GUNSITE XLR CLASS & BULLET TEST PHASE 2
As discussed in the previous thread regarding the 338 Bullet Test, part 2 took place at Gunsite the week of March 26th. We started off the week with the Gunsite XLR class instructed by CoryT and later were joined by instructor Mike Hughes to assist in the bullet test.
The initial phase of the test took place in the LV desert using the Acoustic Chronograph from Josh & Francis, this test was to feature a second acoustic unit however the operator of that unit was unable to attend due to a medical emergency. So we made due on the velocity side of things using a PVM 21 chronograph at the muzzle. (see conclusions of the original test below)
The objective of this test was to get an idea of the potential accuracy of the bullets at distance. This included shooting them on paper at 500, 1000, and 1500 yards. We had 3 large target boards constructed and they featured a 12" POA using the standard Gunsite style paper target. There were several shooters and a variety of platforms to use. The barrel twist rates ranged from 1-8 on a 338 SnipeTac to 1-11 on an AI AWSM. We also had a custom Rock Barrel in 1-10 and an Accuracy international AX in 1-9.5 for the test. We tested several different bullet types from solids to jacketed bullets in order to determine the accuracy potential at distance.
We started out on Monday at Gunsite for the XLR, during this class I was shooting the Predator 235gr Solids loaded from SouthWest Ammo. When I arrived at the airport Zach met me to hand over a box of pre-loaded 338LM so I can use them for the test. In the previous XLR I used the SouthWest 250gr Scenar load with excellent results out to 2000m. My average velocity for those rounds were 3050fps. This time they had enough Predator Solids thanks to Stephen from Dynamic Research. He was instrumental in his support for the test. I was shooting these solids out of my Accuracy International AWSM (1-11 twist).
As stated our instructor for the class was Cory Trapp. I have taken this class from Cory previously and was looking forward to taking it once again. He has great teaching style and is a wealth of knowledge. This is not a beginners class and luckily we had great group of students which assisted in moving the class along. I think during the class all the right questions were asked, and believe me this makes a difference. One area of focus is the primary differences between shooting inside 1000 yards and shooting beyond 1000 meters. We really focused on the latter knowing a lot of what we don't see at 1000 yards would definitely show up at 1500 yards. Everything was designed to arm the student with the knowledge to get accurate, precise hits at distance in as few shots as the accuracy of the system would allow.
After the initial briefing we headed to the 300 yard range to check zero, calibrate our scopes and get an initial drop number at 300 yards. This was designed as a starting point so when it came time to calibrate our system at distance we would be in the ballpark, as calibration started the next day at 600m.
The afternoon of the first day was spent in the classroom pouring over the information necessary to get those hits on steel. At Gunsite, even during the XLR Class they use Man Sized targets, the maximum width being 22" wide. We were not going to be shooting oversized targets, or rocks in the desert, but target that meant something. In fact a majority of the targets had 10" flash plates in the center, hitting one of those at distances beyond 1000m showed you had sub moa precision.
We started Day two on the Calibration Range. It is called that because there are a variety of targets with calibrating water lines which allowed the shooter to fine tune the drop so you have a precise aiming point. The targets are arranged in a way that can easily be considered a UKD target, even though the ranges were readily available too us. Because they were placed out among the natural terrain it was very different from being placed on a square range. There are no range flags or yard markers to work with.
One side note to consider with the solid bullets. Spotting impacts on steel is very difficult. There is no doubt when you hit a target, however you do not get a splash like observed with a jacketed bullet. You get the smack but you have to be on your game to have an idea of where that hit is. The solids simply make a dime sized mark on the steel without the splash and at distances beyond 1000m with the heat and mirage, an accuracy spot can be and is very difficult, so I recommend using paper for solids. Being off in your call even a few inches will make a difference downrange.
A positive training feature at Gunsite is the fact they encourage the students to spot for each other. This helps in seeing and understanding the conditions. How they change and how they affect the bullets downrange, it's a positive training tool. As well they also encourage those with similar bullets to par up and work together. Before heading out we all used our Ballistic Computers to dope a 10MPH wind, then everyone's drift was put on the board so we could see who might work together. It was also encouraged for students to share ballistic data and when possible install multiple profiles on their ballistic computers. Several of us had Nomad's with Field Firing Solutions, and others had phone Apps, this gave us a good opportunity to check both. I personally ran both FFS and BulletFlight Side by Side so I might compare the results.
