DarkLordOfOptics
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Guns, Optics, 2nd Amendment and resisting the Left in everything they touch.
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MPVO vs Crossover

These two terms get thrown around a lot, by me most of all, while what they really mean is very much open to interpretation. I do not have the power to unilaterally define them. I can, however, at least explain what I mean when I use them.

The term crossover scope arguably came about due to the advent of western hunting. Out west, it is not uncommon to take a shot on game from a considerable distance often in pretty gnarly conditions. That requires something akin to a precision scope if you want to do it well. Modern precision oriented riflescopes are frequently large and heavy. While it is possible to drag one uphill with you, it is not something I recommend. Plenty of people do it and I applaud their mental fortitude. I've done it and I don't like it. It is hard enough to drag my fat ass uphill. I am clearly not the only one, since quite a few years ago Premier Reticles came out with their Light Hunter scope. That was a version of their 3-15x50 design, except with simpler and lighter turrets all stuffed into a 30mm tube. Optically, it was the same as the larger tubed scope, but it weighed a lot less. It gave up some adjustment range and turret features, but that's largely it. When Premier went under Armament ended up with their assets. The scopes were re-engineered and improved. Then re-designed again and merged with a different ongoing development project that resulted in Tangent Theta scopes. TT315M and TT315H are the spiritual successors to the Premier Light Hunter: 3-15x50 scopes with 30mm tubes, limited adjustment range, simpler turrets and spectacular optical performance. They weigh around 27 ounces.
In parallel, Bushnell made their 3-12x44 and 4.5-18x44 LRHT scopes for a while (eventually they Bushnell-ed them), Leupold developed the 3.6-18x44 Mark 5HD and, more recently, Vortex introduced a 4.5-22x50 Razor HD-LHT. The latter, along with the Tangent are probably the purest expressions of the crossover concept we have today.
What's a crossover scope, then? To me, it is a FFP scope with max magnification of no less than 15x, illuminated mrad (or MOA for the masochists among us) reticle, elevation turret equipped with a zero stop and locking or covered windage turret. The objective lens diameter should be between 40 and 50mm. The scope weight should be no more than 30 ounces. Many of these criteria are somewhat arbitrary, but I have to draw the lines somewhere. On the low end I am looking for magnification of not more than 5x for an occasional offhand or badly supported shot. It is important that the reticle works adequately well across the entire magnification range, which is one of the reasons I require illumination. That is also why, to me, tree or grid type reticles that illuminate the whole thing are a problem. I want a small center portion of the reticle illuminated: a dot or a crosshair. You can get clever with it and illuminate a few more hold points, but not the whole thing. That has a tendency to make the scope useless in low light.

MPVO stands for Medium Power Variable Optic and the concept originated when people started thinking "what if I wanted to make an LPVO like scope, but did not need 1x on the low end?" 1x definitely complicates everything and one thing we can do by getting rid of it is bump up the objective diameter a little and optimize optics better for mid-range magnification. Original MPVO concept was sort of like a "tactical tweener". The purest expression of that original idea is Leupold Mark 5 2-10x30, Vortex PST Gen2 2-10x32 also sorta barks up the same tree, but it really did not set the world on fire. The Mark 5HD is an interesting design that I plan to test in the not too distant future. Given the absolute reluctance of most manufacturers to make high quality FFP riflescopes with objective lens diameters between 30 and 40mm, the definition of an MPVO got extended to include larger designs with 40-ish millimeter objectives. For these, the definition is a little different in that one of the binding criteria is low magnification, with higher magnification being a lot more flexible. To me, one of the absolutely critical requirements of an MPVO is reasonable compatibility with commercially available thermal clip-ons. That means the low end FOV had to be at least 7.5 degrees or thereabouts. That translates to around 40ft @ 100 yards. Wider is even better (closer to 50), but 40 is reasonable. For most riflescopes, that's between 2.5x and 3x. For some short-ish eyerelief prismatics, you can get close to that FOV on 4x, but they are not variable optics.
The rest of the specs are simple: FFP reticle with some ability to hold over, locking or covered elevation turret preferably with zero stop (but reticle only distance and wind holds are acceptable, so no zerostop is OK), covered or locking windage turret, objective lens diameter between 30 and 44mm, weight of less than 30ounces. Lighter is naturally better.
There is some obvious overlap between MPVO and crossover optics, but I prioritize different features with these two scope types.
Here are the two configurations I would consider ideal that, hopefully, illustrate my point.

