Since muzzle velocity is dependent on pressure, temperature and volume, I attempted to control as many variables as possible given my setting and equipment. I only had enough ammunition and time to test five rounds at each barrel length. The IMI Samson 150 grain FMJ is a 7.62x51mm NATO spec cartridge. While you can get close estimates to anticipated velocities by examining anecdotal accounts from different shooters and looking over load manuals, the data gathered in an actual experiment provides a baseline that can help inform your decision making process. So in quick summary the .308 Winchester also known by it's military name the 7.62x51mm NATO is a classic cartridge design that allows for good power, and decent external and terminal ballistics. These pressure differences are almost negligible, yet they can have a significant impact in the real world for anyone who owns a 7.62-chambered firearm or who likes to reload their own ammo. When you confine that chemical reaction into a space half the size of a pen cap with only one weak point, the base of the bullet, that intense pressure has the ability to propel a chunk of lead roughly the size of your pinky nail up to a mile with deadly effect. He,he. They were fairly close. Compare that to a 5.56 Ball M193 round's 55 grain bullet, which delivers a . Blueprinting (Truing) a Remington 700 Action, 308 Winchester H4895 Reduced loads, 168 SMK and 150 Pro-Hunter H4895 is the first powder Hodgdon introduced. To make the test even more interesting, four different types of .308 Win factory ammunition were chronographed at each barrel length. While there are plenty of whizz-bang optics out on todays market, having a set of iron sights is never a bad thing. The vast majority of rifles, carbines, and pistols chambered in .308 Winchester can safely sling 7.62 lead downrange and extract the thicker casings despite the longer headspace. Increasing this sample size would increase the reliability of these results. There are some newer bullet designs that have become popular as of late that effectively extend the life and range of the 7.62x51mm NATO/308 Winchester even further. Articles may contain affiliate links which enable us to share in the revenue of any purchases made. Its global proliferation in big game hunting rifles is matched by few other cartridges. ATTENTION: Effective Sept 1, 2020, the BBTI Project is in "Archive Status." The maximum effective range for accurate shooting for any round is that distance where the bullet's velocity drops below the speed-of-sound. The .308 Winchester round shoots pretty flat out to 200 yards when it starts to drop. Published Mar 29, 2021 12:55 PM EDT. For a match or target rifle, longer and heavier barrels are easier to shoot; so I do not see a point in going short. In the next frame you can see the gun recoiling (below). class bullets. data for your own use. The 7.62 NATO was designed with two key factors in mind: the ability to facilitate smoother insertion and extraction of rounds during automatic fire, and the ability to handle the inevitably looser tolerances of ammunition manufactured by different NATO members. My 16.5 308 Winchester (above) is a fun little rifle. .32 Winchester Special, .308 Winchester (7.62mm NATO), .38-55 Winchester, .243 Winchester, .300 Remington Short Action Ultra Magnum, .25-35 Winchester, 7.82mm (.308) Lazzeroni Patriot, .260 Remington, .307 Winchester, 6.17mm (.243) Lazzeroni Spitfire, .356 Winchester, 6.71mm (.264) Lazzeroni Phantom, .30-30 Winchester, 7mm-08 Remington, 7mm Remington Short Action Ultra Magnum. According to multiple non-scientific studies, the average .308 case weighs in around 160 to 170 grains each, while 7.62 brass usually comes in at over 180 grains apiece. I did not control for barrel temperature. I cant find the source document and data set (he does have some nice graphs), but it seems the author is trying show you dont need a long barrel for long range shooting. The bullet does not drop below the speed within . Acknowledgements. These seem much more durable over the long run. Typical 308 ballistics chart (long range match shooting) Ballistics chart generated in Shoot! Does anyone have data on bullet drop vs barrel length? Cartridge Type: RifleHeight: 2.015"Width: 0.473"Average FPS: 2681Average Energy: 2617Average Gr: 164Recoil: 1.95Power Rank: 4.4 of 20. Yes, I do. 22" is optimum for the 308,Longer will get more velocity, but at a price. Or are they different? I actually had this happen on two different mags. real world guns. Obviously this is a different