Gunsite is a target rich environment and we used multiple shooting stations to engage the targets. Changing positions changed things like the distance to target as well as the aspect of the wind. Even small changes in the wind have a huge effect downrange when shooting beyond 1500m and each student got their fill of targets. There was no shortage of targets and we were allowed to engage them as long as necessary to fine tune our data.
The evening of the second day we had a Night Fam Fire using Cory's Ashbury 308 and assorted NV equipment. Everything on the line was designed to observe, range and engage a UKD at night with the aid of various NV equipment. We engaged 8" Plates at 400 yards and then a man-sized target at 800 yards in total darkness. The Ashbury 308 was dead on and each shooter was able to engage targets as much as they wanted.
Day 3 UKDs
This was UKD day, we moved to a slightly different area of the range and out among the natural terrain were a series of camouflaged painted man sized targets that we would have to find, range and engage. When I say camouflage, I mean they are not painted white or black but highly colored to match their surroundings. We started off finding a prominent terrain feature or in this case we had a worn Pepper Popper out in the middle that was not hidden we used a reference point. (12" Wide) The Popper was right around 1200m and from there we created our personalized range cards If you look at any of the photos included, especially the shooting positions, you'll see a combination of PDAs and Databooks. Information is king at any range and it was important to record as much data as possible. I personally have details on my range card page, my field sketch page and in my Shooter's Diary pages. Then everything is calibrated in my PDA so the profile for the bullet used is as accurate as possible. Not only was I recording the position, the environmental conditions but also the magnetic azimuth to the target. It's not like shooting inside 1000 yards where you can let things go by the wayside and still get solid hits. We took our time and triple checked the data not only against the computer but against the others in the class. We wanted the highest number of first round hits possible and believe me that is not easy in a UKD setting on camouflaged targets that were just under 2MOA in size. A shooter could essentially hold on a target and fire 3 rounds that were shooter perfect and still expect to get 3 different results based on the conditions and how they changed from shot to shot.
As the day progressed we got better and better understanding the system and conditions. I think overall the class managed about 1/3 first round hits, with a but over another 3rd second round hits and finally we deemed that 3 rounds was probably a realistic number to strive for at extended ranges to successfully hit a target. One note about these targets, they are not place in a position were you can see every potential impact off the steel. Because they mixed into the natural terrain is was possible to send a round off the shoulder of a target and have it impact behind a hill. Or to find follow the trace towards the target only to see it get lost in the brush around it. The arc could look dead only, only to miss to and disappear into the trees behind the target. There were also times, especially in the mirage at extended distances, the shooter would call a hit and the spotter was unable to confirm. When this happened we asked the shooter to send another and more times than not a hit followed. This was the true learning moment in the class, that even when you missed a target, the shoot was executed so well that the follow up was 100% predictable giving you a solid second round hit. Being repeatable was better than getting lucky, although we were all happy to take the luck when it was handed too us.
For me, the SouthWest Ammo Predator Solids were outstanding. I found I was off slightly with my calibration data, however I was able to adjust on the fly and once I had solid numbers in my Databook I was able to match that up with my PDA so by the end of the day, when my allotted ammo was running low, I was able to get a series of solid 1st round hits between 1250m to 1500m. It made it much easier to simply hit the target, and when the Predator Solids hit the swinging plate centers of the targets you knew it. They smacked them pretty darn hard. Overall I was super satisfied with the performance of the Predator Solids downrange, with my farthest target engaged was 1980m on Day 2. I managed a 3rd round hit at this distance. When we choreographed on the morning of the first day, the load from SouthWest had an SD of 7… granted it was a very small sampling but 7, please I can't do that myself. And these are loaded to magazine length, a huge plus for those shooting a tactical rifle.
For those reading this, and interested, right now we are planning another Gunsite XLR Class in October… We will keep you posted but plan on mid October 2012, around the 18th I believe.