Ideal crossover:
30mm tube, illuminated tree reticle (Vortex XLR2 or similar), 3.4-17x50, side focus, 20 ounce weight, 3 - 3.5" eye relief, single turn 12mrad turret with 0.1mrad clicks, no low power tunneling, covered low profile windage turret, exposed low profile zerostop elevation turret. Essentially, I am looking for a fusion of Razor HD-LHT and USO FDN-17x.

Ideal MPVO:
30mm tube, illuminated abbreviated tree reticle (S&B's MDR-T6 or similar), 2.4-12x36, side focus, 20 ounce weight, 2.5 - 3" eyerelief, single or double turn turret with 0.1mrad clicks and at least 10mrad of available adjustment, locking zerostop elevation turret, covered low profile windage turret. Essentially, I am looking for a fusion of the Mark5 with Blackhound Emerge or something in between. Leupold turrets are near perfect for this application.

Neither configuration currently exists. Both are eminently makeable and whichever OEM currently makes the Razor HD-LHT 4.5-22x50 with sub 22 ounce weight, can pull off these exact configurations if properly motivated.

Unfortunately, there is no one out there except for me who thinks these will sell. The wait continues....

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Nuclear Bright FFP LPVOs

This is a re-upload, so if you receive two notifications, my apologies.
The original upload got stuck on processing the video.

This originally started as a review of the Vortex AMG 1-10x24, but ended up being more of a direct comparison of what you get with these three modern LPVOs that have nuclear bright reticle illumination:

Vortex AMG 1-10x24 https://eurooptic.sjv.io/rEQm1y
Primary Arms PLxC 1-8x24 https://alnk.to/9xnqt1y
Vortex Razor Gen3 1-10x24 https://eurooptic.sjv.io/rEQm1y black anodize or https://alnk.to/4XzIXQ9 for bronze anodize

The first question will always be why I selected these specific three scopes. The obvious answer is simply because I had them. I was really hoping to get the new SAI10 here since it goes head to head against these group, but that was delayed. I will do an update when it gets here.

Why did I not include the two Nightforce options: NX8 and ATACR? Several reasons. Mostly because they have been around for a while and are a known quantity. I have looked at both...

00:28:27
Flashlights: Olight Odin Mini and PL X

Late last year Olight reached out to me and asked me if I want to review a couple of flashlights. I had never spent any time with any Olight products, so I took a quick look at the available specs and decided to give it a shot.
I suspect that Olight is quite irritated with me since, apparently, the stipulate a specific timeline to reviewers when they send them products. I was blissfully unaware of that (maybe I should have read the fine print) and did my usual thing where I spend an ungodly amount of time with whatever I happened to be reviewing before I run my mouth.

This video is long. I have hundred of rifle rounds and well over a thousand of handgun rounds behind each light. They shook a little loose, but not too much.

Beam evaluation you see in this video was done after lots of shooting.

Beam quality is quite good, but these are relatively budget lights, so I was pleasantly surprised. Build quality is also quite respectable

https://amzn.to/4x7Wpnt
https://amzn.to/3REL51O...

00:53:50
Long overdue: Element Theos 2-10x42

The amount of time I spent on this scope trying to find something really significant to nitpick on is borderline embarrassing. Yet, other than the original observations on it being a little heavy and that the reticle could have benefited from a couple more numbers, I really did not come up with much of anything.

It is decidedly a precision-oriented MPVO, yet it does everything well. In terms of pure optimization and understanding the real purpose of what these scopes are used for, the baby Theos is just superb.

While the current iteration of the excellent Primary Arms 1.5-12x36 PLxC is aimed at AR guys stepping up, the Theos is set up just right for precision guys trying to equip their accurate semi-auto with something a little smaller and lower magnification.

It is an absolutely exemplary design for stretching the range of an accurate DMR.

At the time when this is written EO has one for $2049, https://eurooptic.sjv.io/enEP06 which is an exceptional price for this scope. I thought it was...

00:22:35
Happy 4th of July, Y'all!

Having just spent ten days in Texas, I figured that I should throw a "Y'all" at you. It does not work all that great with my accent, but should be OK in written form.

USA is 250 years old today.

On one hand, it is not a lot for many national identities in this world (notice I said "national identities", rather than "nations" ).

On the other hand, we are the longest existing continuous republic that matters.

Technically, San Marino is the oldest sovereign republic that has been around for over 1700 years, but it is not exactly the most consequential entity out there. Even the eight people who know where to find it on the map without asking google, do not care about it.