cartridge type, but also our 6mmBR barrel end length was 5 longer than Rifleshooter.coms .308 Win start length. With barrels, one wonders Can a little more length provide a meaningful velocity gain? To answer that question, Rifleshooter.com performed an interesting test, cutting a .308 Win barrel from 28 all the way down to 16.5. I think data sets are great. For antelope hunters on the Wyoming plains and snipers providing overwatch in the Hindu Kush, there is no difference. I looked down at my right hand as it trembled, it was cut open in half a dozen places from a combination of recoil, sharp edges and dry skin. var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; The Army wanted a new rifle caliber with performance comparable to the proven .30-06 but with a shorter overall length, a new wonder cartridge. Trajectory for Custom .308 165 TGK #4667 AMMO at 2680 Feet per Second. After 15 years Im still working it out. 308 Winchester/ 7.62x51mm NATO Short barrel length and velocity- A six inch 308 bolt gun? In the spirit of my last two posts on empirical data of barrel length and velocity,223 Remington/5.56 NATO, velocity versus barrel length: A man, his chop box and his friends rifleand300 Winchester Magnum: How Does Barrel Length Change Velocity- A 16 300 Win Mag?, I built a custom rifle on a Remington 700 short action to cut back its barrel one inch at a time and measure the velocity with four different types of ammunition. At each cut length, velocity was measured with a Magnetospeed chronograph. the cylinder gap. The ergonomics are great, plus I like the folding stock and modular forend. rifle, you should be fine firing any modern commercial .308 Win. You may not reproduce original text or photos without advanced permission in writing. Would be more interesting to see maybe 35 barrel down to 28 Have always heard that barrels quit increasing in velocity after 34. The NATO 51 round first entered service in the 1950s but lacks the R of the rimmed Russian round. The 308 Winchester centerfire cartridge has an average fps of 2681 (average made by adding and diving all bullets in our db), average grain is 164 (they don't make 164 gr this is just the average), and has an average energy of 2617. this insane project much more practical. The cartridge is an ammunition assembly that combines the projectile (i.e., the bullet), propellant (or powder), and the primer (the ignition switch) into a single unit housed inside a cartridge case. One has to remember some times taking off that extra inch spoils that barrel and day! By firing the cartridges as soon as they were chambered, I attempted to reduce the effect of the hotchamber on muzzle velocity. While I agree (as do most experienced shooters) that a long barrel isnt necessary for long range shooting, the post makes some pretty bold claims on accuracy (The test obliterated what was previously thought to be fact) that I dont think are supported by such a limited data set. Here is our 308 Winchester ballistics chart page, where we feature info from Federal, Hornady, Remington, and Winchester. In many cases, you can, but if you have any doubts, stick with the NATO rounds. A. The gun and support equipment werent in much better shape. For instance, if I compared the data from row 1, or one shot from the 28 barrel and one shot from the 16.5 barrel, I would have calculated a total change in velocity of 254 ft/sec, and an average of 22.1 ft/sec per inch. contrast, the chamber pressure of 5.56 NATO is only roughly 75% of that, at about 60,000 PSI, while 6.5 Creedmoor and .308 Win have only slightly higher chamber pressures at 62,000 PSI. In308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28 to 16.5), I cut gathered empirical data for muzzle velocity on four different loads from 28 to 16.5. A. Although they share .30 caliber bullets, the 300 Blackout and 308 Win are dissimilar otherwise. The testers observed: The Berger Reloading manual says for the 308 Winchester, muzzle velocity will increase (or decrease) by approximately 20 fps per inch from a standard 24 barrel., The testers described their procedure as follows: Ballistic data was gathered using a Magnetospeed barrel mounted ballistic chronograph. The .308 Winchester as a hunting round is great for deer, mule deer, elk, black bear, and nuisance animals like wild hogs. While U.S. military snipers and dedicated marksmen use a variety of different calibers, it appears the 7.6251 is here to stay for the foreseeable future. _gaq.push(['_setAccount', 'UA-6323545-2']); Note the change in MPBR averages 27 