This August, the F-Class World Championships were held at the Connaught ranges in Ottawa. This event takes place every 4 years in different countries, and as a relatively new shooter this was my first opportunity to compete on the world stage. Three years of hard work would be tested against 200 of the most competitive long range shooters in the world. As it turned out, I was fortunate enough to take home a bronze medal for 9th place in the individual FTR competition! Shooting with KP Ballistics in the Rutland 4-man team match, we achieved a 2nd place silver medal, out of 14 teams. It was an incredible experience, and a wonderful finale to a year of anticipation. I haven’t written a blog article in quite a while, but I have a great story to share. I decided to start over and change bullets 3 weeks before the competition, and it’s been a roller coaster of load development. Let me explain why, and then you can tell me if you think I’m crazy. I've been pretty busy over the last few months. The business continues to grow, and AutoThrow production has been ramping up quickly. There’s also a match every weekend. Burning out was a possibility, so I planned ahead. My rifle, my load, and my strategy have been stable for quite a while. I made the most of every opportunity to practice, and focused heavily on time management. When Kenny Proulx asked me if I would shoot on his team (KP Ballistics) for the worlds, and try out his new 200 Jack bullet, I agreed, but I wasn’t expecting to let it affect my focus. In this game, the smallest detail can turn things upside down fast. Changing anything last minute seemed out of the question. Like myself, Kenny is a Canadian shooter who developed a great product first, then started a business based on belief in that product. He has a technical mind, and shares my philosophy on the science of shooting. I decided to help him out by developing a load for the bullet, writing about my experience on this blog, and shooting the Jacks for the team match. On paper, the Jack is a 200 grain 30-cal bullet with a BC of 0.357. Like many other shooters who have considered switching to it, I exercised cautious reluctance. Initially, there is a “too good to be true” element to it, since the BC of the new Berger 200-20x is only 0.328. How could a one-man startup from Quebec produce a higher performing bullet than Berger, from scratch? July 7: the EasternsThe Eastern F-Class match was held in Ottawa in early July. It was no secret that this match served one purpose: practice for the worlds. The experience was essentially identical, from the course of fire right down to what you eat for breakfast. I shot my standard 185 Juggernaut load. I fared pretty well overall, finishing 13th out of 40. For the most part, I was able to follow the wind changes pretty well, but I lost a lot of points just outside the corners of the 5-ring. I just couldn’t keep them in the center. Every shot felt just outside my reach in all directions, and it was frustrating. Over the long drive home, I came to a realization. I was not on a path to winning the world championship. Somewhere along the line I had settled, and I’m losing too many points. With a 185 Juggernaut and an SD of 6.7, I’m at a disadvantage right out of the gate. My target is just a little bit smaller than everyone else's. July 18: starting from scratchExactly three weeks before the start of the main event, I fired the first 200 Jack through my barrel. First I calibrated the Two-Box Chrono with three Juggernauts, just to make sure it was aligned properly. Then, the first shot with the Jack at 42.5 grains read 2574, and it put a hole in the paper. I looked at the bullet hole and said to myself, “here we go”. Either this would be the answer to all of my problems, or the beginning of a colossal mistake. One shot at a time, I raised the charge up to 45 grains until the BR2 primer flattened at 2730 fps. There’s my pressure limit. Surprisingly, this occurs at the same powder charge as the 185. These bullets can apparently be pushed faster than you would otherwise expect from a 200 grain bullet, which is a nice start. Then I backed down to 44.5 grains and fired 18 shots. Here are the velocities:
What this string of numbers represents to me is hard to describe. Long range performance starts and ends with velocity consistency. I have fired around 4000 rounds over chronographs in the past 3 years, all in search of consistency. Not every rifle is capable of laser accuracy. For that, you need some luck. My load has never been particularly amazing. What I had was good enough to work with, and I focused on a process to make the best of it. This string of 18 numbers represents potential. After all this time, my rifle may be capable of a flatter long range load than I’ve ever seen. Now I can see a path to winning. July 25: iterative tuning18 shots was enough to get me excited, but this was only the beginning. I needed to find the limits and understand the patterns. As always, I fire a few shots at a time, moving through various velocities and seating depths to learn as much as possible about how the bullet works. Over a range from 43.0 to 44.5 grains, velocities remained very consistent. At higher pressure, velocity starts to jump up, just like it does with the 185. It's comforting to find that, with either bullet, the velocity consistency profile over powder charge is similar. There’s no question that the 200 Jack can produce more consistent velocities overall than the 185. I would guess this has to do with the shorter bearing surface. Less friction with the barrel may have a two-fold effect of increasing muzzle velocity as well as consistency. After realizing that the pressure/charge/velocity relationship was the same as the 185, I felt confident selecting 44.2 grains (2680 fps). At this point, a simple substitution of bullet had reduced my elevation spread due to velocity at 900 meters by 43%. I