Leupold BX-4 Rangefinding Binoculars

Magnetospeed

Sagebrush1

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I’m looking to purchase one of these Chronographs. Are they reliable and accurate? It seems to me they would be much easier to use than the other type. I understand they will change my POI.

I’m not much into the long range thing, but am getting more into rifle hunting, and as such I’m curious how factory ammo performs at various temps, etc. Plus I have two scopes that I can get a CDS dial for once I establish an average velocity.
 
I have the Sporter model and it does everything I bought it for' It has never dropped a shot which my previous chrono was consistent at doing. Gives me velocity, average, standard deviation and extreme spread. I recommend highly. Also POI shift has been reliably 2" high. Hope this info helps.

Bill
 
I had one. Was plenty accurate and was perfect for confirming velocities without having to move in front of firing line (like the old optical ones). I stopped using it when I switched to a reloading approach which involves more careful tracking of velocities and I hated shooting twice - once for velocity and once for group size, as it did change the barrel harmonics on sporter weight barrels. I ended up with the labradar - it is pricey, but very nice - nothing on the barrel.
 
I have had the top end V3 model for a couple of years now. It is easy to set up and use at the range and very portable. The V3 offers a bit more flexibility than the Sporter but they both do basically the same job. It is nice to be able to travel with a chronograph to measure actual velocity changes at different altitudes and temperatures.
 
I'll echo basically what everyone else said. I've no complaints with my v3 and its hands down better than my previous ones.
 
I sure like mine. It's the Sporter, does everything it's supposed to do. It does effect POI, so you'll want to shoot different groups for accuracy. I think if you could make it stay in the exact same spot on your barrel, the POI shift would be less of an issue. Mine tends to creep forward with each shot, assumable changing POI a little with each shot. It has its own set of trade offs, but it's way, way less hassle than a standard light sensor chronograph.
 
I had one. Was plenty accurate and was perfect for confirming velocities without having to move in front of firing line (like the old optical ones). I stopped using it when I switched to a reloading approach which involves more careful tracking of velocities and I hated shooting twice - once for velocity and once for group size, as it did change the barrel harmonics on sporter weight barrels. I ended up with the labradar - it is pricey, but very nice - nothing on the barrel.
+1 If you can manage the funds, a Labradar is an amazing tool. Can't recommend it enough.
 
I had one. Was plenty accurate and was perfect for confirming velocities without having to move in front of firing line (like the old optical ones). I stopped using it when I switched to a reloading approach which involves more careful tracking of velocities and I hated shooting twice - once for velocity and once for group size, as it did change the barrel harmonics on sporter weight barrels. I ended up with the labradar - it is pricey, but very nice - nothing on the barrel.

Not to high jack this but could you elaborate on the reloading approach you mentioned? I’m about to start reloading so this may be a basic question. How are you accurately tracking your velocity without the chronograph? Ballistic calculators?
 
Not to high jack this but could you elaborate on the reloading approach you mentioned? I’m about to start reloading so this may be a basic question. How are you accurately tracking your velocity without the chronograph? Ballistic calculators?

You cannot track velocities without a chrono. If you’re starting out reloading, shoot for group size and call it good. Don’t get caught up in velocity especially if you’re shooting shorter distances
 
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How are you accurately tracking your velocity without the chronograph? Ballistic calculators?

There are three common ways to chronograph bullet speed - old fashioned optical chronos; the newer magnetospeed device; and personal radar aka LabRadar. I have used all three, but found the LabRadar the best (and the most expensive).

Not to high jack this but could you elaborate on the reloading approach you mentioned?

I have run across several "experts" who say that you can find your most accurate load by looking for "flat velocity areas" as you go up in powder charge weight rather than the more traditional ladder where you are watching point of impact or the OCW approach. In theory, you will find as you move up in charge the fps will go up, but somewhere up the ladder there will be a 2 or 3 consecutive loads with much smaller increase in fps, and that the middle of that will be your most accurate "node". One nice thing about the velocity approach is it reduces the effect of the wind and the shooter's accuracy/inaccuracy on selecting load amounts. Here is a link that discusses the concept:


In my experience, there are 2-4 "velocity nodes" throughout the lowest and highest safe charge range. I have found (and read) that the upper two are either better than their lower counterparts or just as good but faster so most folks will take the highest or second highest node. As such it seems that unless you are really paranoid about overcharge, or totally velocity agnostic, it seems that messing in lower half of book charge range is a bit a waste of time/powder.

