I am going to buying my first AR here in the weeks to come and need some basic information. I am wanting a carbine length rifle and gas system. Flat top receiver, heavy barrel, fixed stock and GI style front sight block/ post or whatever you call it.
My main question is what type of sight picture do you have with the front GI style sight post and a 3-9x40 scope mounted in one of the quick disconnected raised mounts?
Does the front sight post obstruct the view of the scope?
If anyone has any pics looking threw their scope with a front fixed GI post type sight please share them with me. I have not found anything similar on the internet.

The front sight won’t cause an issue, especially at higher magnification. I had never had experience with this until our daughter scoped up one of her AR’s this way. Sorry, I can’t help out with the sight picture through the scope. Thanks.

Bryan

If you were able to co-witness the sights, the crosshairs would be right at the top of the front sight post.

Many ARs do not have a built in fixed front sight. If there is a rail, fold down back up sights can easily be mounted. (Magpul has good backup sights.) They are normally folded down and only used as a backup. Scope mounts usually are tall enough to look over the front sight. if fixed. Co-witnessing is usually done with red dots without magnification.

When I bought my AR I was having a hard time trying to decide what I wanted. I decided to go with a Colt 6940 that came with flip up sights, then added a Vortex 1-4 x 24 illuminated scope and a Bobro quick disconnect mount. I figured if I could flip the sights down and leave them on the rifle and have the quick disconnect, it would make it easy to go back and forth. As for the scope I couldn't make up my mind between red dot or magnification, so I thought I made a good compromise.

I think that there will be no problems with the front sight, because the sights should be of good quality. However, if you are confused by the possible fact of the problem, you can install a folding device for the sight in the future. But I will tell you right away, use only high-quality accessories for a rifle that will fit and serve you for a long time, you can see them here ballachy.com. Also, always watch the reviews on YouTube and read the reviews, so as not to get a bad device. After you install it, you can stop worrying about something interfering with you. But be prepared for the fact that you will spend money, because high-quality products are expensive. But then you will be happy with the changes. I think I helped you and you will take my advice into account. Good luck to you!