In order to obtain clear enough dot instruction at quite long work distance, nothing can be comparable with Berlinlasers high power pro red dot laser alignment. It is a quite advanced 635nm red laser tech applied dot measuring tool. When this red laser module is available with wide range output power of 150mW to 500mW, and equipped with good TEM00 laser beam mode, it is just achieving the most accurate and the clearest dot instruction under long distance positioning fields effectively.
Supported by 9V DC input power supply, high power pro red dot laser alignment is getting constant electric power source and continuous red reference dot targeting from laser beam aperture. It is accepting wide range electric current within 100V to 240V, providing quite convenient and accurate red reference dot targeting for majority countries and regions on the earth. This compact structure made red laser module is easily installed and adjusted, and then achieving no mistake dot instruction for all mechanical processing works perfectly.
http://www.berlinlasers.com/pro-red-dot-projecting-laser-alignment

This is a great solution that can speed up aiming, especially when moving or off the hip. I think it will be useful for you to combine this with other devices. One of them is well described in this article https://outdoorfact.com/how-to-choose-the-best-red-dot-sights-for-ar-15/