Carbine Guys.... Height Over Bore/Tall Sight Risers

[Blaster229]

Risers are taller nowadays for good reason. You get faster acquisition and better field of view from them.
So you zero your rifle at whatever distance you do it, but what happens when you get within 7-10 yards at CQB distances? Your dot is 3 inches above bore. That dot is not where your round hits.
DJ and Mike Glover explain height over bore at close distance. Vital info for if or when you might take a hostage shot. Could be fatal to a loved one if you use a carbine for home defense.
Perfect example are those funny videos where guys put a round through their truck beds when they are shooting rifles off the side of the bed. The sight clears the bed, but the barrel doesn't.
Take 10 minutes and watch this. DJ explains it perfectly.

 

[erwos]

IMHO, the killer problem with the risers isn't HoB aiming offset (a thing that is pretty much always a consideration with rifles to a greater or lesser degree), it's barrier/port usage. You find out pretty fast that > 1.7" optics suck bad to use on VTAC-style barricades.

 

[Blaster229]

IMHO, the killer problem with the risers isn't HoB (a thing that is pretty much always a consideration with rifles to a greater or lesser degree), it's barrier/port usage. You find out pretty fast that > 1.7" optics suck bad to use on VTAC-style barricades.

What's a VTAC style barricade? How often are they encountered during CQB inside a dwelling?

 

[erwos]

What's a VTAC style barricade? How often are they encountered during CQB inside a dwelling?

https://www.vikingtactics.com/v/vspfiles/pdf/vtacBarricade.pdf

Commonly used in the training world for forcing people to shoot from unconventional positions and ports. May or may not have relevance inside a dwelling (although consider situations like partially opened doors!); more use for outside stuff.

ETA: AR15buildjunkie has an interview with Mark Smith on this topic that is absolutely exquisite and a must-read:

High Scope Mounts on the AR-15 – A Q&A with Mark Smith – AR-15...

If you are in the market for a new scope mount, you may have noticed the trend towards high scope mounts for red dot optics and LPVOs

www.arbuildjunkie.com

ETA #2: one more thought: I would agree that Hydra-style risers that are putting you at 2.96 or something similarly absurd are a really bad idea 99.99% of the time, but even the NV-shooting world would typically agree with that statement. 1.93-2.25 is where the trade-off might be worthwhile if you use night vision frequently.

 

[Blaster229]

https://www.vikingtactics.com/v/vspfiles/pdf/vtacBarricade.pdf

Commonly used in the training world for forcing people to shoot from unconventional positions and ports. May or may not have relevance inside a dwelling (although consider situations like partially opened doors!); more use for outside stuff.

ETA: AR15buildjunkie has an interview with Mark Smith on this topic that is absolutely exquisite and a must-read:

High Scope Mounts on the AR-15 – A Q&A with Mark Smith – AR-15...

If you are in the market for a new scope mount, you may have noticed the trend towards high scope mounts for red dot optics and LPVOs

www.arbuildjunkie.com

ETA #2: one more thought: I would agree that Hydra-style risers that are putting you at 2.96 or something similarly absurd are a really bad idea 99.99% of the time, but even the NV-shooting world would typically agree with that statement. 1.93-2.25 is where the trade-off might be worthwhile if you use night vision frequently.

Pretty sure not an issue for a pro in a CQB environment.

 

[erwos]

Pretty sure not an issue for a pro in a CQB environment.

Neither is knowing your offset. *shrugs*

Sent from my SM-G981U1 using Tapatalk

 

[Blaster229]

Neither is knowing your offset. *shrugs*

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At least you'll be able to negotiate a VTAC barricade when you encounter one in real life. Lol

Well hopefully someone will learn something from this video, because you sure don't need it.
Poo pooing on the Hydra when I didn't mention it is a strong flex.

 

[outrider58]

There are race guns and there are tactical guns(we'll stop there in this situation). Neither is the the best for the other use.

Plain and simple.

 

[erwos]

At least you'll be able to negotiate a VTAC barricade when you encounter one in real life. Lol

VTAC barricades, when used correctly, help promote good gun handling skills. I would also suggest that knowing how to shoot a rifle quickly and accurately from a small port is not a bad life skill in general.

Poo pooing on the Hydra when I didn't mention it is a strong flex.

