THE HISTORICAL FUTURE OF THE 50 BMG
By Craig Martin
“It simply does not have the ballistics to compete in Extreme Long Range (ELR)”, “The round is old and antiquated, hell, it has been in military service for over 100 years”, “It is nothing more than a machine gun round”, etc. I could go on, but I think you see where I am going with this! The 50 BMG has more than its fair share of nay-sayers and doubters. I will concede that some of the above statements are true. Yes, the big 50 has been around for over 100 years. Yes, this behemoth of the small caliber class continues to enjoy a stellar and unblemished career in the military. But I see some of these statements as accolades, not insults.
My intent in this article is to encourage the reader to take a fresh look at this cartridge. After reviewing all its attributes, both positive and negative, make an educated assessment as to its ability to compete in ELR competitions. It is my sincere belief that this round is far from antiquated and inferior to the numerous fledgling calibers that have spun off the 50 BMG, also known as their parent case. I have absolutely no desire nor intention to disparage other calibers, especially those derived from the 50 BMG’s DNA. Rounds such as the 416 Barrett and the 460 Steyr are well designed and very capable of contacting steel at extreme distances. All I ask is that you consider the merits of the parent before solely embracing her offspring.
Full disclosure, I am an active member and current Vice President of the Fifty Caliber Shooters Association (FCSA) and I work for a Norwegian owned company (Nammo) that manufactures 50 BMG ammunition for the military. Therefore, it is fair to say that I am probably a little biased when it comes to this historical and modern piece of artillery. Personally, I feel I have simply been privy to its true capabilities and as a result, it has earned my admiration and respect. But this article is not about opinions or feelings, it is about theories that can be proven or contradicted. A custom rifle, whether built for hunting or competition, is purpose-built with numerous traits in mind.
But one of the most, if not the most, important characteristic it must possess is accuracy. As I stated in my opening paragraph, many people see the 50 BMG as nothing more than a machine gun round. Sure, you will eventually hit your target, when one or more of the 25, 50 or even 100 belt fed rounds you launched from your tripod mounted M2 happens to collide with the area in which your muzzle is pointed. Many people not familiar with the 50 BMG see it more as a “spray and pray” platform rather than as a round capable of benchrest accuracy.
ACCURACY
This is a good place for us to dispel the first “inaccurate” rumor regarding the 50. The smallest five (5) shot group ever recorded in a 50 BMG competition was shot by Lee Rasumssen and measured 1.9557 inches (0.187 MOA). This certainly is not my definition of “spray and pray”, but it is going to take more than one tight group to dispel this deeply rooted perception. Perhaps you are asking yourself, “was that just an anomaly or is that type of accuracy repeatable”? Maybe Patrick Bieck can answer that question for us, but I think he already did. In August of 2014, Patrick shot a slightly larger group, one that measured 2.045 inches (0.195 MOA). Keep in mind, these are not 3 shot groups fired from a few hundred yards away. Each record group fired in an FCSA sanctioned match consists of 5 rounds fired from a distance of 1,000 yards.
Do a few, albeit really good, groups define a calibers accuracy? No! But nearly 40 years of benchrest competition and thousands of sub-MOA groups fired in sanctioned matches do. These sub-MOA groups fall into two different categories, “Screamers” and “Yellers”. A Screamer is defined as a five (5) shot group measuring less than seven (7) inches (0.668 MOA) while a Yellers is a five (5) shot groups measuring approximately ten (10.47) inches (1.0 MOA). To add a little perspective, there were 36 Screamers and 154 Yellers shot in the 2023 World Championship. Numerous impressive groups are recorded in regional matches each year as well. For example, in March of 2023, a FCSA sanctioned match was held in Shreveport, Louisiana. Even though this match only had 15 competitors, there were a total of 5 Screamers and 26 Yellers shot. The smallest Screamer shot in this match was 4.250 inches (0.406 MOA).