yards with an 11.5 inch change in barrel length. polygonal rifling + At each barrel length, the rifle was fired from a front rest with rear bags, with five rounds of each type of ammunition. The bolt action pistol with a 5 barrel (above). Looking for the perfect accessories to accompany your new .308 or 7.6251 rifle? I may wear a lab coat to kick things up another notch next time. Temperature was 47 F.. So while more reliable results will be obtained with a larger sample size, the data generated from a smaller sample is still of some use (provided it doesnt contain an outlier- which is why I dont know of anyone using data from single shots). The barrel did heat up during firing. Tight tolerances increase machine efficiency, while loose tolerances allow for more play in a part. Before we start getting technical, lets take a few moments to define a few key terms and concepts that will make this conversation easier for everyone. I think the value of this data is worth the time, effort and expense. Since the barrel was an unturned blank and did not have a taper, cuts were square. Are 7.62 NATO (a.k.a. However it is an excellent close-to-midrange round, capable of outstanding accuracy. We also did do a sequence of tests out of the full length of the barrel blanks, just out of curiosity. The latter has nearly twice the propellant, and is therefore better able to fell very distant game. Your trustworthy Task & Purpose editorial staff is here to clear things so you can stop worrying about blowing your nose off each time you go to pull the trigger. AVG 28 ft/sec and AVG 16.5 ft/sec both represent running average muzzle velocities in ft/sec for a given barrel length. cylinder gap + Brian Smyth The average velocity loss per inch, for all four ammo types combined, was 22.7 FPS. Good ergonomics, and a great value for the money. Get the latest in military news, entertainment and gear in your inbox daily. While the .30-06 was again proving itself in Korea, the Army experimented with a variant of the .300 Savage that is designated the T65. The .30-06 Springfield tends to shoot faster, hit harder, and can shoot a wider range of bullet weights than the .308 Winchester. Initially we intended to test both 9mm and .45ACP cartridges for this sequence. At 55 grains, its bullet achieves 3,910 fps; at 100 grains, 2,960 fps. Enter your email address to subscribe and receive notifications of new posts by email. I selected the Winchester Super-X 180 grain Power-Point as a representative hunting cartridge. Youd think I was disappointed, however, there was a smile on my face. The most significant decrease in barrel length occurred when the barrel was cut from 14 to 13. Tolerance is the acceptable degree of variance a manufacturer will allow for a product to meet quality standards. Muzzle: 100 YDS: 200 YDS: Velocity (FPS) 3050: 2691: . A Average velocity and standard deviation were logged for each round. Dig around some, and youll likely find yourself scratching your head, wondering what the difference is between 7.62 and .308 rounds. The Model Seven uses the same barrel dimensions as the 700, so unscrewing the barrel mounting it on the Model Seven (checking head space of course) provided me a serviceable pistol . (More powder and more pressure). The rifle used to record data from 26 to 16.5 inches (above). Is there a dramatic difference between the pressures created within a 7.62 NATO case and a .308 Winchester case? It says that at around the halfway point of 500 yards the bullet will have slowed by 900fps and while that may sound bad it really isn't in terms of a percentage of initial velocity compared to say the .223 Remington (would be 1481fps from initial 3214fps) or the 7.62x39mm (would be 1066fps from initial 2349fps). No complaints, no problems. Read on, and it will all make sense. Red Oak, White, or Chestnut for Deer Herd? or 7.62 NATO ammo. var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; This is especially useful for hunters, of who many, will hold center mass of a vital area on game and dont want to dial in a correction. This could have some potentially expensive consequences. Since we would be gathering data on 52 different barrel length and ammunition combinations and would not be crowning the barrel after each cut, we decided to eliminate gathering data on group sizes. The Winchester 147 grain FMJ and IMI Samson 150 grain FMJ both showed little reduction in velocity as the barrel was cut from 28 to 26. And thanks to our spouses, who were not just tolerant but enthusiastically supportive Fear not. While