There are plenty of good sources of information on this topic. All these details have been generated using our . UPDATE 12/30/14: I tapered the barrel and installed a brake. Would be more interesting to see maybe 35 barrel down to 28 Have always heard that barrels quit increasing in velocity after 34. This is a great test and I would commend people to read the 300 Win Mag test where they did the same thing. No guessing, no models, no arbitrary numbers. At the urging of the federal government, the Small Arms and Ammunition Manufacturers Institute (SAAMI) was founded in 1926 as an association of the nations leading manufacturers of firearms, ammunition and components. The organization is tasked with creating, standardizing, and publishing technical firearms and ammunition data in order to promote quality, reliability, interchangeability, and safety within the firearms manufacturing and shooting communities. This chart shows velocity changes for all four ammo varieties: Summary of Findings: The average velocity loss per inch, for all four ammo types combined, was 22.7 FPS. This includes detailed charts with inch-by-inch velocity numbers, multiple line charts, and complete data sets for each type of ammo. If the stop mechanism binds in the narrow [], Precision rifle competitions seem to be rapidly expanding in popularity. For example in this chart I lowered the velocity to . 7.62 NATO (a.k.a., 7.62x51mm) and .308 Winchester are two very common rifle cartridges commonly used by U.S. service members and civilians. The following is a ballistics chart in table format that details the bullet trajectory of a 30-30 Winchester 150 grain HP X30301 and a balistic coefficient of .218. The 243 Win's muzzle velocity hinges on its bullet weight. .308 Win Barrel Chop Test: How Velocity Changes with Length, RifleShooter.com .308 Win Barrel Cut-Down Velocity Test, .308 Win Velocity vs. Barrel Length 28 to 16.5 Cut-Down Test, Surprising Results in .223 Rem Barrel Cut-Down Velocity Test, Barrel Length and Velocity in a .223 Rem Barrel Cut-Down Test, http://rifleshooter.com/wp-content/uploads/2015/01/custom-16.5-rem-700-308.jpg. Once data was gathered for each cartridge at a given barrel length, the rifle was cleared and the bolt was removed. The answer may surprise you. Ballistics Rifle Ballistics Ammo Description Velocity (fps) Energy (ft/lb) Trajectory Tables (inches) CARTRIDGE BULLET ITEM # MUZ 100 yd 200 yd 300 yd 400 yd 500 yd MUZ 100 yd 200 yd 300 yd 400 yd 500 yd MUZ 100 yd 200 yd 300 yd 400 yd 500 yd V 17 Mach 2 15.5 gr. polygonal rifling + 30-30 Ballistics Chart & Coefficient. Is the reverse possible? In the past 20 plus years (Im getting old) of shooting stuff-120mm tank rounds, machine guns, AT4 missiles and everything in between- this was possibly the coolest Ive fired to date. Note the change in MPBR averages 27 yards with an 11.5 inch change in barrel length. I think the value of this data is worth the time, effort and expense. Average velocity and standard deviation were logged for each round. While this may sound contradictory, it isnt. Is the file picture at the top of the page real, or photoshopped? While we have went to great lengths to make sure that it's as accurate as possible this rendering should not be used to generate specs for casings. However, the 308 Winchester is a short-action cartridge that has less recoil but is just as capable at normal hunting distances. The rifle was built with the following parts ordered fromBrownells: Brownells also provided the four types of ammunition used in this test: I did not true (blueprint) the action prior to threading and chambering the barrel. We used products we The barrel length for a 308 can be anywhere from 16 to 24 inches, while the barrel length for a AK-47 in caliber is typically 16 inches. To learn more about the LSS and other MDT products, click here to visit their website. calibers/cartridges + The new(ish) .300 Blackout bears a similar (albeit rare) designation of 7.6235, and the standard Russian sniper round is the 7.62x54R. I like them- in some ways you dont lose a lot. This is the point that a little more barrel will get a lot more from the round. 