Favoring Fishtails: LE Advanced Sniper School Day 2, Part 1

I woke up pretty sore in my legs, shoulders, chest, and back from the previous day’s stalk. It got me thinking that regular stalking would not be a bad as part of an exercise regime. Note that while I had generally been keeping up on my physical training, in the weeks leading up to the class I had been sick for some of it, and super busy for the week just before. I had not really slipped, but I was not in the regular exercise groove that would have kept me from getting sore for the most part.

We went to the range and had a discussion on coordinated fire. This is when two or more snipers fire simultaneously at the direction of a team leader as part of a coordinated larger movement. Following the discussion we were given a compressed window of time to prepare to fire on an array of targets placed at 200 yards downrange. Being that I was odd man out, Matt, a friend of one of the instructors, acted as my partner. After a brief count 8 rifles barked out simultaneously. A neat side effect of the coordinated shots was that we were knocking down the stationary steel IPSC silhouettes (they’re not supposed to fall down). I would score a nicely centered up head shot, watch the target fall during recoil, and have the bolt cycled before the target hit the ground.

The instructors noted that all of the shooting we had done up to that point had been in the prone position using bipods. They also noted that in most cases in real life setting up in prone isn’t possible. Paper targets were set up with a 5” outer square and a 2.5” inner square and we went back to 420 yards. The only rules were that we couldn’t use the prone position. Even if we had wanted to use prone, there was tall grass blocking the view of the targets from the ground.

I worked with reverse kneeling for the first several 3 shot groups. I used my BMF (Bag, Multi Function) as a front rest with the bag mounted on the Harris bipod. On the rear of the rifle I had a Magic Sack to brace the rifle on my right leg. Neither of the bags add anything to the perceptible weight of the rifle.

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My typical 3 shot group was just under 2 MOA. I was generally calling my shots somewhere within the outer 5” square. Being that my rifle now seems to shoot 10 shot prone groups at just at or slightly above 1.5 MOA, 2 minutes from a field position sounded pretty good. It was then that I remembered that I was comparing apples to oranges. John Simpson did some work with a computer simulation that would take a shot group of any given number of rounds extreme spread and extrapolate the size of a group with a different number of rounds. Without slipping any of John’s trade secrets, suffice it to say that it tells what we should already know. If you keep firing after 3 rounds your group will get larger.

The wind was similar to the previous day. The first time I used the wind from my location, ~4 mph from 11:00 and plugged it into Shooter. I put in the 0.3 mil left correction. After a walk to the targets I found that my group was centered up at approximately 6” left, strangely almost equal to my correction, indicating that had I left my sights alone I would have been centered up. I walked back to the firing line figuring that I would be good to go if I set the windage turret to 0.0 and held dead center. My next group was approximately 5” right. This went on all day.

I figure that my experience with horizontal deviation could have been due to on or both of two likely causes: chasing pieces of a larger group and the wind changing. I figure that there was some of both, but based on my observations throughout the day, I believe that that the larger component was wind was subtly changing direction. The corrections I was making were 15 to 20 minutes old by the time I fired the next group.

If you stand in one spot with the wind coming from a general 12:00 direction you will notice that the direction shifts from moment to moment, probably something in the neighborhood of a shift from 11:00 to 1:00. A full value wind (3:00 or 9:00) is much easier to account for, because even if the magnitude varies the correction will still be in the same direction. The point of impact will be off by the difference between the inputted correction and the actual necessary correction; this might play out to be the difference between a 10 mph dominant wind condition and a 14 mph gust. At 420 yards my ballistics program tells me that, given a 3:00 wind, my 10 mph correction would be 0.9 mils and my 14 mph correction would be 1.3 mils, a difference of approximately 6” at 420 yards.

If the wind shifts from 11:00 to 1:00 between the time a correction is figured and the time a shot or group is fired, the wind effect and the correction will be compounded, essentially doubling the error. The correction for a 10 mph 11:00 wind at 420 yards is 0.6 mils left. Its mirror image, a 10 mph 1:00 wind requires a correction 0.4 right. The numerical difference is due to the spin drift function being turned on. When I turned it off the correction for both was 0.5 mils. If I’m shooting in fishtailing conditions in a constant 10 mph wind (I might as well be shooting with the tooth fairy) that is fishtailing from 11:00 to 1:00 between my sight input and my shot, I’ll be off a full mil, which at 420 yards is just over 15”. Even with only a 5 mph breeze I’ll still be off a half mil.

It’s tricky wind conditions like these that make Russ’ advise to favor or hold to one side of the target effective. He also recommended that I use the tall grass about midrange as a wind indicator. Of course, this was already something I “knew”. This brings to mind that one of the things that kept happening repeatedly was that I would hear something that I already knew, but it would come to me with a different emphasis or insight that had not made it so important before. The reason I think holding or favoring is good advice is that it encourages the shooter to define the hold based on real time conditions, rather than trying to mechanically apply a book number to a dynamic situation. Russ’ combat experience also reinforced to him that simple methods that can be applied under stress are vastly superior to complex ones that are too difficult to apply on the two way range.

After getting consistent results from supported reverse kneeling, I noticed that one of the snipers was getting very good groups, consistently sub minute (probably 3”). I asked him what he was doing to get such consistently good results. He was shooting from a supported standing position, bagging his rifle in on a truck tool box. I decided to try something similar, so I used a cooler near the rear of the truck bed to rest my front bag on, and put my rear bag on the wall of the truck bed. I could tell that this was much steadier, giving me a wobble area of approximately 2” at the 420 yards we were at. This position is essentially what has been called “parapet prone”, and was used in trench fighting. It has more in common with prone as far as technique and steadiness than it does standing.

On the last group of the day, my windage turret was set to zero, and I stupidly and bull-headedly used the last group as my wind indicator, when I could plainly see that the grass was telling me the opposite. There obviously comes a time when experience trumps theory, and I would have been better served to pay attention to what my eyes and little voice were telling me.

One thing I noticed with both of the supported positions was that the rifle’s recoil impulse was consistent and the deviation of the sight picture through recoil was minimal in comparison to my bipod prone position. Similarly, movement of the rifle through recoil was minimal, my called shots were consistent with their placement in the groups, although my groups showed uniform horizontal deviation from the wind. I suppose the idea that I’m trying to convey is that the positions were solid. This was likely due to getting my body mass square behind the rifle and leaning into it a fair amount. The tension resulting from the forward lean also means that the firing hand can release its grip to cycle the bolt and there is still sufficient tension between the rifle butt and the shoulder to keep the rifle stationary through the bolt cycle.

The shooting part only made up the first half of day 2. I’ll cover the remainder in the next article.

5 thoughts on “Favoring Fishtails: LE Advanced Sniper School Day 2, Part 1

  1. Regarding the longer shots in the fishtail: what is the magnification range of your scope, and at what power did you use for these shots?

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