'm shooting I usually prefer the flip ups I have on my other blaster to stay up anyway, so having fixed irons doesn't turn me off.

Decisions, decisions...

[Outlander Systems]

Phil: in regards to the bank account -

I've come to the realisation that saving up, being patient, and buying as per the recommendations from our fellow M4carbine.net users, will always pay off.

Everyone here is exceptionally helpful, and several members here have steered me in the right direction. Sometimes it's tough medicine to swallow, but it'll almost always invariably help you out in the long run.

M4carbine.net is a breath of fresh air, coming over here from TOS. The folks here are a no-nonsense, utilitarian bunch, who've been there, done it, and all they got was a lousy keffiyeh.

[LettersFromEarth]

...M4carbine.net is a breath of fresh air, coming over here from TOS. The folks here are a no-nonsense, utilitarian bunch, who've been there, done it, and all they got was a lousy keffiyeh.

Come on and just admit that you dont care for TOS is because I dont post there!!! :P