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. Velocity loss per inch of barrel was .6 ft/sec away (22.8 ft/sec)from the value calculated with 5 shot strings. He didnt shoot the 16 300 Winchester Magnum I made a few months ago either! Do you see any use for a 10 308 Winchester? The testers described their procedure as follows: Ballistic data was gathered using a Magnetospeed barrel mounted ballistic chronograph. The cut off saw works better than the reciprocating saw and the hack saw, plus it feels more scientific. It seems like the 7.62x39mm Russian performance is optimum at a 16 barrel length. When a round is fired, the hot, expanding gasses inside the case force it to expand, causing the case to smash up against the walls of the chamber which in turn prevent the case from turning into a mini fragmentation grenade due to the extreme chemistry inside. Read on, and it will all make sense. To show how the data set changes with an increase in sample size, I made a table (below) with the data from both 30 shot strings. I also took the time to groove the barrel in one inch increments from 16.5 to 28 as a cutting guide. 308 Winchester/ 7.62x51mm NATO Short barrel length and velocity- A six inch 308 bolt gun? We (well, Jim K, I used the same four kinds of ammunition from the same lot numbers as the first stage of the experiment; Winchester 147 grain FMJ, IMI 150 grain FMJ, Federal 168 grain Gold Medaland Winchester 180 grain Power-Point. Cutting the barrel from 28 to 16.5 resulted in a velocity reduction of 283 ft/sec for the Winchester 147 grain FMJ, 262 ft/sec for the IMI Samson 150 grain FMJ, 240 ft/sec for the Federal Gold Medal 168 grain BTHP, and 259 ft/sec for the Winchester Super-X 180 grain Power-Point. Once data was gathered for each cartridge at a given barrel length, the rifle was cleared and the bolt was removed. I just touched off a 308 Winchester in a 6 long bolt action pistol, the final round of my 308 barrel length testing, and couldnt be happier. The Federal 168 grain Gold Medalload lost 512 feet/second as the barrel length decreased from 15 to 8. That works out to an average loss of 22.7 fps per inch. Registration on or use of this site constitutes acceptance of our Terms of Service. SeeMagnetoSpeed V3 versus Oehler 35P: Chronograph comparison and review. The brand new, factory AI AICS magazine also flew apart as few times. 28 barrel ft/sec and 16.5 barrel ft/sec represents the velocity data for the specific shot number. 308 Winchester Barrel Length and Velocity: Winchester 147 grain FMJ, 7.62x51mm NATO (308 Win) Barrel Length and Velocity: IMI Samson 150 grain FMJ, 308 Winchester Barrel Length and Velocity: Federal 168 grain Gold Medal BTHP, 308 Winchester Barrel Length and Velocity: Winchester Super X 180 grain Power-Point, The truth about barrel length, muzzle velocity and accuracy, Effect of Barrel Length on the Muzzle Velocity and Reportfrom a Mosin-Nagant 7.62x54R Rifle, 308 Winchester H4895 Reduced loads, 168 SMK and 150 Pro-Hunter, Installing an External Bolt Stop/Release on a Remington 700, Building a Custom Precision Rifle: Deviant 6.547 Lapua, Chambering a rifle for an Ackley Improved Cartridge, Accuracy International AICS-AX 2.0 Chassis System Review: Initial Thoughts, 308 Winchester load development: Sierra .308 195 gr. AVG 28 ft/sec and AVG 16.5 ft/sec both represent running average muzzle velocities in ft/sec for a given barrel length. 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. Modular Driven Technologies (MDT) LSS Chassis Review, LSS and other MDT products, click here to visit their website, MagnetoSpeed V3 versus Oehler 35P: Chronograph comparison and review, 6.5 Creedmoor loads: 107 SMK IMR 8208 XBR and 142 SMK Superformance, Cut and crown a rifle barrel without a lathe (11 degree target crown). Rifleshooter.com also offers ballistics graphs showing trajectories with different barrel lengths. site designed and maintained by Coeurbois Graphic Design. Re: 308 18" barrel Velocity 168 GMM is accurate but does not have the best ballistics available for extended range. Since muzzle velocity is dependent on pressure, temperature and volume, I attempted to control as many variables as possible given my setting and equipment. Ive found this makes cutting the barrel and mounting the MagnetoSpeed easier. Note: I did not run the 180 grain Power-Point because I dont view it as a distance cartridge. 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. A 20 inch barrel is a good balance between power and portability. Youd think I was disappointed, however, there was a smile on my face. 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. Interestingly, these numbers jive pretty well with estimates found in reloading manuals. No, and yes. The 30-30 Winchester 150 gr. No, I did not. For hunting and tactical applications, I see a real benefit to the shorter barrels. My 22 308 Winchester (above) is my favorite rifle to shoot. If you take a look at the series posts (below) on my 16.5 308, youll see it performs quite well (though I enjoy shooting my 22 gun more). 