DarkLordOfOptics
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Guns, Optics, 2nd Amendment and resisting the Left in everything they touch.
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Prismatic Magnification

As this is written, I am firmly ensconced at the Raasay distillery on the Island of Raasay among the Inner Hebrides islands off the western coast of Scotland. I got lucky with the weather and this place is absolutely unbelievable. Some of the most beautiful views I have seen to date and incredible hospitality where I am staying.
What do you think is on my mind among all this beauty and hospitality? Well, mostly the fact that I miss my family. They are half way around the world. The original plan was to bring them here with me, but due to unforeseen circumstances it was not in the cards this year.
While that is what I am mostly thinking about, the issue of prismatic magnification is still lingering in the OCD dominated parts of my brain, so let's get it out.
I went and looked a little bit at FOVs and size and weight of what's out there. I also went and looked at the FOVs of different thermal clip-ons since that also makes a difference.
The FOVs of thermal clip-ons I have looked at in the last couple of years varied from about 6 degrees to 17 degrees and almost everything in between.

That is not hugely helpful, but if we assume you are willing to lose some thermal FOV when using a thermal monocular as a clip-on, we can narrow it down to the range of 6 degrees to 9 degrees. That gives you roughly QVGA pixel counts when in front of a scope with most configurations.
Let's look at how that matches to the FOVs of common modern prismatics that I have been discussing over the last however many months.

Compact 3x prismatics from PA, Burris and Vortex are in the 7.2 to 7.4 degree range.

SwampFox Trihawk is a large prism design so it has 3x FOV of nearly 10 degrees.

ACOG 4x32, crappy eye relief and all, has 7 degree FOV.

Elcan OS 4x that is arguably my primary prismatic to date, has 6 degree FOV and weighs right around 17 ounces with the mounts.

Large prism 5x Saber from SwampFox is almost 6 degrees as well and ~25 ounces with an integrated mount.

The new 5x30 prismatic from Element should be a bit less than that, but likely close to 5.5-6 degrees and about the same weight with the mount. I think the Element might be the best one optically this side of an Elcan, but I will withhold judgement until I get a full production model here. It does have the best reticle of the bunch, of course (not that I would be biased about that, of course).

With small prism 5x scopes like Burris RT-5, PA SLx 5x and Vortex Spitfire Gen2, the FOV drops down to ~4 to 4.3 degree range, so performance with a thermal clip-on begins to suffer.

With 6x prismatics, we do not have a whole lot of reasonable datapoints, but PA has introduced a fairly compact 6x magnifier as did Vortex. A magnifier is essentially a prismatic scope without a reticle. Both of those have FOVs of just under 4 degrees. That's pretty usable, but not great with a clip-on.

I hope you are still with me after this entire stream of numerical unconsciousness.

There are a few things we can draw from this. One is that if you can bear the weight and plan to use a thermal clip-on, a large prism design might be worthwhile.

If you want magnification, a larger prism design with magnification of more than 5x will get a little unwieldy, unless you go with an ultrashort eyerelief scope. Those do have their place, but mostly on airguns. Element has a few coming up and I might look at them. Until then, large prism 5x designs are about as heavy as I'd want to go.

Even when at the same weight as an LPVO, prismatics do handle better simply because the weight is a bit further back. This handling advantage is further extended when working with a clip-on. It ends up being a lot closer to you. With a clip-on like Burris BTC-50 that has a rear-biased mount, I can fit both the prismatic and the clip-on on the upper receiver without touching the handguard (picture attached).

Where does that leave us? If compatibility with thermals is important stick with 3x or 4x prismatics, preferably with large prisms.

That gets you a lot of capability in a comparatively compact package.

Looking at FOVs of high quality LPVOs, like SAI6 1-6x24, it turns out that small prism scopes like the micro 3x and 5x prisms give you similar FOV to LPVOs, but for less money and weight.

Large prism designs, get you a wider and more immersive FOV than an LPVOs at the same magnification but weight becomes comparable (that will all change if I convince someone to make me an LPVO for ARs only with consistent 2.2" FOV).

This is where you have to be clear with what you are looking to do.