couldn’t ask for any better than that. With velocity more than taken care of, it was time to turn my attention to group size. With the SD being so great, I don't need any better than 1/2 moa to maintain waterline at long range. Shouldn't be that hard, right? The pattern did not seem like what I am used with the 185. Usually, I expect to see a random scatter that grows and shrinks slowly as you move toward or away from a wide optimal range. A one-hole group didn't jump out at me. Clearly this is new territory, and I have to figure out what’s going on fast. Common wisdom is that some bullets are “easy to tune”. The 185 Juggernaut is one of those bullets. It has a tangent ogive, meaning there is a smooth transition from bearing surface into curvature. This shape will tend to straighten itself in the rifling. It also has a long bearing surface which fits the bore tightly and keeps the bullet rotating around the proper axis. A higher BC comes at a price. If you want a bullet with a higher BC, you sacrifice some of that self-straightening and can expect a more sensitive relationship between seating depth, runout, and accuracy. The Jack is the first time I’ve used such a bullet, and I had to figure this out on the fly. I knew the right answer was somewhere in the 5 to 25 jump range. Jamming produced fliers, and the velocities also shifted. Jumping any more than 25 turned the rifle into a shotgun. Between 5 and 25, the groups all looked the same. The problem is that 3 or 5-shot groups are very misleading when the best load is not obvious. The situation is clear - I need to fire another 50 rounds or so to narrow in on the optimal jump. Normally this is not a problem, but I was running out of time. July 22, 29: provincial matchesOver the next two weekends I travelled to matches in Nova Scotia and PEI, firing 100-150 rounds mostly between 300 and 600 meters, all at the wrong seating depth. I took a guess, and each weekend was a slap in the face. Some of the groups were excellent, but I also lost a lot of points I shouldn't have. Wind conditions were light, so there were only a few points between the leaders. At the longer distances where velocity starts to matter I would catch up relative to the others, but not enough to win. The brass I was using for these matches was brand new, as my intention was to fire-form 400 to prepare them for the worlds. They had been expanded and neck turned, and there is a lot of runout at this point, up to 4 thou at the neck. With Juggernauts that’s not a problem, but I knew the Jack may be more sensitive to straightness. I had numerous people tell me I was crazy to change bullets now, and should get my head screwed back on before the worlds. It was a rough time, but I knew what I was doing. Sanity checkWhat would you do? If you had to choose one load right now, which bullet would you use? This is not an easy question to answer. I thought about it for some time, and ran some calculations to prove the comparison. On one hand, the Juggernauts produce less random dispersion, and in light wind conditions I can rely on the last point of impact as a good read of the true wind. The problem with this is that there are 200 other people shooting excellent rifles. If the wind changes are light, somebody is going to clean every target, and probably win the match by 1 point. I have to expect difficult wind conditions to have any chance of winning. Most people would look at the groups above and say that's terrible, there's no way it could work well at long range. In fact, that's not true. Since my chrono is capable of measuring it, I know the SD is very low, and this tells me the groups are going to stay pretty much the same size as they travel to 900 meters. If you are able to understand a load in terms of dispersion and velocity indepedently, then you can completely predict its performance at any distance. Adjacent to where I always test there is a 1000 meter tree tunnel, with electronic target, that hardly ever gets used. It's great for shooting for fun, but for load development it's not nearly as useful as a Two-Box Chrono and a piece of paper at 100 meters. The major advantage of the Jacks is 25% reduced wind drift compared to the 185. It’s just too much of an advantage to pass up, and if the wind is particularly difficult, as it usually is in Ottawa, it trumps all other concerns. The practical advantage of a higher BC in difficult wind is that the wind changes seem a lot less for you than for everyone else. Every time you just catch the edge of the 5-ring, you would otherwise have lost that point. Those points add up quick. That’s all there is to it. Of course, if I could solve the dispersion problem I would have the best of both worlds. I just had to run some calculations to prove to myself that I wasn’t crazy to abandon the devil I know. July 31: last chanceThe day after losing the PEI provincial by two points, I went to the range to figure this out once and for all. I had been shooting 25, 20, then 17 jump to date, noting slight improvement as I moved closer to the lands. Process of elimination told me 15 jump was my last hope. The groups were pretty rough. For the first time, I felt scared. I was running out of time, but more importantly, out of numbers to try. I pulled out all my targets and looked at them very critically. 