Adapting to this, rather than starting at the lowest charge and making 10-13 loads spaced 0.5grain apart, I make 10 loads in 0.3grain increments ending at the max book charge. I also note the max book velocity at max charge. When I shoot I start with my lower charge (typically near the mid-point of the book range). I check every case (and bolt lift) for pressure and I check the chrono velocity as i go up. If I see pressure signs or hit max velocity I stop. From there the data usually shows one or two "flat" spots were 2 or 3 charges don't change velocity much.

Then I pick the best two "flat spots" and then prep 3 each of the mid-point and 2 loads above and 2 loads below the two flat spots in 0.1grain increments (e.g., 40.1, 40.2, 40.3, 40.4, 40.5 + 41.7, 41.8, 41.9, 42.0 and 42.1). I shoot these 30 rounds, do the same calculations and select the best charge weight with a bias for the higher velocity node and loads closer to the middle of the flat spot. I then load 5 cartridges of the selected charge weight to confirm velocity, SD, ES and MOA. The goal is to get SDs under 10 and MOA under 1.0. Without extensive messing around, I can fairly get SDs in the 5-8fps range and MOA in the 0.6-0.9 range for hunting cartridges.

If the magazine and measured COAL give me room to play and I am working on a target load where I want to be in the sub-0.5 MOA range, I tweak the confirmed charge weight by moving seating depth back and forth in 0.010" increments

I am sure there a better ways used by better loaders, but it seems to be working for me.
 
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You cannot track velocities without a chrono. If you’re starting out reloading, shoot for group size and call it good. Don’t get caught up in velocity especially if you’re shooting shorter distances
If you are going for Minute of Deer I completely agree, but if you want more performance the velocities add a lot of good info. In the smaller numbers of shots that average reloader tests, you can fairly easily get a group the groups ok once or twice, but the velocities show significant variance. These loads invariably spread much faster as you start shooting out towards 300-400 yards and also can be more temperature sensitive as they may not be on the "velocity node" flat spot.

Millions of animals have been killed with factory green box CoreLokt and many millions more have be killed with quick and dirty hand loads, but if a guy wants to pursue better performance as part of the hobby, there are fairly straight forward ways to get there.
 
If you get one ( I have one and love it) the only thing I have seen gone wrong is the mounting strap loosening up over repeated shots and the tip of the "blade" raises up and the bullet hits it. I know someone who had this happen... it becomes a paperweight after that.

And I will also add on to the others who posted that it has never dropped a shot. It saves alot of time from setting up the shoot through chrono.

I also found that my tried and true .75 MOA loads out of my .270's opened up to 1.25MOA while the magneto speed was attached, so not horrible as it pertains to accuracy. I use it specifically for the speed node flat spot testing as Viking Guy outlines above.
 
If you are going for Minute of Deer I completely agree, but if you want more performance the velocities add a lot of good info. In the smaller numbers of shots that average reloader tests, you can fairly easily get a group the groups ok once or twice, but the velocities show significant variance. These loads invariably spread much faster as you start shooting out towards 300-400 yards and also can be more temperature sensitive as they may not be on the "velocity node" flat spot.

Millions of animals have been killed with factory green box CoreLokt and many millions more have be killed with quick and dirty hand loads, but if a guy wants to pursue better performance as part of the hobby, there are fairly straight forward ways to get there.


3-400 is short distance and velocity really isn’t going to make a huge difference. I understand that accurate loads should be easier to find around velocity nodes but as a new reloaded I wouldn’t get hung up on it. If you’re stretching things out, sure take a look at it. But as average joe reloader who’s going to sit at the 100 yard line, I could care less about velocity, SD’s, and ES’s. To each their own though.
 
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