If for you this is a choice between an LPVO and a prismatic and you are looking to save some money, get a large prism 4x or 5x design. You will have an excellent experience with the image, wide FOV and reasonable compatibility with thermals. You might even be able to get away with the new 5x designs. I certainly plan to give them a shot. Once the 5x scopes from Element get here, you'll understand why.

If LPVO is not in the cards because of weight concerns, but you need some magnification, 3x scopes are looking good. Again, you retain good compatibility with thermals and add significant ability to positively ID and engage targets at distance at very low weight.

Small prism 5x designs are not a lot bigger and if you do not care about clip-ons they have their place. They are less expensive and lighter than LPVOs. What gives me a little bit of a pause is that I am clearly more comfortable shooting offhand on 3x than on 5x. Interestingly, larger prism 5x scopes mitigate that to a good degree with larger eyebox and massive FOV.

Is there such a thing as a medium prism design? It is not like there are only two prism sizes out there. Well, Elcan 4x I have is sorta that. If it had an adjustable eyepiece, it would eventually end up buried with me right next to the 3-15x50 Tangent Theta (there must be something in the water in Canada). The optics on that thing are glorious.

The truth is that there is only so much FOV I am willing to give up for magnification. With LPVOs, I can always turn the magnification down, but with a prismatic, I'd rather err on the side of keeping the FOV even if that means a little less magnification or a little more weight.

I wonder if I can get someone to make me a dual power 2.5x/6x prismatic....

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5x Prismatic Wrap-up

This is not the end of my commentary on 5x prismatics, but it is a wrap for an unintentionally very long term project I had. I spent an unhealthy amount of time evaluating these four prismatic riflescopes:
Element Immersive 5x30 https://alnk.to/gzXEPUr
Swampfox Sabre 5x36 https://alnk.to/aAPTubq
Vortex Spitfire Gen2 5x https://alnk.to/3co4hVD
Primary Arms SLx 5x https://alnk.to/2jOhnT7

Two are large prism designs. Two are small prism designs.

The order in which I list them above corresponds to the image quality, from best to worst, although there isn't a ton of difference between SLx and Spitfire Gen2. Purely on the merits of resolution, Sabre is comparable to them as well, but much wider FOV and forgiving eyebox does put it a step above in terms of performance (at the expense of about a pound of weight). Element Immersive 5x30 is a different beast optically and it should be at a higher price at which it sells. It resolves better, has higher contrast and widest FOV of the bunch. Side-focus adds ...

00:16:40
Blast From The Past: Millett ZoomDot RDS

I dug this thing up purely by accident. It has been a long time since I used it for anything, but I am thinking I should, especially as I work on a magnifier video.

MIllet's ZoomDot was a unique red dot sight that had auto brightness and variable dot size from 1MOA to 10MOA.

Early ones, like mine, were made in the US. Millett had some aspirations of selling these to the US military.

I do not think they got very far, then the company was bought by Bushnell and essentially shut down after a little bit. At some point, the manufacturing for the ZoomDot moved to China and it was not really the same.

00:05:44
Scout Scopes: Burris 2.75x20

Scout scopes are almost like a forgotten art form these days. There is an occasional discussion either on how they are the greatest thing since sliced bread because 1) THE colonel said so 2) if you do not think they are, refer to rule number 1.
Alternatively, the prevailing thought is that they are completely useless and if LPVOs existed in Jeff Cooper's time, there would never be such a thing as scout scopes.
The truth, as is usually the case, resides somewhere in the middle.
Scout scopes do have their place, but they are definitely a niche product. It is, however, an interesting niche.
Scout scope pickings are relatively slim in terms of what's on offer.
Leupold makes a 1.5-4x28 https://alnk.to/gKSibYj
Burris makes a 2-7x32 and 2.75x20
Vortex has a 2-7x32 in the Crossfire line
There are also a few out there from UTG, Aimsports, etc.

I strongly lean toward compact fixed power designs, so Burris 2.75x20 https://alnk.to/cSJCBQx is probably my favourite and is the subject of this ...

