As the regular dissenting voice, when it comes to carbine applications, I present another annoying idea. It's hard to argue with "decide what you want the rifle to do, and build it to best suit that task". Having a fleet of purpose-built weapons is great; choose the one that is catered to the task at hand, and you get maximum performance, in that use-case. But what if we don't have a video game weapon inventory in our prison wallet? What if we don't have the luxury of regular access to a secure weapon storage between our various "missions"? What if we're not picking the best tool for the best times on the square range punching paper?

When we consider the biggest equipment factors, that differentiate between performance objectives, so long as we're staying within the same caliber (in this case 5.56), I think we're considering barrel length and optics. The rifle optimized for CQB will have a shorter barrel and a forgiving non-magnified optic, like a red dot or holographic, or perhaps only irons. The rifle optimized for medium range would do well to have somewhere between 4x and 10x magnification potential, and likely a longer barrel, to maintain performance and less extreme trajectories at longer ranges. If both of these factors were married to the rifle, the way a barrel is, it'd be tough to have the same weapon perform across the whole medium range to CQB spectrum; but an optic is not so married. I'll also introduce a third performance scenario, to further illustrate potential advantages of optical versatility: the NVG carbine.

QD mounts from reputable manufacturers are repeatable; they can be removed and re-installed and return to zero. We can keep our magnification for it's advantages, in most applications, if we do indeed value the medium range and observation abilities it enables, and, with the throw of a few levers, switch to an optical setup that favors close range or NVG circumstances, if that is what we're faced with for the foreseeable future. An Eotech and a LPVO can both take up minimal space in a pack, or "go bag"; lasers can too. If a user so chooses, he can decide what's the longest barrel he feels comfortable with in close quarters, and then build his aiming systems on that foundation, to enable CQB and medium range use, day or night, with the same rifle.

What foundation configuration you choose, how you maintain your foundation, and how you scale the system is up to you. If I perceive the medium range setup to favor my most likely use-case, I'll leave the LPVO installed, and swap to the Eotech as needed; then I may opt to keep the laser mounted full-time, or make it a scaled item as well, to keep weight and bulk down in most circumstances. If CQB is your most-likely use case, keep that magnified optic stowed, and maybe the laser too; or not, if your mission has you in dark interiors or circumstances where even a visible laser may provide an advantage.

All food for thought. I believe the "general purpose"(don't hurt me) rifle is a reality, inside the parameters of a medium range maximum utilization.

*Magnifiers may be mentioned in comments. I am not crazy about magnifiers, which is why they aren't mentioned in this OP. They really are the blah "general purpose" attempt that everyone ought to dislike, IMO. If one decides a magnifier is the way to go, for them, I think a mount that facilitates their quick removal and re-installation is essential, in order to remove that bulk from the gun, when it's not needed.

**Excuse my pretentious use of the word paradigm; in my defense, it does suit the topic. Also, for the purpose of this discussion, I think "medium range" can be defined as no further than 400m.

You know what they say about opinions; Lord knows mine stink. Let the beating commence...

Bro

That’s a wall of text.

My apologies. I fixed it. I guess I was in the zone, getting the thoughts down.

Interesting exercise. Have you considered the potential to have several complete uppers that can be used for different applications? Personally I feel an 11.5” and 14.5” or 16” would give full spectrum 5.56 capabilities.

A less conventional option is a 16” barrel Steyr AUG with A3SF optic, piggyback red dot, suppressor gas valve, Corvus case deflector, Corvus MLOK front rail with laser and white light. I’m going through this exercise right now with one of my AUGs.

For me, a 12.5” carbine with lpvo, piggyback or offset red dot, laser, and white light is a near do-everything from 0-500 meters rifle.

My personal current do-all setup is:
-12.5” BRT CHF CL barrel
-Geissele mk16 10” rail
-NF 1-8 nx8, capped turrets, fcdmx reticle in 1.93 NF Ultramount
-DeadAir Sandman K
-Geissele SSA
-DesignateIR-V laser
-Arisaka white light
-Dual modbutton light to run above two items
-Working through offset vs piggback ACRO-P2

A separate 14.5” or 16” upper with a Leupold mk5 3.6-18 (or NF ATACR 4-16 or S&B 5-20 Ultrashort), piggback or offset red dot, laser, suppressor, etc would give capability at longer distances. I would give a nod to 14.5” simply because it stows easier.