Bullet Testing Part 2
After the XLR Class finished the plan was to use the remaining 2 days of the week to shoot the various 338 bullets on paper at distance. We had a variety of bullets and loads from the 338 SnipeTac to a 20" AX. All the bullets were and are commercially available and if they were not provided by the companies, in many cases we purchased them with our own funds. We shot them under real conditions recording the MV of each shot and where possible the impacts downrange on the sheets of plywood with the aiming point targets stapled to the boards. As noted above every shot was put through a PVM 21 chronograph and recorded, this way the data could be combined with the actual drop to determine a true / real world BC for the load combination. This is understood to be a bit subjective, there are factors which could adjust that BC based on the speeds and the system used, but combined with the testing conducted during phase 1 of the test I think we begin to see a pattern emerge. Our main concern when looking at groups downrange was there vertical spread for the given load. There were also cases where a particular bullet did not like the speed and twist rate of one barrel and actually performed a bit better in another rifle, also another consideration.
I am gonna start at the top, because the bad was just that. Let's face it, shooting XLR is not cheap, is not easy and not readily available to everyone. So getting where you want to go as soon as possible should be a consideration. If you don't mind custom building a system and then working up load that fits your system, you can do that, but it will cost you. So what we are hoping to do is get you on the road to success as soon as possible. We understand, you can probably make anything work and work well, especially if you have unlimited resources, but not many people fit in that category. So here is what we found.
1. Overall Winner: Hornady 285gr
Both boxed and hand loaded overall this was the best bang for the buck and gave everyone excellent results downrange. From my 1-11 twist barrel to the 9.5 Twist of other rifles this combination produced at all distances to well within Sub Moa accuracy standards out to 1500 yards.
This was the load both Cory T and Curt D used in their rifles. Cory with an Ashbury ASW (1-9) and Curt using a Dan Shumway Custom Built Rock Creek Barrel (1-10). Our conditions were varying but needless to say you can start at 65 degrees, 25.5 Baro, 48% humidity and a 3-5 MPH wind.
For a measurement at 1500 yards Curt managed to shoot a group that had a 9" Vertical dispersion and 14" Horizontal. His loads, I believe were running at 2745fps I have more data that shows 2840fps which I believe might have been Cory's velocity. Cory shot a group at 1500 meters that was 10 Inches Vertical and 9 inches of horizontal in size. I believe a good starting point for their loads were right at 92grs of Retumbo. This remained the most consistent bullet the entire week. The BC used was right around .720 which puts it pretty well up there. At a 1000 yards this bullet in Curt's rifle group 5 inches vertical and 8 inches horizontal, so the consistency was certainly there.
When it comes to a jacketed bullet easily found, this was by far the clear winner in our opinion.
Winning Solid Bullet
2. 235gr Dynamic Research Predator (SouthWest Ammo Load)
I used this bullet all week and I have to say it didn't disappoint. With a muzzle velocity out of my AWSM (1-11) of 3115fps, this bullet gave me a BC of .575 in FFS and .625 in Bulletflight. At 1000 yards I shot a sub MOA group shown above and at 1500 yards I shot a 14" X 8" group using 13 Mils of elevation. My dope at 1000 yards was 6 Mils and as you can see centered up perfectly on the target. It was really a struggle with the solids and they are very particular with the condition of the bore. I highly recommend if you are gonna shoot the solids you start with a spotless bore, and do not mix and match. I saw the groups open up to 1.5 MOA just by shooting 5 rounds of jacketed in between. So it was necessary to clean the bore to stay consistent.
The nice part about this load was it worked from the start, we had to tweak a lot of the other bullets to get measurable performance at all distances. This was not the case with these, Like the Lapua offerings as well as the Hornady the Predators worked out of the gate. And they hit extremely hard.
Jacketed Recommended List
Most of the jacketed bullets were working well for everyone. They all hovered around 1 MOA with several loads producing Sub MOA results at distance. We found a few that opened up a bit more at 1500 yards when compared with their 1000 yard group, and it was not as linear as the two above. In order of Recommendation from me personally, understanding your mileage may and probably will vary.
1. 250gr Lapua Scenars
These are the standard and I think they work well in almost every rifle. If you want to get off the ground running fast the 250gr Scenar is the bullet for you. Most people were pushing them anywhere from 2950 to 3050fps with the 20" AX sending them downrange at 2765fps. They are very forgiving and averaged a vertical spread about 15" @ 1500 yards.