00:11:58
Livestream later tonight and upcoming raffle

I made it back to some semblance of civilization in Colorado, but only for one night. Tomorrow, we will head into the Rocky Mountain National Park for a few days of camping and I am not sure how spotty internet connectivity is going to be.

My original plan was to do an impromptu sort of a livestream on my takeaways from the match I just shot, but given what has been happening in the Middle East, it is probably more pertinent to talk about that.

I am going to start by rehashing a little bit the narrative of how we got to the current situation and where the latest events are likely to taking us.

As far as the match goes, they did a random drawing for the prize table, so Ethan and I both walked away with something. Since both of us are very much industry insiders, I am not sure how appropriate it would be for either one of us to keep stuff off of the prize table.

That means that I will raffle off the items we picked up during the next couple of livestreams.

One is a $2000 OFF certificate for...

BOTC prizes raffle

As I mentioned yesterday, Ethan and I picked up a couple of items off of the prize table at Burris Optics Team Challenge, which I will be raffling off.

Both prizes were provided by Burris for the prize table which we should all appreciate. Without sponsors, shooting sports would not develop the way they have.

1) $2000 off MSRP certificate for Burris XTR PS 5.5-30x56. This was Ethan's pick, so you can say this is courtesy of Burris and Q.

2) Burris Fastfire 4 was my pick. I have one of these and like it. I've got mine set up as an offset RDS on a nice DMR-ish rifle.

If you would like to be a part of this raffle, please send me an email at

[email protected]

Make sure the email has your name and whether you are going for the XTR PS certificate or Fastfire 4. You can not go for both.

Is anyone excluded from this raffle? yes. Youtubers and influencers. There are a few on this email list and, for the same reason why I think it is inappropriate for me to take anything ...

Current Events

Gentlemen,
I am trying to decide if I want to do a livestream to discuss the current events in the Middle East.
Every time I do that that, the feedback is rather conflicting.
If I do, that will be tomorrow evening (17th), around 7PM Mountain Time.

Please vote and add a comment if there is something specific that interests you or your reasoning.

A morning with a chronograph

When I tell people that I am using Hornady's factory ammo for matches, I get occasionally surprised looks.  Occasionally.  Most of the time, I get fairly condescending looks from handloaders who would not let a factory round pollute the chambers of their precision rifles if their lives depended on it.

To be fair, if I had the time, I might be reloading as well.  I might be able to do better than modern factory ammo, but the truth is that I am not a quarter MOA shooter, so a lot of that would be lost on me.  The UKD matches I fidn most interesting can be done by a competent shooter with a 1MOA gun.  I am working on that first part.  I reload when I have to, but if I can get factory ammo that's not outrageously expensive and that shoots well, I will go with that every time.

I looked around and realized that I have about 600 rounds of Hornady 147gr 6.5CM factory ammo from two lots.  400 rounds from one that I will use during the match later this month.  The remainder I will likely use up practicing prior to that.

I woke up early and snuck out to the range while my family was still asleep earlier today.

I set up in the 100 yard tunnel we have.  I took my four shots to zero with the lot I plan to use for the match.  Then I fired a six shot ~0.7MOA group.  That's accurate enough for my purposes.

Here are the chronograph results:

It is slow, but accurate and consistent.

Then I shot a five round group of Hornady 147gr ammo from the other lot.

Both of those lots are not too shabby for factory ammo.  POI was within 0.2mrad between the two lots, all laterally.  

 

I had some other ammo on hand, so I fired two five shot groups with Berger 144gr hybrid target ammo and Sako TRG 136gr.

Here is what I got for five rounds of Berger:

That's not a ton of statistics, but it is a data point.  The group was ~1.1MOA

 

Here the data for the Sako TRG 136gr ammo:

This ammo showed some mild pressure signs, but not too significant.  

Again, this is not a ton of data, but Hornady is looking pretty decent here.

I'll repeat the zero retention and consistency tests a couple more times between now and June 18th when we head to Wyoming.

I might pick up a couple more boxes of Hornady 147gr from a different lot to get some more data.

More to come.