With so many Screamers and Yellers being shot each year, the FCSA decide to find an additional method of rewarding competitors for their 50 BMG marksmanship skills. Approximately a decade ago, the 50-5X Club was created. Any competitor who kept all his or her shots in the X-ring would be recognized with a special patch and entry into the Club. As of 2022, this achievement has been recorded in sanctioned matches over fifty times!
A well-made 50 BMG rifle can even make me look good every now and then. The below picture is one of my best groups. I shot it at the 2023 World Championship in Raton, New Mexico. It measured 3.375 inches (0.322 MOA); but now that I think about it, it is not that impressive when compared to Lee and Patrick’s groups. Oh well, as you can see in the below picture, my wife and target puller, was proud of me.
Photograph by Dianne Martin: 50-5X (3.375”) shot by Craig Martin on July 1, 2023
Not to sound like one of my favorite television shows, but I think we can declare this myth: busted! The 50 BMG can be loaded for extreme accuracy. In fact, I cannot think of another caliber whose accuracy has been better documented than that of the 50 BMG.
BULLET DESIGN AND BALLISTIC COEFICIENT
Accuracy at 1,000 yards is one thing, but does it have the ballistics to accurately hit targets at 3X or even 4X that distance? If you are firing an M33 ball projectile from a machine gun, no, it probably does not. This is where I think her service to our country and other NATO members has tarnished her reputation as a contender in the world of ELR.
Gunsmiths never get the notoriety or recognition they deserve. Fortunately, I have been blessed with two of the best in the business. Martin List (Tryon, OK) and Shawn Broussard – Titan Precision (Iota, LA), have built all my custom rifles. There is a quote I have often heard Shawn say, “Accuracy is all about barrels, bedding and bullets”. I do not know if he is the originator of that quote, but as usual, he is 100% correct!
Bullet design, manufacturing, and materials have greatly improved over the last twenty years. Thanks to the popularity of the 50 and the continued efforts of the FCSA, the 50 BMG has not been left out of this trend! When I first started shooting the 50 BMG competitively in 2013, the 750 grain Hornady AMAX was the most popular projectile on the firing line. Fast forward ten years, and it is a rare occurrence to see these multi-part projectiles used in competition. As in the other competitive calibers, most of the 50 projectiles are lathe turned monolithic aerodynamic works of art made of either copper or brass.
There is one parameter, over all others, used to compare the quality and efficacy of competition projectiles. That parameter is the Ballistic Coefficient, more commonly referred to as BC. Simply put, the BC of a projectile is its ability to overcome the resistance of the atmosphere in which it is fired. The better its ability to cut through the air and delay the effects of resistance, the higher the BC. There are two commonly referenced units of BC, G1 and G7. Since this article is not intended to be an in-depth look into the history, evolution, and variations of this critical measurement, I will simply say that all BCs referenced below are G7.
It is not uncommon to see the Applied Ballistics staff at a big ELR match. They are certainly the experts when it comes to measuring and understanding external ballistics. If you are fortunate enough to be at a match where they are performing Personal Drag Models (PDM), get your name on the list and pull out 10 extra rounds for testing. The information they measure and provide in your PDM is extremely beneficial in predicting the flight pattern of your ammunition fired out of your gun at various distances. In addition to receiving a printout of your PDM, it will be uploaded to their Bullet Library and may be downloaded at any time in the future to your Kestrel or other ballistic calculator, provided it has Applied Ballistics capabilities.
The below table (Table 1) summarizes and compares some of the results from various PDMs. My 50 BMG PDM is compared to two of the most popular cartridges used in ELR competitions. Again, I am not trying to convince the reader to choose the 50 BMG over any other caliber, especially the 416 Barrett or the 460 Steyr. Both cartridges have excelled in the sport and have demonstrated and proven their mettle in the ELR arena. What I am saying, is that the 50 should be considered when choosing an ELR caliber and that bullet innovation and design for this seasoned round has advanced at the same rate as its younger counterparts.