2. 300gr Bergers
Another solid performer, these were being pushed between 2700fps and 2800fps depending on the rifle and load. They maintained just just around 1 MOA of accuracy at 1500 yards and while most noted a bit harder to get a good seating depth, they were still solid even from rifle to rifle. Even the 20" AX was able to get solid results at distance with them sending them downrange at the 26oofps (Avg) which used 54MOA to reach 1500 yards.
3. 300gr Lapua Scenars
Also a very solid performer, much the same as the Bergers but a bit more forgiving when reloading. Both Scenars are solid, get you up and running asap performers. No issues at all.
4. 250gr Berger Bullets
These tracked very well with my 250gr Scenar load. If you don't have a pet load featuring a 250gr bullet, this is an excellent choice. I was using H1000 and H4831sc with these and while I believe my velocities were bit low at 2925fps I think they were accurate. Because they were new I need a bit more with them, but I think they are an excellent alternative to the 250gr Scenar with a higher BC. The reported BC appears to track with the manufacturer, and I suspect getting them over 3000fps will be much more rewarding. I loaded them both magazine length and over CIP lengths and they both worked well, with a 3.830 being the best for me personally.
5. 300gr SMK
These were shot by Bruno out of his SnipeTac 338. So their velocities were closer to 3100fps and were a solid base line for him. To my knowledge no else was shooting these, so unless someone has some other data that was missing from mine, we only have information based on the Snipetac. What I have recorded here was 3.7 Mils 1000 yards with this bullet, however I believe Bruno was running an offset zero. I know when he moved to shooting Solids we used the SMK to gauge the performance.
Well we can't have a winner without looking at what didn't work for us. Part of the reason of this test in the first place to try and end some of the "in-fighting" happening between the bullet makers, mainly the solid bullet guys. There were reports of bullets not making it downrange and twice we saw that. We had bullets working at 1000 yards and hitting sideways at 1500, as well we had bullets that barely held minute of Arizona, yes you read that right. Minute of Car was a tough slug for some. No before the world gets up and arms, understand these bullets were sold, to consumers with the understanding they work, I suppose, money was certainly exchanged on them. Also we tried them several different ways when possible. Bruno had his reloading set up in the car and we attempted to mix up the conditions in hopes of getting favorable results paying attention to the recommended specs provided by the literature. We shot them from the 1-11, a 1-9.5 and then finally in the 1-8 twist SnipeTac. Believe me the solids beyond 1000 yards were hard to work with, and in my humble opinion too specialized, too finicky and not really worth the effort at this time. Can that change, yes, but for now, only time will tell as we have not given up them.
I know I said wasn't bringing any GSC bullets but Bruno had them loaded in his SnipeTac. Now before I get too deep here, we have video of some of the shooting and testing we did. Not a lot because there was a lot to manage, but we have video of this. The SnipeTac was pushing the 338295SP142 at just over 3000fps, and again as stated we used a 1-8 twist. My understanding is, Bruno bought quite a few of these, and they were sold with the understanding of what rifle they were going in. That is important point remember because I am not 100% of this model was being modified or changed, whatever, but he bought and paid for these. Looking at the results my first thought was, "Now I see what all the fuss was about", and the level of protest was to shut everyone up. It was reported by Jeff that they grounded at 750 yards and we read quite a bit of debate regarding this, well let me say, they hit the ground at 750 yards. We started off unable to get them on paper and moved to a berm at 1000 yards with a car on it. In the middle of this berm was a piece of concrete and Bruno sent round after round trying to hit the middle of this berm with a car on it. Nothing, no matter what he tried, holding, dialing the rounds hit the ground in front. Finally I said to him to load his 300gr SMK into the rifle and send that, which quickly went to 1350 yards over the top of the car. So we gave up, and Bruno basically pulled the bullets with a set of pliers. I get it, there is supposed to be a new version of this, and there very well maybe, (as yet unseen) but come on. You sold this guy a ton of bullets with the understand they would fly. Unless you are offering a refund to people with the "older version" or free replacement, I think that is poor form.
Here is the "not counting them out part" in the first test where I shot them we were told we were going too slow, now I am sure we will be told we are going too fast. Okay great, I have the spec sheet from Bruno which says it is suited for all 338 calibers and gives a MV of 2850fps although not specifically, and as for twist rate I see nothing that states a 1-7 as ELR Researcher told me. I have 50 rounds of these same bullets, and using an 1-9.5 I believe I can get them to 2850fps for a final try, but honestly I think anyone considering these should wait and see. Two different groups shooting different varieties of 338 with the same results. And as an example of Bruno's reloading prowess, he broke out his 300NM and shot a 4" group at 1000 yards cold. Like, "hey let me try this" and bang, he had less than a 1/2 Minute group on paper. So the man has reloading talent, forget about the fact he spoke to them on it. Our results matching the others, to me, says a lot when you look back at the debate that raged on here.