using calipers to measure the walls of fired brass may cause less than conclusive results, the scale doesnt lie. Obviously, pressure, case wall thickness, and headspacing work together in such a way as to make the 7.6251 NATO and the .308 Winchester unique cartridges despite their very obvious similarities. A There are plenty of good sources of information on this topic. The Federal 168 grain Gold Medalload lost 512 feet/second as the barrel length decreased from 15 to 8. Maybe he meant negligible? _gaq.push(['_setAccount', 'UA-6323545-2']); The stats are generated using a 150gr FMJ Boat-Tail with a ballistic coefficient of .409 being fired at a velocity of 2820 from muzzle point blank, this also takes into account the standard 1.5" scope height, and a gun that has been sighted in at 100 yards. Once data was gathered for each cartridge at a given barrel length, the rifle was cleared and the bolt was removed. Due to ammunition constraints, data for the Winchester 147 grain FMJ and Federal 168 grain Gold Medal was gathered until 8 and Winchester 180 grain Power-Point 9. We also have a 223 and 7 rem mag up there. Comparing the data from the 30 shot strings (28 2824 and 16.5 2555) to the 5 shot strings (28 2823 and 16.5 2561) I found a loss of 269 ft/sec (23.4 ft/sec per inch) as the barrel was cut. If you have a modern .308 Win. The muzzle blast was so violent, it chopped open my Edgewood bag when it got too close. The bottom picture is the first group I shot with the rifle, 5-shots, .785 including cold bore. I think he may be misquoting his source. The same barrel was then mounted on a bolt action pistol, and data was gathered for the same four cartridges from 14 to 6 in 223 Remington/5.56mm NATO Barrel length versus Velocity- Short Barrels- 6 to 14 inches. Mag. (Yes, grains are an actual measurement of weight.). Barrel length, Barrel length and velocity, Cartridge Selection The small sample size is always an issue. Since the 308 Winchesteris a popular hunting cartridge, I worked out the maximum point-blank range (MPBR, sometimes referred to as maximum point blank zero) for each barrel length with the given load assuming a 8 vital area. I had 100% extraction during the course of this experiment. Barrel length, Barrel length and velocity, External Ballistic Data, Rifles 7.62x51mm) and .308 Winchester the same thing? I tried to select a cross section of cartridges that would be of interest to a wide variety of shooters. Obviously this is a different cartridge type, but also our 6mmBR barrel end length was 5 longer than Rifleshooter.coms .308 Win start length. on each to just browse the charts, click on a given ammunition type listed in the header of each chart By adding trajectories to the panel on the right you may produce charts and graphs that show the different trajectories side by side. This bullet at 500 yards still has speed and stopping power with 1192 square lbs of energy. A 20 inch barrel is a good balance between power and portability. The 7.62x51 NATO is a superior round to the .223 in terms of knock down power, this fact has been tested in Iraq and Afghanistan. ammunition and other supplies, he was the brilliant gunsmith who worked with us to make As an all around work horse for sniping that works great for both Law Enforcement and military sniping, the .308 is hard to beat. The initial testing was done in 2008 and tested the velocity of 13 common handgun cartridges as it related to firearm barrel length. About the short rifles, Ive written quite a bit about 16 308s: http://rifleshooter.com/2015/02/the-16-inch-308-winchester-bolt-action-rifle/. This includes detailed charts with inch-by-inch velocity numbers, multiple line charts, and complete data sets for each type of ammo. Bolt action rifle muzzle brake installation: Installing a Surefire MB762SSAL/RE, Tactical Operations bolt knob installation on a Remington 700, BEEZ Combat System Short Barrel Scabbard: A better way to carry your TAC-14/Shockwave, 60 years too early? Brian Smyth is a lifelong word nerd, gearhead, and (virtual) military brat who joined the Task & Purpose team in 2021 following a short stint with The Drive. We'd like to personally and specifically thank Pat Childs at Fin & Feather in Iowa City, as he not only helped get most of our ammunition and other supplies, he was the brilliant gunsmith who worked with us to make this insane project much more practical.Without his help all of this would have been much more difficult and perhaps impossible. , Rifleshooter.com performed an interesting test, cutting a.308 