Add in clip on thermal and dual tube nvg.

quote:

several complete uppers

If we consider more uppers, we're back to needing not insignificant storage/transport accommodations; a vehicular base at the very least. It seems, to me, that, if I am to have another upper, I may as well have another rifle. Multiple uppers maybe makes sense in the military context, so the soldier is still only issued "one rifle". Also, I'd likely omit the middle ground, and have one in a 10.5" and one in an 18".

I considered the bullpup approach last year; specifically an AUG with STANAG stock. I haven't fired a suppressed 5.56 AUG, but I have fired a suppressed 9mm AUG, and it was terrible; I can only assume a 5.56 bullpup will also be louder at the ear, due to the ejection port location. I am not willing to sacrifice the suppressed functionality of the DI AR.

If you were to have a companion upper, for your 12.5", I'd certainly go for the 16", or even an 18". I don't see the minor addition of 2"-worth of capability being worth the entire separate rig.

*What's the accuracy like, with good ammo, out of that BRT barrel?

quote:

Interesting exercise

It is, and it isn't (an exercise). I say that because I have been doing it this way for almost two years now. When I started to really prioritize passive NV aiming, I realized the Eotech is the best equipment for that; and, for me, it's an Eotech on a riser. First, that meant a "night gun" (or "night upper"), but I quickly realized that's a recreational and/or direct-action with infrastructure concept; it doesn't really work for a "prepared citizen", the way that I understand that term. I don't know what inspired me to play the optic switching game, but it's viability became immediately apparent; I've been doing it since, and that's what I'll do moving forward. Just keep your alternative aiming setup packed with your NVG; when it's time to don the NVG, it's time to swap the optics; it's too easy.

*I am curious as to your feedback on the NV equipment you employ. If you're so inclined, maybe share your thoughts in the NV/thermal thread. I am specifically interested in your experience with the DesignateIR-V, dual modbutton, and ACRO. I use PEQ or OTAL lasers, SF Vampires, Unity or OEM switches, and the aforementioned Eotech. It seems, based on my liking of a riser for passive aiming, that piggyback would be the way to go, lest you have quite the stem on your offset mount. But, when piggybacked, do you run into clearance issues with the primary optic and the NVG?

From doing a lot of CQT, I can tell you that the best “do all” option is an ATACR or Razor with an offset RDS of some type. But, even at that, it’s a trade off. That set up will never be as good as primary RDS for CQT, or 1x10 for intermediate uses. A major trade off. As a stand alone Unsupressed weapon system, there is no direct trade off between CQT combat with a 11.5, 12.5, or 14.5 inch barrel AR. If there was a great difference, we would be running 10.3 guns unsuppressed because of the perceived advantage. We would be accepting the advanced wear and tear on hard use SBRs. But, there isn’t. It isn’t until you hang a can on it that we start considering length, and we drive the overall length up to 16 or so inches with the can.

So now that we address that from a fundamental standpoint, the trade off becomes mission oriented. swapping optics “sorta” could be a work around. However, I don’t know a single professional that would remove a LVPO and trust the return to zero capability on a RDS to do hostage rescue with. That’s why most hostage rescue units still run some form of red dot sight as opposed to running a Razor/RDS combo. But, we’re talking about efficiency of the trade, not “can it be done”.

If we are truly trying to milk a Jack of all trades, the answer is a 14.5 inch URG-I type upper, ATACR in a 1.93ish mount, offset RDS (you pick it based upon your needs or NVG compatibility), short can like a Surefire mini, or Sandman-K, and a PEQ of your choosing if you have NODS.

In my opinion, swapping optics is a no go from a liability standpoint alone. Even if you are talking some end of the world stuff, you might have to conduct some type of HR with loved ones involved. You have to ask, do you trust their lives to “return to zero” no matter how good it is?