The Cutting Edge out of my AWSM. They hit the ground at 600 yards, right behind the 500 yard board. One appeared to evaporate in mid air, but I was the only one who thought they saw it. Bruno then replaced his GSC Load with the Cutting Edge bullets and they appeared to work well at 1000 yards but again were a bit inconsistent at 1500 yards. We had a tough time getting any two rounds to land in the same place. These appear to need a fast twist and high velocity. I would suspect out of a 375 CheyTac they would better, but in a 338LM I think you'd be hard pressed to get great results. Maybe with a bit more R&D they would fly better, but given the limited quantities we had, they were skipping across the landscape. If I am reading the data correctly based on our short hand they appeared to be grouping 26" of vertical at 1000 yards. That at least put them on paper with the SnipeTac.
The Rocky Mountain load also worked at 1000 yard, but had a very difficult time at 1500 yards. These impacted the wood at 1500 sideways, and we ended up again trying them in the SnipeTac where we had much better results. It appears the more off conventional they got, the more twist and speed you need to maintain stability. It's not hard to see if someone was shooting them at distance, it could appear they were working and with more load development I think they have potential, but with much more effort. The sheet of plywood told the tale much better as it allowed us to see the results. Again with such limited quantities it is really hard to have something we know will work first time out of the gate. And it was interesting that we had what I would consider an acceptable group at 1000 yards but they fell apart at 1500. The MV used was 2750fps and our spread was just about 20" at 1000 yards, so 2 MOA. So I would not write these off, but you have to consider the out of the box results we got with the 300gr bullets above, more is better in this case. Really I think the quantity was our enemy, more time, more bullets we might have been able to get sub moa accuracy, but then the expense and time goes up versus the others.
Finally the LeHigh 245gr Bullets, again, a quantity issue. We had very few of these left and had mixed results at distance. Muzzle velocity out of my rifle was 2825fps which was not extremely slow, but wasn't great either. These were left over from the initial Bullet Test so they were loaded more for safety than anything else. I know greg was shooting them out of the 375 Chey Tac but otherwise we had very little data to go by. Just not enough of them to get a solid fix on what they were doing downrange.
So that is the good, the bad and ugly of it. Again, I want to Thank Cory, Mike and Gunsite for an excellent week of training and shooting. To SouthWest Ammo for some awesome loads. It was an outstanding time and we all learned a lot. There was a lot of data to digest, as well once you move beyond 1000 yards, especially on paper it was clear to see everything changed. It's not easy by any stretch of the imagination and with limited quantities with a few of these loads, not being able to fine tune them, hurts the bottom line.
Bullet Test Part One Results
Finally what everyone has been waiting for:
KnS Ballistics Services reporting the results for the 338 Bullet Demonstration as moderated by Snipers Hide
Listed below are the supersonic averaged G1 and G7 Ballistic Coefficients for the seven bullets used during the 338 bullet demonstration held on December 10th, 2011 in Nevada. The bullets are listed below in the random order in which they were tested.
Bullet 1: 300gr Sierra MatchKing – Manufacturer reported BC – 0.759 averaged G1
Acoustically determined BC – 0.747 G1 and 0.380 G7
Bullet 2: 285 gr Hornady BTHP Match – Manufacturer reported BC – 0.720 averaged G1
Acoustically determined BC – 0.685 G1 and 0.348 G7
Bullet 3: 245 gr Lehigh turned solid
Acoustically determined BC – 0.651 G1 and 0.333 G7
Bullet 4 – 232 gr GS Customs SP turned solid – Manufacturer reported BC – 0.686 averaged G1
Acoustically determined BC – 0.578 G1 and 0.298 G7
Bullet 5 – 235 gr Predator turned solid
Acoustically determined BC – 0.556 G1 and 0.282 G7
Bullet 6 – 300 gr Berger Hybrid (Gen II) – Manufacturer reported BC – 0.816 G1 / 0.418 G7
Acoustically determined BC – 0.766 G1 and 0.389 G7
Bullet 7 – 276 gr ZA turned solid – Manufacturer reported BC – High
Acoustically determined BC – 0.719 G1 and 0.362 G7
For more details about the acoustic chronograph and BC discussions see the following pages.