I realize that this table does not tell the full story and can even be misleading. For example, do not read too much into the last two rows. While Extreme Spread (ES) and Standard Deviation (SD) can certainly be indicative of an accurate load, it should not be an indictment on any of the calibers listed in Table 1. For one thing, they are all very low, and I would expect each of these loads to be very accurate. Low ES and SD is more the result of how well the load is matched to the gun in which it is being fired. For this article, we are concerned with which calibers are well suited for ELR, not reloading and how well the load compliments to the rifle.
As we move our way up the table from the bottom two rows, we come to gyroscopic Stability Factor (SG). According to the Berger Bullets website, “shooters who are interested in maximizing performance at long range will need to select a twist rate that will fully stabilize the bullet and produce an SG of 1.5 or higher”.
As you can see in the table above, poor stability is not an issue in any of the PDMs listed. It is my opinion that this number only tells us that the twist rate of each barrel was sufficient to properly stabilize the projectile.
The story is really told in the upper rows of the table. Obviously the 50 BMG has the heaviest projectile. While I am not surprised that this massive 800-grain projectile was slower than the two 460 Steyr, I am very surprised it was faster than the two 416 Barretts used in this study. In fact, my goal when I began this project was to push an 800-grain Cutting Edge Laser projectile, 3,000 fps or faster in an accurate and safe manner. To say the least, I was a little skeptical if I would be able to accomplish this feat. However, as you can see in Table 1, this big girl can move!
Therefore, while she is 71 fps or 2.3 percent slower than the fastest load in the table (a 460 Steyr, PDM
Designator: RO11KPSU2), she is also 165 grains or 21 percent heavier than that same load. Sticking with our comparison of the same two loads (PDMs), the 50 has a BC of 0.527 while the Steyr is approximately 3.2 percent lower with a BC of 0.510. So, what do all these numbers mean in the real world, or at least the world of mathematics (see Table 2)?
The above table (Table 2) summarizes the effects bullet weight, ballistic coefficient and muzzle velocity have on the exterior ballistics of each caliber (PDM) selected for this study. As can be expected, the high muzzle velocity of the 460 Steyr (RO11KPSU2), yielded the flattest shooting curve out of the 5 PDMs in the study. This 460 Steyr, which had a muzzle velocity of almost 3,100 fps, required an elevation adjustment of only 54.0 MOA (or 15.7 MIL) to reach a 2,000-yard target. However, the 50 BMG in this study was not far behind. The 50 required an additional 1.8 MOA (approximately 3.3 percent increase) in elevation to reach the same distance.
In third place, for flattest shooting, was the other 460 Steyr (PDM Designator: 01200) which required an additional 3.4 MOA in elevation over its faster counterpart. While the two 416 Barretts came in fourth and fifth, requiring an additional MOA elevation of 4.2 and 4.8, respectively.
Based on the numbers we reviewed in Tables 1 and 2, we can conclude that the 50 BMG maybe one of the flattest shooting rounds in its class. While one version of the 460 Steyr slightly eclipsed it in trajectory, the other cartridges based on the 50 BMG bolt face did not. The slower Steyr (PDM: 01200) required an additional 1.6 MOA or 2.9 percent increase in elevation and the two 416 Barretts required an additional 2.4 MOA (4.3 percent) and 3.0 MOA (5.4 percent), respectively, to reach the same distance as the 50 BMG.
PRESSURE
I knew I could not scrimp on the gun powder if I was going to reach my goal of launching an 800-grain projectile at a muzzle velocity greater than 3,000 fps. But I did not want to lose my eyebrows, or worse, in the process!
The journey to reach my goal safely started with the selection of a long barrel and a slow powder. Starting with a low powder charge, I meticulously analyzed every bolt lift and primer for signs of high pressure. Fortunately, I found the perfect load without having to borrow my wife’s eyebrow pencil!