America is more than a place on a map. America is an idea. Unlike most countries, which are defined by blood, soil, ancient tribes, or ethnic heritage (in case you are wondering, yes I am taking a shot at our esteemed VP Vance here who does not seem to understand that America is not just like other nations; it is unique), ...

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4th of July Sales are upon us

It seems like the industry is in a perpetual state of "let's discount something".
From a consumer standpoint, that's really not a bad thing.

Primary Arms is already on Day 3 of their Independence Day sale https://alnk.to/2FG2uls
That has several interesting things, on there. PLxC 1-8x24 SFP is still 50% off. I am surprised they still have any in stock: https://alnk.to/1N6fAhJ

Very unusually, there is a $450 off sale on a Q Sugar Weasel upper: https://alnk.to/6bZc6Hb

Reptilia mounts are about 20% off https://alnk.to/8ENNQ8S

Virtually everything from PA's optics line is either discounted or has a significant number of Bonus Bucks attached to it: https://alnk.to/3cqjqSu

Telson is not yet running anything that I can see, but there is always my dlo15 discount code for 15% off https://telsonoptics.com/shop/toxin-3-18x50-ir-ffp/?ref=llkqsdus

Tract has a free 250 years of Freedom t-shirt with any order that is more than $250. The more time I spend with their 10x42 LRF binocular, the more ...

RIP David Tubb

It appears that David Tubb, one of the true shooting legends we had, passed away yesterday. I heard he was hospitalized for a sever infection of some sort, but I do not have any significant insight into the cause of death.

David was 71. He will be missed.

David was always, somehow, a little bit ahead of the curve when it comes to shooting, whether gear or methods.

I met him at SHOT some years ago and chatted with him occasionally. He was incredibly generous with his knowledge and his time.

He joined me for a livestream a few years ago to discuss his reticle system.

Sadly, I never took him up on an offer to come shoot at his place. Something always got in the way.

May he Rest In Peace.

Spartan's CP Brace: Initial Impressions
In pursuit of stability

It has been a little time since I talked about Spartan Precision bipods and tripods.  That is largely due to my preoccupation with precision shooting during the last year and a half or so. 

I have two pieces of gear from Spartan: Ascent tripod https://alnk.to/28VEg3S and Javelin bipod https://alnk.to/gVPiEBd Both are very well made and rather quick to deploy, but they are not quite stable enough for the competition oriented endeavors I have been focusing on.  

For competition, it has been predominantly large diameter inverted leg tripods, like Zeiss' Max Duty kit and Triple Pull Ckyepod.  Inverted leg tripods are measurably faster to deploy and adjust when on the clock.  Triple Pull Ckyepod gives me the flexibility to shoot prone, sitting or kneeling in a pinch.

For hunting, however, I have been using the Spartan gear I listed above because it is light, easy to pack, fast to deploy and exceedingly well made.  It also really helps that the legs of the Ascent tripod come off for easier packing and for use as hiking sticks (that is highly useful when packing meat out and I like the idea of not needing to carry around separate walking sticks.

Most of my hunting rifles that I am not willing to attach a bipod to on a mostly permanent basis are set up for Spartan's Magnaswitch adapter.   It is slick, unobtrusive and can be used to snap either a bipod or tripod in.  It is not quite as stable at distance as a proper large diameter match tripod, but it is very fast to deploy and stable enough for my hunting purposes.

In the last few years, tripods have become an indespensible tool precision shooting when terrain is not conducive to shooting prone.  We use tripods for observation and target ID with binoculars and then immediately switch to using them for shooting support.  That is where things start to diverge a bit.

Some people clip the rifle into the Arca head of the tripod (that's what I have been doing lately).

Some keep a tripod table clipped in and do both glassing and shooting off of a bag sitting on top of the tripod table (that's what I started out with originally, but managing extra gear took too long.  I am more efficient now, so it might be time to re-visit this).

Some of the top competitors use two tripods for front and rear support (that's more gear manipulation than I am comfortable with).

When there is a front support, whether a tall bipod or a prop of some sort or just a convenient terrain feature, tripods are routinely used as a rear support to stabilize the butstock of the rifle.  That is what's commonly referred to as "tripod rear".

I have been trying to keep things simple and mostly just shot with the rifle clipped into the tripod.  I got quite competent at it when shooting at the range, but it has been a bit of a struggle in the last two matches (I also had some health issue in parallel, but I suspect that it had more to do with me screwing things up under time pressure than health concerns).

Still, while I continue to practice shooting with the rifle clipped into the tripod, both standing and kneeling, it was time to expand my horizons and try to master various variants of "tripod rear" support.