Acoustic Chronograph Details
The basic idea of the entire test procedure is to use acoustic sensors to measure the bullet’s time of flight to various distances. Each bullet fired has the muzzle velocity measured with a chronograph and then passes over microphones placed at four downrange distances. Due to the types of bullets tested and terrain of the test facility, microphones for this test were placed at 313 yards, 487 yards, 1093 yards, and 1264 yards. The raw data for each shot is in the form of a sound file which shows spikes when the bullet passes over the microphone. Also during each shot, the atmospherics are carefully monitored using a Kestrel 4500. After all the test rounds were fired, the post processing of the sound traces begins by using custom written computer programs in conjunction with a custom written ballistic calculator. After the time of flight for each round fired has been calculated from the data traces; this flight time, atmospheric conditions, and muzzle velocity are entered into the pre-processor for the ballistic calculator where the drag of the projectile is varied until the calculated flight time conforms to a best fit match of the experimentally observed time of flight. This process is repeated for each individual projectile that was fired during the test. This process allows you to determine the unique shape of the drag curve for each bullet.
For this test, the results are presented as ballistic coefficients averaged over the supersonic realm of the bullet. Since we are using acoustic sensors, it is impossible to determine the ballistic coefficient of any bullet when it is subsonic. We also did not test for subsonic transition stability due to safety reasons. Further post processing of the acoustic data can result in velocity banded ballistic coefficients is possible, but as of yet has not performed on the data from this demonstration.
Discussion of Acoustically Determined Ballistic Coefficients
Many shooters are aware that Bryan Litz has previously developed his own proprietary acoustic chronograph and has published two books containing acoustically tested ballistic coefficients of many different bullets. Mr. Litz has tested some of the same bullets that were used during this test, and published the data in one or both editions of his book, Applied Ballistics for Long Range Shooting. We are pleased to acknowledge that a substantial portion of our data correlates with the Litz data to within acceptable experimental errors. Mr. Litz published that the averaged G1/G7 of the 300 gr SMK is 0.745/0.381, while our test calculated a averaged BC of 0.747/0.380. Another bullet tested during this demonstration and by Mr. Litz is the 285 gr Hornady BHTP match bullet. Mr. Litz reports an averaged G1/G7 BC of 0.699/0.358. Our test determined an averaged G1/G7 BC of 0.685/0.348, a difference of only 2%. Another common bullet to both tests is the GS Customs 232 gr SP solid lathe turned monolithic solid. Mr. Litz reported an averaged G1/G7 BC of 0.604/0.309, while our test data produced an averaged BC of 0.578/0.298, a difference of 3.5%. These results show that both the method used by Mr. Litz and the method used during this test are equivalent.
There is a notable disparity between the reported ballistic coefficient(s) for the Berger 300gr Hybrid Generation II projectiles. This caused some consternation as the other data that can be compared to Mr. Litz's tests shows very good correlation. As a result of that disparity the data has been checked 3 distinct times to look for any human error during post processing (with none found). Perhaps at some later date Mr. Litz and KnS Ballistic Services will have the opportunity to discuss the issue at length and endeavor to explain the anomalies noted.
The raw data files and details necessary to process the flight times are available to each of the respective manufacturers upon reciep of written request. We will not distribute the raw data traces other than to respective manufacturers and/or their authorized representatives.
KnS Ballistic Services would like to extend a big thank you to Mr. Galli of Sniper's Hide, Mr. Trapp of Gunsite Academy, Mr. VanNiel who independently supported this test and was instrumental to the coordination effort with KnS Ballistic Services and Sniper's Hide to get this demonstration moving. Thank you to the Sniper's Hide members and sponsors (specifically SouthWest Ammunition and Zethilius Assoc) for the generous donations of projectiles and loaded ammunition. A number of other supporters took time from their weekend to come out and assist with setup, logistics, and break down of the test. Without all of the endeavors of everyone, this would have been an impossible undertaking. We look forward to future testing and offer our assistance and services whenever necessary.
KnS Ballistic Services, LLC.