As I mentioned in the beginning of this article, I work for a company that manufacturers 50 BMG ammunition for the military. Since I have access to the equipment, I decided to measure the actual pressure generated by my less than conventional and spicy concoction.
Photograph by Craig Martin: Test barrel equipped with pressure transducer.
For safety reasons, all firing in our test range is done remotely. As soon as I pulled the lanyard that released the hammer, the crack and audible return from the barrel was noticeable. The standard, military issued 647 grain M33 ball is loud, but nothing like this.
With some hesitation, I glanced at the screen and nearly gasped at what I saw…70,000 psi! This can’t be right, or can it? After I thought about it, it started to make sense. The upper acceptable pressure limit for ball ammunition is 65,000 psi. Sure, my pressure is higher, but I am shooting a projectile that is more than 150 grains heavier. The pressure should be higher, right?
Time for a second opinion! The first name that came to mind was Nikki Croasmun with Cutting Edge Bullets. Sure enough, she was quick with an answer and my fears were put to rest. She said that 70,000 psi did not surprise her at all. In fact, according to her, most ELR loads likely have higher than standard pressure.
Therefore, through qualitative and quantitative methods, I have determined that this 50 BMG ELR load is high, when compared to most published limits, but is safe in my gun.
RECOIL MANAGEMENT
So far, we have dispelled several myths regarding the 50 BMG. We have determined that is just as accurate, if not more accurate, than many other large ELR calibers. In addition, we discovered that modern 50 caliber projectiles have one of the highest ballistic coefficients and can be flatter shooting than many others in its class. And if all of that was not enough, it turns out that the high pressure generated by the ELR 50 is safe and possess no significant hazards when fired in a properly built firearm designed to chamber this caliber.
Time to move on to yet another myth that seems to follow this platform: recoil management. Perhaps it is because the 50 BMG is the largest caliber you can own without a permit. Some states do not even allow you to own or possess one of these firearms. But for some reason, many people think the average 50 BMG delivers punishment from both ends of the gun. The truth is, she has a lot of bark but not as much bite as most people think!
Don’t give me that look! Yes, I know I just said that the 50 BMG has lower than expected recoil. And I stand by that statement. I am not saying that it has little to no recoil and I acknowledge that some 50s simply are not pleasant to shoot. Newton’s Third Law is still valid when it comes to the 50 BMG. “Every action has an equal and opposite reaction”, and an 800-grain projectile traveling more than 3,000 fps is one hell of an “action”.
However, the “opposite reaction” generated by that “action” is greatly mitigated by the weight of the rifle and a large, properly designed muzzle brake. Fifty caliber rifles have extremely large brakes that are necessary to redirect the gasses generated from the burnt powder. I have always said, when it comes to 50 BMG muzzle brakes, shoulders love ’em and neighbor hate ’em. When placed on the firing line, adjacent shooters usually grimace and then begrudgingly move or place a barrier between themselves and your big 50. Always be courteous to your fellow shooters and give them time to move or make necessary adjustments. The blast from the brake can be quite annoying and even dangerous in some situations.
In addition to the brake, the weight of a custom, long range 50 BMG rifle, which is between 45 and 50 pounds, helps reduce the recoil felt by the shooter. This is the primary reason you will not see a 50 BMG in the King of 2 Mile competition. With a current weight restriction of no more than forty pounds, the potential of the 50 is significantly hampered. It takes a lot of steel to stiffen a long barrel with a half inch hole in the middle of it.
A good muzzle brake and a heavy rifle with a sprinkle of shooter knowledge and experience will easily allow you to maintain your position behind the scope. Even if you do temporarily lose sight of the cross hairs during recoil, you will have plenty of time to get back on the rifle to see an impact or a miss. A flight time of several seconds gives you plenty enough time to recover your shooting position.
SPLASH
No myth to bust here! If you are having trouble seeing impacts and misses, throw a bigger chunk of metal out there. When it comes to large projectiles, the 50 BMG is your Huckleberry!