5 jump was bad, this is clear. I had fired all kinds of decent groups at 15 and 20 jump, and 15 was better which is why I eventually settled on 17. But wait! I had only fired 3 shots at 10 jump. I had no other data inside of 5 and 15 jump. I had been steering away from it based on those 3 shots alone. This is not the first time I’ve made this mistake. I will sometimes get steered in a direction based on a preliminary result and then solidify an assumption in my mind over time, based on no additional data. As much as I try to keep an open mind, interpreting results and deciding where to go next is hard to do objectively. Now we're talking! In that moment, I suddenly understood exactly what was happening. At least, I had a theory that made sense of everything I have been seeing. The bullet clearly doesn’t want to be jumped. In general, brass expands and releases the bullet at about 2500 psi, and the bullet has moved only 1 thou at this point. “Jumping” is literally that; the bullet is unsupported. If it does not straighten itself, that bullet is in for a shaky trip down the barrel. However, it also doesn’t like to be jammed, or even too close to touching the lands. Velocity increases by around 10 fps, and the groups are not good. I can’t explain why, and it doesn’t seem to happen with the Juggernauts. From 8 jump up to 30, the velocity has settled. So the answer is simply to shoot from 8 to 12 jump, where the velocity is stable, and the bullet is straightest. I loaded the last 10 primed cases I had at 10 jump. In the time it took me to load, a thunderstorm had rolled in. The shack I was loading in was shaking, the sky was dark, and it began to pour rain hard. I needed to shoot! I covered my rifle and ammo as best I could and proceeded to fire my final groups. The wind was incredible. The first 5 shots are in order, left to right. The wind blew the first shot almost an inch to the left and then progressively slowed down. But elevation was holding steady! It's not one hole. It doesn't have to be. As long as these groups are repeatable, with the incredibly low SD, I know that group will maintain at long range. In any case, it's the best I have so far. If you can fire 40 shots within 1/2" at 100 yards, and the SD is 5.0 or better, with a good bullet, you have a load capable of winning the F-class world championship. That's all I needed to see. August 6: loading dayOn Sunday, I loaded 500 rounds at 44.2 grains, 10 jump, as well as some backup Juggernauts just in case. Thanks to the Auto-Trickler I could do it all in one sitting. Then I packed the car and headed to Ottawa the next morning. The moment the last ammo box closes, the time to think about load development is over. Competition presents entirely different challenges. The only thing within my control now is where the barrel is pointed when I pull the trigger. I have to focus on thinking clearly, staying relaxed, and processing as much information as I can. I’ll save the story of my experience in Ottawa for another article next week! I’ll break down my shooting process, plotting methods, wind reading, where I lost points, and what I learned that I will be carrying forward in the future.
13 Comments
Dad
8/27/2017 03:38:22 pm
Extremely well written. I had no idea target shooting was such a scientific event.
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Rod MacKenzieh
8/27/2017 03:52:21 pm
I enjoyed the process you went through & look forward to the Ottawa experience - R
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Corey Edmundson
8/27/2017 03:55:47 pm
Adam- I love your blog and reading it. I am new to long range shooting. Fairly well versed in pistol and short rifle though-however the idea of shooting my new rifle 1k+ excites me. I do not have a mentor yet and your blog is so well written and easy to understand I feel that you are my next door neighbor. Thank you so much for writing about your experiences.
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John Matthew
8/27/2017 04:34:17 pm
Great report Adam, I'm in the process of tuning the 200 jacks myself and really welcome your comments, like you I've struggled a bit but your comments have put me back on track, many many thanks John. (uk)
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Eric Christianson
8/28/2017 12:54:52 am
Nicely written, could you tell us about your rifle and optic?
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Adam
8/28/2017 10:32:35 am
Scope is Sightron SIII 10-50, with 1/8 moa clicks (very important)
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Greg Nielsen
8/28/2017 01:10:14 am
Enjoyed the read
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Adam
8/28/2017 10:32:00 am
Thanks. It's a Barnard P, with Kreiger 10 twist.
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Dave Boreham
10/4/2017 10:15:30 pm
Great to meet you in Ottawa Adam, let me know when 7mm Jacks become available!!
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Gerhard Hamman
10/12/2017 06:13:27 am
Adam it was a pleasure meeting you in Ottawa. The Auto Throw works great and cuts reloading time considerably. I am re-gearing to use the 200 Jacks and your blogs are very helpful. I understand each chamber is different but what cartridge base to bullet ogive length did you end up with for the 200 Jacks; and how did this relate to same for the Berger 185's?
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Adam
10/16/2017 08:15:47 am
Hi Gerhard. Great to meet you as well. It's hard to give you a number because the comparators we use are all slightly different. The Jacks require a short throat relative to what you would normally use with the 185. My Jugs were seated so the bearing surface was almost all the way to the neck/shoulder junction and the Jacks bearing surface then seats about halfway (about 2-3 mm longer).
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Gerhard Hamman
10/17/2017 12:30:14 am
Thanks Adam. Depending on the jump the 0.135" freebore reamer on order should then possibly be fine. It is slightly longer than the 0.120" freebore Kenny suggested. I will provide feedback once the new barrel is fitted.
Tom McDonald
7/15/2019 04:09:07 pm
I am intrigued by your assertion that the case neck expands at 2500psi or .001" of bullet travel. Do you have any recommended sources for that data? Thanks
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Who am I?Adam MacDonald: Canadian FTR shooter, inventor, problem solver. Archives
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