It’s been a long time since every AR15 came with built-in iron sights; today, every professional has some kind of optic – often an ACOG – on top of their weapon. There are plenty of good reasons for that, too. A quality optic will give you a brighter sight picture in low light, increased accuracy and quicker target acquisition at medium and long range. For an infantryman or law enforcement marksman, it’s a huge step forward in capability. If you’re relying on iron sights, you’re putting yourself at a huge disadvantage.
So let’s talk about why you need a set anyway.
Most AR15-style rifles now come with a flat top and 1913 rail, ready to take your choice of scope. A lot of them include a set of Picatinny-compatible iron sights in the package, though, and that doesn’t just apply to civilian rifles – even the US Army’s SOPMOD kit for the M4A1 comes with a rearsight to go with the built-in military foresight. If you’re doing anything more important than plinking in the back field, you should never go anywhere without a quality set of iron sights fitted to your rifle and ready to use.
Modern tactical optics are compact and robust, but the simple fact is nothing is indestructible. A sharp blow in the wrong place can crack or shatter lenses, or break your scope’s adjustment turrets. Mounts can go wrong too – a bad screw or snapped clamp can leave the actual scope intact, but useless. Without a way to aim it accurately, your weapon will then be next to useless, too. That’s where backup iron sights (BUIS) come in.
“You should never go anywhere without a quality set of iron sights fitted to your rifle and ready to use.”
There are two types of BUIS: fixed and flip-up. They vary from simple fixed rear notches to more complex ones with multiple range settings, but what they all have in common is they’re light and compact. If your scope is damaged or there’s some other reason you can’t use it – some climate conditions seem tailor-made to fog lenses – you just remove it and switch to the iron sights. You’ll lose some performance, but a lot less than if you were left with no sights at all. Obviously it goes without saying that BUIS need to be strong, and some of the cheap ones don’t inspire confidence. There’s nothing on your weapon that’s a good candidate for scrimping on pennies and that goes double for the sights – buy the best you can.
Fixed or flip-up? Both have advantages. Flip-up styles won’t interfere with the field of view of your scope (more of a problem with nonmagnified optics) but they’re more complex and take longer to deploy. Remembering this is a backup, the simplest option is a good set of fixed sights. They’re stronger, and ready to go as soon as the scope’s off the rail. Avoid complex or large adjustment knobs; they just get in the way and make it more likely the sights will lose zero.
Good zero is vital for your BUIS. Make sure they’re properly dialed in and then locked; after that you can get on with zeroing the scope and forget about them until they’re needed. It’s best to zero them at 100 yards; the flat trajectory means you’ll be hitting close to point of aim out to the effective range of the weapon. Before zeroing, make sure all mounting screws are tight; Loctite them if you can, then leave the sights on the weapon. If you absolutely have to take them off, zero them again afterwards. It’s easy to skip this and justify it by thinking they’ll only be used in an emergency, but if you think about it, an emergency is when you really need to make every shot count.
Disclaimer: The content in this article is the opinion of the writer and does not necessarily reflect the policies or opinions of US Patriot Tactical.