If every metal target was surrounded by dry, powdery dirt, we would not be having this conversation. However, sometimes these AR500 gongs of delight are positioned right in the center of lush vegetation.
Shrubs and grass can easily swallow up a rapidly falling projectile with no visible sign of gastric upset. Add these conditions to a hot, humid day in the South and watch your blood pressure start to rise. There are two words that will frustrate a shooter more than any others, “No Call”. Now what do I do? I guess the only thing you can do, send another, and pray that you or your spotter will see where it hits.
You will not always see the splash from a 50 when it contacts a solid object. But you have a much better chance of seeing the disruption caused by an 800-grain projectile as opposed to a 550 or even a 635-grain projectile when it loses the fight with gravity and returns to earth!
BARREL AND BRASS LIFE
It is hard for me to address the longevity of the barrel on a 50 BMG ELR rifle and the brass used to feed it. I am honestly in uncharted waters and simply do not know the answers to those questions. However, I can give you some information based on my 50 caliber benchrest rifles and what I have seen so far in my ELR rifle.
I have some RWS brass that I am still using and have currently reloaded 22 times. This brass is used in FCSA or benchrest competitions, and therefore has been exposed to less pressure than my ELR brass. While I am shooting a similar projectile (802 gr MTAC) and I am using the same powder (RL50), the charge weight in my ELR brass is 4 grains higher. After three (3) reloads, I have noticed that the primer pockets on my RWS brass used for ELR, are starting to get a little loose. Not all of them are loose and the ones that are loose, are still capable of holding a primer securely.
As far as barrel life is concerned, the barrels on 50s usually enjoy good longevity. I say “usually” because I do not know if this spicier ELR load is going to have a negative effect on the life span of the barrel. Personally, I do not believe it will. However, only time will tell if a slightly higher powder charge results in a measurable difference in the rate of throat erosion.
Normally, I get between 2,000 and 2,500 rounds through my benchrest rifles before I replace the barrel. Not because I have seen a reduction in accuracy, but because I stop trusting them. While I cannot prove it at this time, I believe I will see similar numbers with my ELR rifle.
To conclude this segment, with a barrel life of approximately 2,000 rounds, the 50 should be as good, if not better, than most of the calibers used in ELR Heavy Class competitions. At this point, I am not going to make a prediction on the life of the brass. All cartridges used in ELR are subjected to extreme pressure. While some will do better than others, brass will eventually fail. Fortunately for 50 caliber shooters, high quality brass is readily available.
CONCLUSION
As an ELR shooter, we are blessed with a plethora of very capable firearms and cartridges from which to choose. We are in our infancy with a bright and exciting future ahead of us. Hundreds of companies constantly introduce the latest, greatest products promising to help us conquer the thousands of yards that lay between us and our targets. Ballistic technology will continue to evolve and promises to aid us in our quest.
While I do encourage you to embrace technology, I implore you to not completely abandon the past. Sometimes the answers we seek are standing right in front of us. The 50 BMG will never be one of the sexy new calibers. She is not the pretty new girl that all the guys in school want to date. But maybe it is time to rediscover this historical beauty?
Certainly not the only choice for shooting ELR, the 50 BMG is a solid platform and may even excel is some categories. Thanks, in part, to the continued innovation of match projectiles, the 50 is capable of benchrest accuracy and has a high ballistic coefficient. The higher pressure and heavy projectile of the souped up round does not translate into the bone shattering recoil some claim. In fact, the weight of the rifle coupled with an effective muzzle brake will mitigate this recoil and reduce it to a manageable shove. All these qualities, along with extended barrel life, availability of high-quality components, and enhanced visible splashes resulting from impacts and misses, makes the 50 BMG a caliber that should at least be considered when building an ELR rifle.
The future of this historical masterpiece has yet to be written, perhaps you will be part of it?
- Craig Martin