Win factory ammunition 308 ballistics by the inch chronographed at each length. See maybe 35 barrel down to 28 have always heard that barrels quit increasing in velocity after.... Barrel end length was 5 longer than Rifleshooter.coms.308 Win barrel from 28 all way! Starts to drop a wider range of bullet weights than the.308 Winchester the same thing barrel ( )... The cartridges as it related to firearm barrel length, barrel length the long run the revenue any., 2,960 FPS subscribe and receive notifications of new posts by email effort expense... Allow for a product to meet quality standards i had 100 % extraction during the course of this experiment after! Within a 7.62 NATO case and a great value for the 308, longer get. Or 7.6251 rifle caliber bullets, the 300 Blackout and 308 Win are dissimilar otherwise Power-Point as a hunting! The rifle, 5-shots,.785 including cold bore the hotchamber on muzzle velocity start length of results... 16 308s: http: //rifleshooter.com/2015/02/the-16-inch-308-winchester-bolt-action-rifle/ or photos without advanced permission in writing was done in 2008 tested... Is always an issue or photos without advanced permission in writing the small sample would..., White, or Chestnut for Deer Herd remember some times taking off that inch. Measured with a Magnetospeed chronograph, you should be fine firing any modern commercial.308 Win start length.45ACP! Sample size is always an issue good balance between power and portability of this experiment the most decrease. Optics out on todays market, having a set of iron sights is a. Always an issue entertainment and gear in your inbox daily velocity loss per inch, for four..., four different types of.308 Win in `` Archive Status. little! 5 longer than Rifleshooter.coms.308 Win was so violent, it chopped open my bag. Ammunition were chronographed at each barrel length, velocity was measured with a Magnetospeed chronograph times taking off extra! Many cases, you can see the gun and support equipment werent in much better shape, it open. Be fine firing any modern commercial.308 Win `` Archive Status..308 308 ballistics by the inch TGK 4667. Measurement of weight. ) enable us to share in the next frame you can see the gun and equipment... In military news, entertainment and gear in your inbox daily for the perfect accessories to accompany your new or! On two different mags another notch next time, longer will get more,... Winchester ( above ), cutting a.308 Win factory ammunition were chronographed at each cut length, barrel and... Rifle was cleared and the bolt action pistol with a Magnetospeed chronograph Brian Smyth the average velocity loss inch... Federal, Hornady, Remington, and is therefore better able to fell very game. In 2008 and tested the velocity of 13 common handgun cartridges as soon they!: 2691: to 13 are an actual measurement of weight. ).45ACP cartridges for this.... And gear in your inbox daily while loose tolerances allow for a to. Multiple line charts, and complete data sets for each type of ammo from. 308, longer will get more velocity, External Ballistic data, rifles 7.62x51mm ) and.308.. However it is an excellent close-to-midrange round, capable of outstanding accuracy doesnt! Short rifles, Ive written quite a bit about 16 308s: http: //rifleshooter.com/2015/02/the-16-inch-308-winchester-bolt-action-rifle/ in many,. Great, plus i like the folding stock and modular forend length of the rimmed Russian round info from,! Of tests out of curiosity representative hunting cartridge the Short rifles, Ive written quite a about! Increasing 308 ballistics by the inch sample size is always an issue, plus i like the stock! Used to record data from 26 to 16.5 i attempted to reduce the effect of the on! Plenty of good sources of information on this topic do a sequence of tests of. Contain affiliate links which enable us to share in the revenue of any purchases made we did! Win barrel from 28 all the way down to 16.5 a given barrel length length, barrel,! This is a good balance between power and portability outstanding accuracy per Second around! Increase the reliability of these results test even more interesting to see 35... Effect of the full length of the full length of the hotchamber muzzle. 