The 6.5mm calibers are popular today, mainly helped by the popular 6.5CM, almost obliterating the existence of other calibers...
In this article we offer you a comparative study of performances between the 6.5mm calibers: barrel life, exit speeds, drops, wind resistance, probability of impacts, ease of reloading, ... everything is there!
from left to right: 6.5 Grendel, 6.5x47L, 6.5 CM, 260 Rem, 6.5x55SE, 6.5-284 Norma, 6.5 PRC, 26 Nosler
The calibers we are going to compare in a few words:
- 6.5 Grendel: one of the smallest 6.5, initially produced to fit into AR-15 platforms, boosting the performance of the 5.56. It is found in some high-precision weapons ( 6mmbr forum link ) It is compared to a 6mm PPC, capable of incredible accuracy at short range, with almost indestructible barrels!
- 6.5X47L: A modern caliber developed by the Finnish firm Lapua, to face the 6mm BR on matches of 300-600 yards, it is recognized for its intrinsic precision to the caliber. One of the most seen 6.5 calibers in the world of PRS in the USA where 6mm dominate.
-6.5 Creedmoor: Do we still need to introduce this caliber? Introduced by Hornady in 2008, it shook the TLD world, and yet? It does not bring much difference on its cousins (6.5x47L and 260 Rem) from a performance point of view, on the other hand many manufacturers have jumped on the bandwagon (manufactured weapons and ammunition) which has allowed its wide distribution.
- 260 Rem: The neck down version of a 308Win with a 6.5mm projectile, it has long been a fashionable ammunition, today rare are the people launching into this caliber: Conversion of 308Win cases to 260 (advantage for some, disadvantages for others) the case is long, and prevents to sufficiently extract the heavy projectiles in 6.5mm if one wishes to feed to the magazine... We therefore lose capacity of the case... A cartridge which had its hour of glory, but this one has passed...
- 6.5 X 55 SE: The granny of comparison! Created in 1891, produced in 1894 and yet still relevant today! The most fired caliber in the Nordic countries (Finland / Sweden / Norway) the original pressure of the ammunition (3800 bars) prevents manufactured ammunition from being truly efficient, on the other hand any reloader will be able to load his ammunition at the same pressures as these cousins (4300 bars) and benefit from advantageous ballistics!
- 6.5-284 Norma: The king caliber of the F-CLASS F-OPEN 20 years ago, where it dominated all the matches, little by little fell into disuse, and for good reason... when a barrel reaches 1500 shots it is a real miracle! When you know that an F Class match is on average 60 shots... Plus the training, you need at least 2/3 tubes over a shooting season! Leading to significant costs and a lot of work on load developments. Today it has been replaced by its 7mm version (284 Win) in its standard version and in its improved 284 Shehane version. A caliber for those who want to have XXL performances and who do not worry about the future of the tube!
- 6.5 PRC: The new kid on the block! Introduced in 2018, it brings a very high level of performance for a 6.5mm in short action, the first magnum on the list, or rather short magnum! A very high-performance caliber, initially created for hunting, but gradually entering the world of TLD, it has the same issues as the 6.5-284... A high consumption of barrels, American F Class shooters having already created an alternative to this caliber in F CLASS (the 7mm-6.5PRC) a Neck Up version of the 6.5 PRC that accepts 7mm bullets (Eric Cortina shoots this caliber)
- 26 Nosler: You asked for a speed demon? Here it is! A 6.5mm with a case capacity of 93 gr of H2O! (In comparison, a 300 PRC has a case volume of 77 gr of H2O!) Capable of propelling the heaviest 6.5mm projectiles beyond 1050 m/s! A Laser! But an ultra consumer of barrel... Performance has a price!
Our first comparison: Dimensions, pressures, type of priming, availability of quality cases (LAPUA), existence of Small Rifle primed cases, Availability of manufactured ammunition:
Estimated life of the guns:
Small quickload analysis giving the maximum speed of these calibers with a BERGER 140gr Hybrid projectile.
For the 6.5X55 and 6.5-284 Norma calibers, we have voluntarily used pressures higher than the standard; we are not dealing with manufactured ammunition!
We have deliberately simulated in two barrel lengths, starting with the results of speed and probabilities of impacts on a 30x30 cm plate at distances ranging from 400 to 1000 meters in the case of a 24 inch barrel.
Hypothesis: Weapon capable of grouping in 1/2 MOA at 100 meters, wind +- 1m/s, SD ammunition: 3 m/s
The same case as before but this time simulated in a 30 inch barrel
We notice that the magnum calibers gain the most in probability of impact by going from a 24" to a 30"
Example at 800 meters in 6.5x47L gains 2.5% impact rate, when the 26 Nosler gains 4%.
My personal opinion:
The 6.5 Grendel is a possibility for those who stay in the 0-500 meter zone and have an extremely precise weapon, which does not cost much to shoot and with a barrel that will not wear out... Beyond that... It's complicated!
A trio is almost on equal terms in terms of performance (6.5x47L / 6.5 CM / 260 Rem)
The 260 Rem is outdated, very low resale value, I wouldn't try it!
6.5X47L easier to develop, but no manufactured ammunition (or very little only LAPUA) and a lower muzzle velocity of 20-30 m/s on the 6.5CM. The caliber you need for a picky reloader!
6.5 CM is the caliber for those who want to touch the world of 6.5mm without touching the world of reloading, or who are looking for a factory weapon.
6.5X55 SE : To be preferred on long barrel weapons, 28/30" mini with modern reloads, same operating cost of a 6.5CM when reloading at a few cents. Why not
6.5-284 Norma: Move along, the 6.5 PRC is in the place!
6.5 PRC: The caliber you need if you want 6.5 magnum performance without literally breaking the bank, availability of standard weapons and manufactured ammunition... Quality components... In short, a good 6.5 Magnum!
26 Nosler: A caliber for exceptional weapons, you want to make a laser beam weapon for hunting in the high mountains, at long distance, you are not going to fire hundreds of shots... It is an extraordinary caliber, be careful however with the sourcing of components (cases) which can be complex!
My 2 cents!