As much as the OP doesn’t like the magnifier route, it would be the direction I would go to do it all. Especially adding in a choice of one of the Eotechs with built in hold overs. I view “missions set” in the context of what I perceive the OP to mean (more Ukraine than Baltimore), if I miss a shot at a guy with a magnifier at 400 yards, I’ll just come back and try it again in a week. I won’t get a do over on HR. So, that would be how I would prioritize.

I always appreciate your contributions, jljones.

I suppose I should have mentioned in the OP, that I consider a silencer mandatory equipment. It doesn't necessarily have implications in the more general discussion of the concept presented, but it certainly drives my gravitation toward a barrel shorter than what many might consider practical for "medium range". The weapon's handling is important on both fronts of the GP's application: CQB and patrolling; one has you navigating tight spaces, and the other has you toting the weapon for extended periods. A silencer turns a 10.5" barrel into a 16" in an instant.

I can only report what I have seen, with the equipment I use. My ADM Recon mount, which holds my LVPO, has been on, off, rode around in a backpack, on again, and printed a tidy group at 500m. I haven't proven my Eotech on a Larue to that degree (I ought to), but it hasn't given me noticeable trouble so far. If hostage rescue was a big chunk of my use-case, it's likely CQB is a majority of my use-case, and we're no longer within the borders of the GP discussion. Of course any mount ought to be proven, and proven repeatable, time and time again, by it's user, before it is to be counted on in such a high stakes scenario as hostage rescue. Given my experience with the ADM, I'd say it's possible, but, as you say, not efficient for such a specialty circumstance.

I haven't been convinced of the offset RDS yet. Considering my confidence in the RTZ of my setups, and my wanting to maximize NV functionality, I think switching is the way to go. Is the LVPO useless at night? No; but it's mostly useless. I feel like I am short-changing myself, relying on a MRDS in the dark; I wouldn't choose one as my primary optic during the day, why would I choose it at night? But, like I said, I am not convinced, and therefore haven't invested in a MRDS, and therefore haven't tried it. I likely will, at some point or other; my opinion may change.

quote:

do you trust their lives to “return to zero” no matter how good it is?

That may qualify as hair-splitting. Do we trust their lives to optics that rely 100% on batteries to provide a reticle? Do we trust their lives to an open emitter? I took note of your comment in the 933 thread, concerning fixed front sights. I don't have a big feeling either way on them, but I do prefer a folder with an LVPO, as the 1x fish eye effect can put stuff on your top rail in the FOV in a big way. It's six in one and a half-dozen in the other though, as a failed battery wouldn't result in an absent reticle, in the case of an LVPO.

My experience with magnifiers is limited, because I didn't really care for it. I find the FOV to be lacking, and there's more surfaces to keep clean.

quote:

I won’t get a do over on HR. So, that would be how I would prioritize.

As you should.

Thank you for the valuable, experience-driven feedback, jones.

quote:

Originally posted by KSGM:

quote:

several complete uppers

If we consider more uppers, we're back to needing not insignificant storage/transport accommodations; a vehicular base at the very least. It seems, to me, that, if I am to have another upper, I may as well have another rifle. Multiple uppers maybe makes sense in the military context, so the soldier is still only issued "one rifle". Also, I'd likely omit the middle ground, and have one in a 10.5" and one in an 18".

I considered the bullpup approach last year; specifically an AUG with STANAG stock. I haven't fired a suppressed 5.56 AUG, but I have fired a suppressed 9mm AUG, and it was terrible; I can only assume a 5.56 bullpup will also be louder at the ear, due to the ejection port location. I am not willing to sacrifice the suppressed functionality of the DI AR.

If you were to have a companion upper, for your 12.5", I'd certainly go for the 16", or even an 18". I don't see the minor addition of 2"-worth of capability being worth the entire separate rig.