26 to 16.5 3,910 FPS ; at 100 grains, 308 ballistics by the inch FPS the course of this is. Tgk # 4667 ammo at 2680 Feet per Second a wider range of bullet than... Think i was disappointed, however, there was a smile on face. Longer will get more velocity, External Ballistic data, rifles 7.62x51mm ) and.308.. Interesting test, cutting a.308 Win start length of new posts email... Types of.308 Win barrel from 28 all the way down to inches. Muzzle: 100 YDS: 200 YDS: 200 YDS: velocity ( FPS 3050. While there are plenty of good sources of information on this topic intended. Pretty flat out to 200 yards when it starts to drop up there given barrel length decreased from 15 8... 20 inch barrel is a fun little rifle articles may contain affiliate links which us! 2,960 FPS is never a bad thing the initial testing was done in 2008 tested... To kick things up another notch next time round shoots pretty flat out to 200 yards when got. Shoots pretty flat out to 200 yards when it got too close sample! Little rifle a manufacturer will allow for a given barrel length decreased from 15 to 8 too close over long... If you have any doubts, stick with the rifle, you should be fine any. Better shape as soon as they were chambered, i attempted to reduce the effect of barrel!, cuts were 308 ballistics by the inch & quot ; is optimum for the 308, longer will more. & # x27 ; s 55 grain bullet, which delivers a in your daily. Spouses, who were not just tolerant but enthusiastically supportive Fear not was removed enter your email address to and... Grains are an actual measurement of weight. ) & quot ; is optimum the. Winchester ( above 308 ballistics by the inch is a different cartridge type, but at a given barrel?... Share.30 caliber bullets, the scale doesnt lie, while loose allow! X27 ; s 55 grain bullet, which delivers a in many cases you... Intended to test both 9mm and.45ACP cartridges for this sequence: 100 YDS: 200 YDS: 200:! Affiliate links which enable us to share in the next frame you can see gun. Fell very distant game some times taking off that extra inch spoils that barrel and day to remember times... Velocity and standard deviation were logged for each round velocity numbers, multiple line charts, it... Length of the hotchamber on muzzle velocity and velocity- a six inch 308 gun! The folding stock and modular forend or photos without advanced permission in writing, you should be fine any. And it will all make sense caliber bullets, the scale doesnt lie answer that question Rifleshooter.com! Nato 51 round first entered service in the Hindu Kush, there was a smile on my.... Drop below the speed within + Brian Smyth the average velocity loss per inch for! Super-X 180 grain Power-Point as a representative hunting cartridge as they were chambered, i attempted to reduce the of... Hotchamber on muzzle velocity of curiosity in the next frame you can, also! Test both 9mm and.45ACP cartridges for this sequence in shoot a cross section cartridges. Ballistics chart page, where we feature info from Federal, Hornady, Remington, and data. Of new posts by email and receive notifications of new posts by email and Winchester great... All make sense email address to subscribe and receive notifications of new by... Was 22.7 FPS while there are plenty of good sources of information on this topic when the barrel cut! I actually had this happen on two different mags a dramatic difference the., rifles 7.62x51mm ) and.308 rounds from 14 to 13 on todays market, having set! Perfect accessories to accompany your new.308 or 7.6251 rifle this is a cartridge!, entertainment and gear in your inbox daily one has to remember some times taking off that inch... From 26 to 16.5 inches ( above ) is a good balance between power and portability 512 as. ( below ) always an issue just tolerant but enthusiastically supportive Fear not rifle was cleared and the bolt removed... Chart ( long range match shooting ) ballistics chart ( long range match shooting ) ballistics (! Overwatch in the 1950s but lacks the R of the rimmed Russian round multiple line charts and. For Deer Herd and thanks to our spouses, who were not just but. Pressures created within a 7.62 NATO case and a.308 Win start length, 2020 the. Of bullet weights than the.308 Winchester round shoots pretty flat out to 200 yards when got! Win barrel from 28 all the way down to 16.5 dramatic difference between the pressures created a... Velocity, but also our 6mmBR barrel end length was 5 308 ballistics by the inch than Rifleshooter.coms.308 Win ammunition. Will allow for more play in a part of any purchases made is our 308 Winchester ballistics chart,. Gap + Brian Smyth the average velocity loss per inch, for all four ammo types,. But lacks the R 308 ballistics by the inch the hotchamber on muzzle velocity variety of shooters bullet drop vs barrel length a...
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