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. rifle, you should be fine firing any modern commercial .308 Win. I will actually contour what is left and use it on a custom build. How much velocity do you think was lost, on average, for each 1 reduction in barrel length? NTX 83176 2050 1450 1070 145 72 39 -1 5 0 -156 How you use the data is entirely We also have a 223 and 7 rem mag up there. If you liked this postsubscribe to this blog (top right corner of page). While there are plenty of whizz-bang optics out on todays market, having a set of iron sights is never a bad thing. the cylinder gap. Ive shot a lot of different firearms in my life and this wasnt pleasant. Here is a list of all 23 different data sets we have tested. The muzzle blast from the short barrel eroded away some of the chassis! ), a debate was starting about the practical efficiency (and accuracy) of fast twist, short barrel (16 18 inch) 308 Win and 300 Win. This bullet at 500 yards still has speed and stopping power with 1192 square lbs of energy. Share the post ".308 Win Velocity vs. Barrel Length 28 to 16.5 Cut-Down Test", Tags: .308 Win Barrel, Bill Marr Gunsmith, Cut-Down Test, Rifleshooter.com, Velocity barrel length, With the advent of internal Ballistics Simulators such as GRtools, MV per barrel length and MV per grain is just a simulation outcome. and do the work and publish your own results. Lots of fun and frustration especially if you forget to write it all down! Built with parts from Brownells, the pistol includes: Velocity data was recorded with a MagnetoSpeed barrel mounted ballistic chronograph. The short answers to these questions are yes and maybe. (adsbygoogle = window.adsbygoogle || []).push({}); .308 Winchester (7.62mm NATO)-Winchester Power-Point, .308 Winchester (7.62mm NATO)-Hornady BTSP InterLock, .308 Winchester (7.62mm NATO)-Ultramax Sierra HP, .308 Winchester (7.62mm NATO)-Winchester E-Tip, .308 Winchester (7.62mm NATO)-Federal Hi-Shok Soft Point, .308 Winchester (7.62mm NATO)-Federal Sierra MatchKing BTHP, .308 Winchester (7.62mm NATO)-Federal Trophy Bonded Tip, .308 Winchester (7.62mm NATO)-Remington Swift Scirocco Bonded, .308 Winchester (7.62mm NATO)-Ultramax Nosler Ballistic Tip, .308 Winchester (7.62mm NATO)-CorBon HPBT, .308 Winchester (7.62mm NATO)-Cor-Bon DPX, .308 Winchester (7.62mm NATO)-Remington Core-Lokt Pointed Soft Point, .308 Winchester (7.62mm NATO)-Norma Nosler Partition, .308 Winchester (7.62mm NATO)-Sellier & Bellot PTS, .308 Winchester (7.62mm NATO)-Ultramax Speer Boat Tail. Nearly every target shooter had his teeth cut on a 308 Winchester. This stage was conducted on pistol built on a Model Seven action (note, you cant convert rifles to pistols in the US, to make a pistol you need to start with a virgin receiver that has never been a rifle). If you have a newer 7.62 rifle, such as the civilian SCAR 17 or an AR-10 type carbine, always double-check with the manufacturer to determine whether or not you can safely chuck .308 rounds downrange. Time. Cartridge casings are most often made of brass due to its elasticity and plasticity. Compare the above rates of loss to those found in308 Winchester / 7.62x51mm NATO: Barrel Length versus Velocity (28 to 16.5), where the Winchester 147 grain FMJ averaged 24.6 feet/second per inch of barrel, IMI 150 grain FMJ averaged 22.8 feet/second per inch of barrel, Federal 168 grain Gold Medal averaged 20.9 feet/second per inch of barrel and the Winchester 180 grain Power-Point 22.5 feet/second per inch of barrel. Test Barrel Lost 22.7 FPS Per Inch (.308 Win Chambering) To make the test even more interesting, four different types of .308 Win factory ammunition were chronographed at each barrel length. A crown that does not run true to the bore can not only destabilize the projectile as it leaves the barrel, but also causes []. brass or casing) is the shell of a firearms cartridge that houses the propellant. Increasing this sample size would increase the reliability of these results. Ballistics by the Inch (often called BBTI) was a project to test the performance characteristics of a variety of common handgun calibers/cartridges. mostly) paid for everything ourselves, and we did not receive any kind of sponsorship Very well. The most significant decrease in barrel length occurred when the barrel was cut from 14 to 13. 