 

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First PRS Match is behind me
High Noon at Del Norte

My first PRS match is officially behind me.  It was, I think an officially sanctioned regional PRS match at the shooting range called Del Norte about an hour from me (just east of Rio Rancho).
As I discussed previously, rather than using the rifle I originally prepared for it, I ended up having to change gears at the last moment and slapping a 5-25x56 Tangent on my daughter's 6ARC MiniFIx.  A lightweight 16" Proof barreled 6ARC is not an ideal set up for PRS competition, but, in the grand scheme of things, the rifle did hot hold me back at all.  I had a couple of weights that fit the Q-cert handguard, so I slapped them on there as well, which got the rifle to right around 12lbs.  The balance point was almost where I want it, but not quite.  In all other ways, this was a very handy rifle to shoot.  I am actually thinking of getting a couple more weights that I can stack on it (Sawtooth weights are stackable), so that I can shoot some future local matches with it.  It shoots Hornady's Black 105gr ammo very well (it also shoots 108gr ELD-M and 103gr ELD-X well, but I had a larger supply of Hornady Black ammo on hand).

It chrono'ed pretty consistently for factory ammo.  Here are the measurements for a 20 shot group.

If I were to take out the fastest shot, SD drops down to 8fps.  

In terms of wind performance, it is a 5mph rifle, so slightly better than the 308 ammo I was going to use originally, but not as good as the 6.5CM that was my intended match rifle for this year (we make plans, but then life happens).

I do have to admit that I really enjoyed shooting the match with the MiniFix.  So much so, that I am seriously thinking of building another one for myself, since this rifle is technically my daughter's.

The closest shot we had was a bit over a couple of hundred yards.  The furthest was around 1150.  That was a bit challenging for the 16" barreled 6ARC, especially since the terrain there is tricky and wind is doing strange things.  Morning was relatively quiet wind-wise, but then the wind becamse gusty with changing directions.

It was a one day match with about 30 shooters (six squads) and ten stages.  The 17 year old kid who won the match was in my squad with his dad.  Apparently he is on the US team, so it should not be surrpising that he won.  He was very good.

Overall level of the shooters in the match was quite good.  I really was not sure what to expect.  Somewhat paradoxically, the only matches that I have shot in so far are the much larger two day NRL Hunter matches.  In those, I am just out of the bottom third in terms of skill level.  In this match, it was pretty much in the same spot, I think.  

The terrain was a little bit like Cameo, I think (I have been there, but not shot there), with some angle changes and sufficient vegetation to make getting on target occasionally troublesome. 

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Getting back on the horse, little by little

My original plan was to do a livestream on Thursday of this week, but I think I'll push it out to next week.  A few days at home is doing wonders for my recovery, but my voice is still not quite there.  I do not think any of you are looking to listen to me cough for two hours straight.

Also, I am going to try to shoot that local PRS match this coming Saturday, so doign a livestream next week after the match is likely to be more productive.  It is my first one, so I fully expect that I will screw it all up.  It should be a good learning experience.  I do not have a dedicated PRS rifle and I am not looking to set one up jsut yet.  If I like it, I'll put something together, but as far as competition goes, my focus is really on UKD matches like NRL Hunter, Competition Dynamics, etc.  My 6.5CM is not back yet, so I'll just shoot it with my 308 FIx.  It is not ideal, but it will do just fine for my purposes.  I am in no danger of winning anything either way and this will stress my ability to read wind.  A secondary purpse here is that I am not 100% certain what rifle I will take on a mule deer hunt with later this year, but it will be either something new to test or this 308.  Now that I think about it, the 308 is going with me regardless either as a primary rifle or as backup.  The rifle shoots, so if I miss, I know it is on me.

For the match, I have Burris XTR PS 5.5-30x56 scope on the 308 Fix.  I think the way they did the heads up display in these is a meaningful improvement over conventional riflescopes.

https://alnk.to/d3EjPHC or https://alnk.to/8iVRlGN

Optically, I think XTR Pro is a little better, but the EO integration in the XTR PS is, I think, in advantage.

In parallel, I am looking at the replacement AAC ammo (they replaced the faulty ammo and I have chrono results on it) and testing the optics of the 40mm scopes in parallel.

 

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