*What's the accuracy like, with good ammo, out of that BRT barrel?

quote:

Interesting exercise

It is, and it isn't (an exercise). I say that because I have been doing it this way for almost two years now. When I started to really prioritize passive NV aiming, I realized the Eotech is the best equipment for that; and, for me, it's an Eotech on a riser. First, that meant a "night gun" (or "night upper"), but I quickly realized that's a recreational and/or direct-action with infrastructure concept; it doesn't really work for a "prepared citizen", the way that I understand that term. I don't know what inspired me to play the optic switching game, but it's viability became immediately apparent; I've been doing it since, and that's what I'll do moving forward. Just keep your alternative aiming setup packed with your NVG; when it's time to don the NVG, it's time to swap the optics; it's too easy.

*I am curious as to your feedback on the NV equipment you employ. If you're so inclined, maybe share your thoughts in the NV/thermal thread. I am specifically interested in your experience with the DesignateIR-V, dual modbutton, and ACRO. I use PEQ or OTAL lasers, SF Vampires, Unity or OEM switches, and the aforementioned Eotech. It seems, based on my liking of a riser for passive aiming, that piggyback would be the way to go, lest you have quite the stem on your offset mount. But, when piggybacked, do you run into clearance issues with the primary optic and the NVG?

I think having two uppers would not be bad. Could easily keep in a backpack with other accessories, batteries, etc. I would not trust the return to zero on a QD optic. I’d go 11.5 and 14.5 or 12.5 and 16.

AUG with suppressor gas valve and a low back pressure can suppresses fine. Not as good as an AR of course. But good enough.

Molon got just over 1” with a BRT CHF CL barrel. I’ve not shot mine for groups, only shot steel from
100 - 500 yards so far.

I’m a neophyte re: nvg and thermal. I have a set of L3 1531, a DesignateIR-V, MAWL-C, and Arisaka white lights. Currently I don’t have a piggyback red dot, but I’m planning to add an ACRO-P2 to my nx8. I have a T1 in an Arisaka offset mount and I want to compare the two. Arisaka makes a 1.93 offset mount too, which can be used with nods.

Many of my friends are really deep down the nvg and thermal rabbit hole, so I have the benefit of seeing their setups evolve.

quote:

QD mounts from reputable manufacturers are repeatable; they can be removed and re-installed and return to zero.

No one I’ve ever met trusts QD mounts to be accurate if removed and reinstalled.

Pro shooters have a period for sighters before a new match-because people may have bumped their scopes.

Professional hunters always check their zero by firing live rounds.

My local gunsmith builds rifles and uses the same pic rail on every rifle, and bounces his scope from rifle to rifle when he test fires a rifle for a customer-and when he puts it back on his rifle he zeros it.

I carried an AR as a cop and I was restricted by policy to use only irons…(and that’s because they knew not all officers would shoot their gun often to confirm zero) so only the SWAT guys got to use optics-but they also used pelican cases

The QD mount is apparently an interesting phenomenon. Seemingly no one trusts them. How is there such a healthy portion of the industry dedicated to them? I am not going to bat for them; I understand where y'all are coming from; I have used them with success though. Considering I appear to be a minority, why has QD taken such a hold?

Another interesting series of questions.

My preference is to have different weapons for different purposes. Military sniper teams often consist of a man with a precision rifle, but the other members are armed with the organization’s battle rifle. It’s not even unknown for military snipers to carry both types of rifles at the same time when moving to the firing position. But of course having multiple weapons may not desirable or even feasible for the civilian.

As for the popularity of quick detach mounts, I have them on my Aimpoints with rifles intended for close range use, but that’s primarily because they make removing and attaching easier when necessary; I don’t swap sights willy-nilly, and I check zeroes after they are removed. Plus, I’ve never formally researched the question, so I can therefore only guess about some of this, but I do have some thoughts.

My first is that people who use QD mounts without going to the trouble of confirming zero after every swap are not all that concerned about accuracy. I recall one advertisement for a mount that claimed the shift after dismounting and mounting was no more than 1 minute of angle. Well, if our idea of precise accuracy is hitting a 12 inch target at 300 yards with bulk M193 ammunition and shooting offhand or even over a rolled-up coat on a rickety bench, then a 1 MOA shift is probably of no concern whatsoever.