That is when I stumbled onto Spartan's CP Brace that offers a completely different approach to using a tripod for two point rifle support.

 It is a very clever idea.  They are, essentially, creating a bridge betweeh two legs of the tripod that has a compact tripod head attached to it.  That is the front support.  The rear support is the tripod's third leg where, similarly to the conventional "tripod rear" setup, you use your support hand to anchor the buttstock of the rifle to the leg of the tripod.

Like everythign Spartan makes, CP Brace is not cheap, so I figured I should take one for the team, do some experimentation and let you know what I find.

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Will HICAR and 6.5CM+Peak kill the M7 and 6.8x51?
One part of my hopes that it will. On the other hand, I hope that it will not.


Either way, it is going to continue to be a mess.

Last month, powers that be issued a solicitation for the HICAR program:
https://sam.gov/workspace/contract/opp/b1a57529aa574e8ba220e0311434733e/view

HICAR stands for "Hypervelocity Improved Capability Assault Rifle"

The solicitation is specific to SOCOM, rather than the larger branches of the military.  However, I strongly suspect that it is a harbinger of smarter things to come than the general issue of anything chambered for the 6.8x51 (aka as 277 Fury in the civilian world).

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Visiting with TacomHQ

This week was my kids' spring break, so we ended up going on a road trip of sorts.  We flew to Houston, rented a car, visited the Space Center, checked out Galveston, then drove up to Dallas.  My dayjob is in Dallas and I need to visit the office occasionally.  Truthfully, I need to visit the office more often than I currently do, but given my family situation that is a little tricky.

My kids are very good travel companions, so we decided to drive back to Albuquerque instead of flying.  The way the timing worked out, we had a day to make a detour and drive up to Arkansas to visit John Baker and his Tacom HQ operation.

I've known John for a few years.  He has visited with me about three years ago to talk about his their reticle idea and a few other things  

I think the reticle idea is sound and we should see a version of it in a scope soon enough.  I'll do a thorough coverage at that point.

This time around, the reticle was not the main reason behind my visit.  John is a creative guy and they do several interesting things there.  Everything they do is clever and outside the box.  For example, to the best of my knowledge, they were the first to come up with different ways to shift the POI for ELR shooting with their TARAC devices.  Alpha and Bravo TARAC devices use prisms to shift the zero of the optic, but a predetermined angle.  I have a flip-up Alpha TARAC set up to help with my subsonic ELR pursuits.  Bravo TARAC attaches the prism to the objective of the riflescope which works beter with large objective designs.  Since Tacom came up with it, the idea has been pirated by a couple of people, most prominently by Nightforce.  Technically, Tacom has a patent on it, but this appears to be a situation where a large company (Nightforce) shamelessly muscled a small company (TacomHQ) out of their IP, knowing fully well that they have more money for lawyers.  To be fair, John does not talk about it too much, so this is just a guess on my part (although I am sure I am going to get a nastygram from Nightforce lawyers for posting this.  They seem to really enjoy pushing small independent guys around).

Charlie Tarac uses a periscope instead of a prism to optically add slope for ELR shooting.  Delta Tarac does mostly the same things except it also offsets the line of sight laterally to avoid the mirage from the barrel.

The new thing with TARAC devices for this year seems to be an adjustable version of the Charlie.  There is a large side wheel that allows you to dial up to 900MOA of extra slope.

The reason I wanted to spend a little time with Tacom was the structured barrel.  I first ran into this concept a few years ago and thought it was an interesting idea.

Initially, my plan was to pick an appropriate action and have John make me a 300NM structured barrel for an ELR bolt action rifle.  I still want a 300NM and I might put one together eventually.  However, I never quite pulled the trigger on that for a few reasons.  One is that I simply have very limited use for such a gun.  I still want one, but I do not have easy access to a place wehre I can really stretch the legs of a caliber with that kind of capability.  The reason I wanted to put one together with a structured barrel is that they are are getting very good lifetime out of these and they are very easy to get to shoot properly.  

They have several version of the structured barrel design, but fundamentally they start with a 1.5" diameter barrel blank and mill out a bunch of material.  The most disinctive features are deep longitudinal cylindrical channels drilled parallel to the bore.  The start at the muzzle and go back toward the chamber.  They do not make it all the way to the chamber.  On the outer surface of the barrel, there are additional featuers designed for eliminating vibrational nodes and increasing surface area for better heat exchange.  There is quite a lot of technical informaiton on their website: https://tacomhq.com/structured-barrels/

Structured barrels look very beefy because they start out from large diameter blanks and they are decidedly not light-weight barrels.  However, by the standards of typical match barrels they are on the lighter side of things because of how much material has been removed.  Given their impressive vibration dampening advantages, a few months ago I shifted gears and started leaning toward putting together a large frame AR around Tacom's structured barrel.