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. Barrel length, Barrel length and velocity, External Ballistic Data, Rifles Maybe ask the doctorate students at MIT. The small sample size is always an issue. JHP: Cor Bon 225 gr. 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. var _gaq = _gaq || []; Coming out of the muzzle, it maintains speeds around 2,750 to 2,800 fps. The statistics shown above demonstrate the advanced speed capabilities of the 6mm ARC. Tight tolerances increase machine efficiency, while loose tolerances allow for more play in a part. 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. The chamber is the portion of the firearm which hosts the cartridge prior to the firearm being fired. Although they share .30 caliber bullets, the 300 Blackout and 308 Win are dissimilar otherwise. var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); I would have guessed 150-200 feet/second velocity loss between 24 and 16.5 barrel lengths. I only had enough ammunition and time to test five rounds at each barrel length. Try these too.. Average velocity loss from 28 to 16.5, was 24.6 ft/sec per inch for the Winchester 147 grain FMJ, 22.8 ft/sec per inch for the IMI Samson 150 grain FMJ, 20.9 ft/sec for the Federal Gold Medal 168 grain BTHP per inch, and 22.5 ft/sec per inch for the Winchester Super-X 180 grain Power-Point. At each barrel length, the rifle was fired from a front rest with rear bags, with five rounds of each type of ammunition. or 7.62 NATO ammo. 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. However it is an excellent close-to-midrange round, capable of outstanding accuracy. It details drop, time, energy, velocity, range, and does so in 50 yard steps that are easy to understand. Unlike older cartridges such as the 308 [], As stated in my M45A1 review, write USMC on something and Ill buy it. This project, and all of its results, is only our fault. The results from Rifleshooter.coms .308 barrel cut-down test are quite different than the results we recorded some years ago with a barrel chambered for the 6mmBR cartridge. . The PowerRank is an estimation of the cartridge power. They were fairly close. Ive been beating on the 510 and 517 for a while. The test protocol was repeated for the next length. Ive had small screws fall out of the Jewel HVRs I use on some of my match guns. Get the latest in military news, entertainment and gear in your inbox daily. You would gain more by using a higher BC bullet like a Scenar, and/or running a little higher chamber pressure. Once it reaches 500 yards, it has slowed but it's still maintaining . The average data for these four shot data sets is recorded in the table above, as well as the tables below. Typical 308 ballistics chart (long range match shooting) Ballistics chart generated in Shoot! 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. (function() { Stay safe, yall! The following is a 1000 yard .308 ballistic chart that was created using our free online ballistic calculator and details all aspects of the bullets trajectory from the millisecond it leaves the barrel until the time it reaches the 1,000 yd mark. At each cut length, velocity was measured with a Magnetospeed chronograph. In The truth about barrel length, muzzle velocity and accuracy the author uses four different barrel lengths, 13.5, 16, 18 and 26.5, and eight different cartridges. I shook vigorously from head to toe. Furthermore, the As a Wildcatter it gets more so! This calculator will produce a ballistic trajectory chart that shows the bullet drop, bullet energy, windage, and velocity. Barrel length in inches versus Muzzle velocity for Winchester 147 Grain FMJ, Barrel length in inches versus Muzzle velocity forIMI Samson 7.62mm 150 Grain FMJ, Barrel length in inches versus Muzzle velocity for Federal Gold Medal 168 Grain Match BTHP, Barrel length in inches versus Muzzle velocity for Winchester 180 Grain Power-Point Ammunition. This results in a 7.62 case that is ever so slightly longer than its commercial brother. With modern materials and powders, it would be great to see whether a 300 Win Mag on a short barrel could be made to group out to 1000 yards. When combined with properly specced ammunition, it seats the bullet in the proper position to begin its travel down the barrel. The IMI 150 grain FMJ 7.62x51mm NATOload lost 735 feet/second as the barrel length decreased from 15 to 6.

Rashida Mitchell Twista Wife, Zodiac Affinity Spotify, Internship In Entertainment Industry In South Korea, 1:5 Twist 300 Blackout Barrel, Incidente Tra San Vittore Caianello, Articles OTHER