The same is probably true of the deer hunter shooting from field positions with a rifle and ammunition combination capable of 2.5 MOA groups on a good day. As for hostage rescue in a commercial building, 15-20 yards would be a long shot, and at the maximum, 1 MOA would shift the point of impact by about 0.2 inch; it would be an exceptionally skilled LEO who could keep his shots within that measure while getting off a 2.5 second standing unsupported shot after rolling into the room and assessing the situation.

Even a POI shift of significantly more than 1 MOA would not be of much, if any, concern to most shooters in most applications, and I’m guessing that most shooters aren’t skilled enough or shoot under demanding enough conditions to even notice such shifts.

But not everyone is a “most” shooter. If we’re trying to hit a 10" plate at 1000 yards, then even something as small as a 1 MOA shift would not be acceptable. Although it would be unusual for a law enforcement sniper to need to hit the half of a hostage-taker’s head that he can see at 150 yards, if that were what he was faced with, he wouldn’t want the bullet to hit an inch and a half in some unknown direction from where he was aiming (on top of the normal dispersion of his weapon system).

As I say, though, it’s another interesting question to ponder.

I recently went looking for a lightweight, compact, 6 to 10x fixed power scope that could be paired with an ACRO. Sadly my results came up lacking.

Seems my accuracy/velocity testing with the incoming Noveske barrel is now going to include QD on/off testing as well.

Good point on the minimal shift at close range, sigfreund. Though the stakes are high in a room-clearing hostage rescue situation, the ranges are such that it's a non-issue, if we are indeed talking 1MOA.

The LE sniper shooting for the half-head at 150M isn't the dude who's switching optics anyway. Nor is the 10" plate at 1000Y dude.

quote:

Originally posted by KSGM:
Do we trust their lives to optics that rely 100% on batteries to provide a reticle? Do we trust their lives to an open emitter? I took note of your comment in the 933 thread, concerning fixed front sights.

Well, actually we do.

All of the perceived pitfalls of what I consider to be a nameless, faceless boogeyman (open emitter) can be simply disregarded with adopting a closed emitter system like an ACRO. Potential problems with battery powered optics can be easily managed. Do battery powered optics go down at the worst of times? Of course they can, and having a back up plan and training that plan is important. But on the scale of problems, proper selection of equipment and a routine care of such equipment makes the concern the exception and not the rule.

We tend to slap a red dot sight on a pistol or rifle and then adopt a mindset that it’s a sniper rifle. Zeros do shift however slightly almost daily with changes in weather. But the shift is generally only noticeable when the gun is bagged and shot from a very stable platform. Most shooters, to include me, can’t tell a practical difference in the shift shooting free style. I’ve spent most of this year so far studying this, if nothing but out of curiously. There is a slight shift in zero between our duty ammo and XM193. It’s about an average of 2/3 MOA at 50 yards. Most shooters won’t notice it really. Which is why I don’t preach trying to precisely dial in the zero on range days with training ammo. Your zero should give you the majority of the rounds fired in a two inch circle at 50. That’s with the gun being fired from a rock steady position with duty ammo. The combination of eyesight, the gun and ammo becomes the enemy of the good at chasing a precise zero with a RDS. Especially when you’re only talking plus/minus 1/4-1/2 inch at 50. Some dudes can do it. I can’t.

With swapping optics on the fly, you introduce a variable that you can’t accurately to into account for the performance that you potentially lose. Sometimes the results are great. Sometimes not. I’ve been swapping optics on the gun I have been shooting quite a bit, and it has never given me a result that I am comfortable with saying “when you apply X, you get Y”. It’s like keeping a bad magazine in rotation to me. It’s just not worth the potential problems it may cause.

As to the FSP guns, I think it’s a romance thing to me. I spent as much of my career with a MP5 that I have with a carbine. When we made the jump, it was the era of the Block 1.5 and Block 2 guns. We didn’t have near the financial support that we enjoy today. We had Rock River, Smith and Wesson, Colt carbines and not HK416Ds. They only came along in the last 10 years or so. I spent a lot of time shooting a Block 1.5, and later I added an Ergo rail to give it that Block 2 feel. I originally had one of the Trijicon Reflex sights, and thought I was somebody when I got an Aimpoint. That romance of days gone by still holds a place in my heart. I give my guys all the new stuff as it comes in. If for whatever reason I had to go back to a FSP gun, I’d do so with a smile.