With the precisely calculated mechancial structure, these barrels acomplish two very complicated things simultaneously: they are harmonically dead and they do not get hot.

During my visit, we shot two guns with structured barrels: a 6.5CM AR-10 and a 300NM bolt gun.

We did not do mag dumps or anything that silly.  However, after 10 rounds of rather rapidly fired 6.5CM, the barrel was warm, but not hot.  Temperature distribution was arguably the most remarkable part.  Using an infrared thermometer, it was easy to show that the warmest part of the barrel was around the middle (near the gas block on the semi-auto),  The breech end of the barrel was cooler to the touch and measure at a lower temperature.  Basically, the barrel never got very hot and whatever heat it accumulated was shed very rapidly.

The feel of the recoil impulse is really odd in that it is completely muted and there was no muzzle rise to speal off.  I suspect a part of the was the muzzle brake, but this lack of discernible resonant frequencies made the recoil cycle extremely gentle.  I was shooting an IPSC at 350 yards and the recoil impulse never moved the reticle off the plate.  I fired the last four shots as rapidly as I could pull the trigger.  Everything was on the plate.  The rifle was not light at right around 14lbs with the scope, but I expected a lot more movement out of it even with the muzzlebrake.  Most gas guns have this slight "pitchiness" to them and I saw none of that.

The 300NM boltgun was slightly heavier, but with the much more powerful round the recoil did move the reticle off of the target, but not by much. 

I never lost sight of the target during the reocil impulse and the feel was, again, very muted and controllable.  I am not sure how heavy the boltgun was, but definitely less than 20lbs.  I would guess it was around 17lbs, but I'll check with John.

While both guns were very impressive, the semi-auto shot unlike any other gas gun I have ever pulled the trigger on.  No gas gun ever has a truly free floated barrel, since there is a gas block attached to it.  However, the combination of the structured barrel with a unque way that John has of putting the upper together, is the closest I have seen to date.

He bonds the barrel extension to the upper receiver and then screws a shouldered barrel into that.  The upper receiver is the Aero M5E1 Enhanced since the beefy upper receiver extension helps decouple the handguard from the barrel.  Also, the rather beefy structured barrel needs a large diameter handguard which this is.  The gas block they make is a custom affair that is probably better described as "tunable" rather than adjustable.  It is not designed for making frequent adjustments.  The idea is to tune your gas system for perfromance and reliability, then leave it alone.  I plan to do exactly that.

Since I was heading this way, I brought the necessary pieces with me for John to put together a 6.5CM upper for me.   Originally, I was thinking of doing it in 6XC for local PRS matches, but now that I shot with it, I want to try using it for NRL Hunter as well.  I think I can make weight without too much trouble.  I'll stick with 6.5CM in order to make power factor for Hunter matches.

Saying that I was impressed would be a gross understatement.  The feel of this gun is absolutely unique and it has recoil control behavior of a 25lbs gun in a 14lbs package.  It is quite remarkable.  Now, in the grand scheme of things, with my nearly 300lbs bulk backing up the gun, recoil control is a relatively straightforward affair.  Since my kids were there with me, I had both of them shoot both guns and watched the recoil cycle very carefully.  The guns barely moved even with a much smaller human behind them.

I know it sounds like magic, but it isn't.  I am not a mechanical engineer, but I spent a good amounf of time going over the materials and thinking through what they are doing with these barrels.  The science behind it is pretty solid.  I am not seeing any obvious holes in their foundational reasoning.  The execution is difficult and the barrels are not cheap.  Aside from good ideas, it takes a lot of skill and know-how to make these.  There is a good chance I will make a permanent switch to these barrels on what I consider my "heavy" precision guns while sticking with the Fix as lighter guns they way they were originally intended to be.  When I say heavy, I mean sub-20lbs with everything and light is sub-13lbs with everything (scope, suppressor, bipod).

Before I wrap up, let's get back to the heat management argument for a moment.  The 300NM I shot was significantly accurate and it is at a bit over 2800 rounds.  That sounds outlandish given that is nearly triple of I would expect out of this caliber.  However, if the chamber never gets very hot, it is possible.  I really want to know how long the 6.5CM John is building for me will last.  I have high hopes.

 

 

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