“Don’t mount an optic on your AR-15’s handguard!” That’s what a lot of folks on the Internet – and IRL – will tell you. But is it true? Brownells Gun Techs Caleb and Steve say the answer is a qualified “yes”. The receiver and the handguard are two separate components, with the ‘guard clamped to the barrel nut or attached some other way. The handguard can flex independently from the receiver, causing a measurable deviation in point of impact (POI) from point of aim (POA) if there’s an optic mounted on it. The size of the shift will depend on the stability of the handguard. If it’s a sturdy one by, for example, Geissele or Midwest Industries that solidly clamps to the barrel nut, flex will be minimal, and an optic mounted on it will work just fine, unless you’re shooting at very long ranges. A MONOLITHIC upper with the receiver and handguard machined from a single piece of aluminum is an even solider platform for an optic. But a cheap, two-piece, drop-in, quad-railed replacement for the military-type plastic handguard is definitely not stable enough. So the “myth” is NOT a myth. There CAN be problems with mounting an optic on your AR-15’s handguard, though in certain circumstances they are so minimal that a handguard-mounted optic can do its job just fine.
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Caleb's shirt is as shiny as his hair.👍👌👏👊
Love this series.
The only time I mount an optic on the upper and the rail is just to initially get the hand guard straight. After that, keep it on the receiver from that point forward.
I'd venture to say that for most shooters, the tiny loss of accuracy will never be noticed. The rifle may be sub MOA, but the operator is minute of coffee mug.
Plebs! Don’t bridge your optics!
Run it on the start of the hand guard where the receiver ends but not touching the receiver
I honestly enjoy this series. Information is always there, you just need to know where to find it, and determine if it's true. You guys do amazing work. Would love to see more "Smyths" on the AK and AR platform.
I completely understand your point in terms of bridging the gap between the upper receiver and the handguard, especially if your mount is 2 separate rings. However, my front sights are all mounted at the end of the handguard. I’ve been considering a scout scope (intermediate eye relief). That particular rifle has alignment tabs for the handguard and it’s pretty rugged.
I'm sure the Taliban are starting to watch these videos now.😐
Geesh pretty boy ditch the sideburns and Vaseline!
But, backup front sights at the far end of the hand guard is just fine though? I guess a shifted POI in an optics failure scenario, is better than no sights at all. Still going to be some shift if the hand guard is impacted either by being "bent", or by being used as a steadying support.
why not?
I mean, I guess I never thought of this as a myth. The best place to mount a scope is on the receiver area, any where else you run a higher chance of optics shifting. However, I do personally like forward mounted optics, I just whish there was a solid way to mount them without issues later on.
Excellent advice. I learned another useful building tip.👍
I can’t find any reason for WD-40 usage in this one..
Where's that front site mounted… ?
Does that mean your backup iron on the front of that rifle is not reliable?
I've noticed people who tell you that you shouldn't have a scope mounted on the handguard usually have a front sight mount all the way at the end of their handguard.
Question about lasers and such: Do military rifles experience less shift because the top handguard is secured to the front sight post/gas block assembly?
It seems like that would make the front end of the handguard more stable than a free-floated handguard that only attaches at the barrel nut. Or at least bring the shifting of the handguard more in line with the shifting of the barrel itself.
why have your flip-up front sight mounted there then if its bad idea…
Reason I don't mount anything on the receiver and the handguard is heat… heat causes expansion. receiver will expand at a different rate then a handguard. take one of those el cheapo harbor freight point and measure thermometers and measure the heat differences of the receiver and the handguard where the barrel nut is after say 10-15 rounds heat things up.
Chinese handguards? I got plenty of cheap American shit already.
LMT monolithic 😉
Thanks guys. This is one I’ve always had questions and doubts about.
Check out ‘The Social Regressive’ he testes it all out.
Inrange did a test with a visible laser on an mr556 handguard and there was a significant shift with pressure applied
Like button: smashed
heck I agree I always thought that is one of the reason you had a full length top rail, encase you needed the room for optics and other mounted gear/equipment, I mount my optic wherever zI think it suites me best, because it pretty much takes an act of God to move out of alignment anyway I put my handrails through heck and back and they are still solid and have not moved out of alignment
targeting the r/plebianar today, I see
I saw somebody with a scope mounted half on reciever and half on handguard. I asked him why, he said to keep the handguard from slipping off. 🤷♂️
That's why they make cantilever optic mounts, to account for long optics with short eye relief.
Most people are mounting optics on the handguard or "bridging" out of pure ignorance. Some things aren't free to explore one's personal preference.
I have a Aero Precision COP C4 monolithic upper and I still see no reason to mount an optic forward of the receiver area. I also have several AP M4E1 uppers with handguards that screw and torque down to to the upper barrel nut extension. There's no way that mounting style can flex or rotate, but I still wouldn't mount an optic that far forward.