Another interesting option is something I have been watching from Lucas Botkin. He’s put out quite a bit on content with a ACOG TA02 with a MRDS mounted in the forward position. This allows some distance with the ACOG, while the forward mounted MRDS is still NOD friendly.

quote:

I’ve been swapping optics on the gun I have been shooting quite a bit, and it has never given me a result that I am comfortable with saying “when you apply X, you get Y”.

What kinds of shifts did you see? Did you go off and on again with the same optic/mount? What mounts are you using?

One thing I wonder about the piggybacked MRDS (ACOG or otherwise) is clearance around the NVG housing. It seems to me that your NVG housing would be consistently bumping into the top of the primary optic.

Of course I am aware of closed emitter MRDS options, and I am versed in battery management. I was merely proposing that a potential ~1MOA shift, in the context of CQB, or even medium range engagements, is no more of a concern than those two boogeymen. As sigfreund suggested, we're talking about a shift no greater than the diameter of the bullet, inside 20 yards.

I hope you can provide further insight into the optic swapping consequences you've experienced, with your equipment.

quote:

Originally posted by KSGM:
The QD mount is apparently an interesting phenomenon. Seemingly no one trusts them. How is there such a healthy portion of the industry dedicated to them? I am not going to bat for them; I understand where y'all are coming from; I have used them with success though. Considering I appear to be a minority, why has QD taken such a hold?

I think QD optic mounts had a hold for a time when they were novel in the early 2000s. At present, they are less the paradigm and more the holders on. Magnifiers, clip on i2, and clip on thermal are about the only applications for QD optic mounts IMO.

quote:

At present, they are less the paradigm and more the holders on

It seems I typically exist about five to ten years behind the curve, when it comes to gear and techniques, so that makes sense.

I am still curious about those with NV, who use the piggyback MRDS. Assuming you have also used something like an Eotech or Aimpoint Micro in a high mount, do you perceive any real compromises in using the piggyback setup? Any clearance issues between the NVG and primary optic when bringing the weapon to bear?

I am no expert and do not claim to be anywhere as qualified to weigh in as other folks here. I have tried LPVO and fixed prism setups over the years and have some observations.

My favorite setup is a 3.5 ACOG like a TA-11. The field of view and eyebox is forgiving compared with 4x ACOGs and the reticle can be used both eyes open up close. After zeroing, I got onto steel at 700 yards with surplus 147gr ball ammo using a Scar 17s with zero issue or fuss. It just worked.

I also like using an Aimpoint PRO and a T2 for closer stuff. I have 100% confidence that they'll work every time I turn them on.

quote:

Originally posted by JoshNC:

quote:

Originally posted by KSGM:
The QD mount is apparently an interesting phenomenon. Seemingly no one trusts them. How is there such a healthy portion of the industry dedicated to them? I am not going to bat for them; I understand where y'all are coming from; I have used them with success though. Considering I appear to be a minority, why has QD taken such a hold?

I think QD optic mounts had a hold for a time when they were novel in the early 2000s. At present, they are less the paradigm and more the holders on. Magnifiers, clip on i2, and clip on thermal are about the only applications for QD optic mounts IMO.

I have an AR that pulls double duty with a LPVO in a Larue QD mount and a thermal in an ADM mount. While I wouldn't trust the rifle to go to a match out to 4 or 500 yards at a match without confirming zero. It does return close enough for out to 100 or 200 yards every time. That's my backup rifle for matches so I haven't taken the time to do a repeatability test on the return to zero aspect of the mounts. I have dismounted the thermal a couple times and it has returned to zero well enough to hit coyotes at 400 yards. I don't really consider that to be a precision AR so I haven't checked it at a finer accuracy level than minute of coyote.

Minute of coyote at 400 is pretty good. I am gonna put my two QD setups on paper, here in the next week or so. I have done it before, but never back-to-back, for record. We'll see how it looks. I'm going to use M193 at 100M. I'll consider trying 77gr OTM at 300M, if the results at 100M somehow prompt further testing.