You mentioned tall risers. Not much out there taller than a Hydra. I also brought up other riser heights popularized by Unity mounts.

There are race guns and there are tactical guns(we'll stop there in this situation). Neither is the the best for the other use.

Oh, absolutely agree. Been living that lately, in fact. But, in this situation, I don't think it's a competition vs tactical argument. No one's using tall risers for dedicated competition guns because multigun and PCC shooters want to minimize height over bore so they don't have to think about it as much on close-in targets. Most guys there are running 1/3 cowitness (1.7) at most.

The genuinely tall risers (1.93+) are designed for guys running night vision setups, which I would broadly define as a tactical thing. I am sure there are people out there running them for the cool-looking factor, but they don't really have much practical use in that regard. But short of a Hydra-style mount, you're talking like .5-.75 difference in HoB compared to a normal mount. It's just not that much on a head-sized target at 7-10yds. If you're shooting a two-credit-card size USPSA A-zone head, it's a bit more of a going concern... but no one's been attacked in real life by a USPSA target, right?

 

[outrider58]

Oh, absolutely agree. Been living that lately, in fact. But, in this situation, I don't think it's a competition vs tactical argument. No one's using tall risers for dedicated competition guns because multigun and PCC shooters want to minimize height over bore so they don't have to think about it as much on close-in targets. Most guys there are running 1/3 cowitness (1.7) at most.

The genuinely tall risers (1.93+) are designed for guys running night vision setups, which I would broadly define as a tactical thing. I am sure there are people out there running them for the cool-looking factor, but they don't really have much practical use in that regard. But short of a Hydra-style mount, you're talking like .5-.75 difference in HoB compared to a normal mount. It's just not that much on a head-sized target at 7-10yds. If you're shooting a two-credit-card size USPSA A-zone head, it's a bit more of a going concern... but no one's been attacked in real life by a USPSA target, right?

You kinda made it a tactical vs competition comparison when that was not the OP's position.

...and maybe not direct fire, but I did suffer a double perforation trying to clear a jammed staple gun on the pistol range once(always make sure your staple gun is cleared before clearing a jam).

 

[Blaster229]

Geezus fcking Christ.

Erwos=never used a weapon in real life
DJ Shipley and Mike Glover=relied on weapons for survival.

Erwos=throwing shade against guys because he watched videos.

What kind of bizzaro world is this?

 

[erwos]

You kinda made it a tactical vs competition comparison when that was not the OP's position.

No, I must certainly did not. You seem to be making the assumption that VTAC barricades are a competition thing, which they aren't. You know who came up with VTAC barricades and the nine hole drill? Kyle Lamb. See this article: https://www.gunsandammo.com/editorial/firearms-training-the-9-hole-barricade/307337

For everyone else's awareness, Kyle Lamb was on Delta. He's not a competition guy. I don't think I've ever seen a true VTAC barricade at a multigun match (but my memory may also be failing me on that one).

As for blaster's claims, I didn't throw shade on the video (which is a good video!), but I did say that I think aiming offset at 10yds and in isn't the biggest problem with high mounts, even if it remains a substantial problem. Still sticking by that one, and I don't think it contradicts the video.

 

[Qbeam]

So would a 25yd zero be less HOB than 100yd zero HOB? I would guess slightly, but as you get to 7-10 yds, you would eventually get to the 4-6 inch hold over. So at close range, aim for the base of the neck, hit the chest?

Q

 

[erwos]

So would a 25yd zero be less HOB than 100yd zero HOB? I would guess slightly, but as you get to 7-10 yds, you would eventually get to the 4-6 inch hold over. So at close range, aim for the base of the neck, hit the chest?

Q

This is a fantastic question. Maybe I'm misunderstanding this, but for a typical carbine zero at 25-50yds, your holdover would approach the actual height over bore as you got closer and closer to the target. Think about the Eotech reticle for a second - for a typical 5.56 carbine, the bottom of the circle is the hold for a 7yd shot when you're zeroed at 50yds. Visualize that - does that seem like 6"? I don't think so. What I see online seems to think it's closer to 2". I agree that you would need to hold slightly higher with a 100yd zero, but I doubt you'd make it all the way to 6 unless you had one heck of a riser.