Reloading for a Chilean Mauser Converted to 7.62 NATO
In my experience reloading for another Ludwig Loewe Chilean Mauser, I found good accuracy and top velocities that duplicated some of the most accurate 7.62×51 NATO ammunition using IMR3031 for both 150 and 165 grain bullets. Using military brass, somewhere between 38 to 40 grains of IMR3031 under a 165 to 168 grain bullet, will duplicated the old Navy Match Load. A maximum of 42 grains of IMR3031 will duplicate 7.62×51 NATO trajectories with good accuracy, and that also happens to be close to where these rifles originally had their sights adjusted when they are re-arsensalized and the new 76.2 barrel installed. If the sights have not been altered in some way, the 165 grain load could be close to dead on at 25 yards.
To take full advantage of the long barrel, use 168 to 175 grain projectiles with modern ballistic coefficients. The military ball ammunition with the designation of M118 is designed for accuracy at long range. M80 ball ammunition uses a 150 grain bullet is intended for box fed automatic or semi automatic rifles for shorter ranges, usually less than 500 meters. M80 is in general, not as accurate as M118. For moderately long ranges out to 800 yards, and further if you can, M118 ball ammunition would be ideal in this rifle. M118 ball ammunition is made for hitting small targets at extended distances. I would not be surprised to chrongraph a 173 grain projectile at 2,700fps out of this rifle. And this would simply be outstanding. A reloader could install a 176 grain Hornady A-tip with a G1 B.C. of .564, and nearly duplicate the trajectory of 140 grain 6.5 Creedmor load out of a 22 or 24 inch barrel. Modern powders and bullets are changing the game for older rifles. Too bad they do not make a magic powder for aging hermits!
Unfortunately, I can not recommend any commercially produced ammuntion that offers soft point bullets. Hunting ammunition may only be available to those who can reload using soft point bullets. A reloader can remove the FMJ military bullet and install a soft point or polymer-tipped bullet of the same weight if the length of the bullet and the C.O.L., cartridge overall length remains the same. However, one should proceed as if they are working up a new load and reduce the powder charge by 10 percent and work up.
If reloading for this action with a carbine length barrel that yields lower velocities that produces at most 2300 to 2,400fps, I recommend expensive premium expanding bullets such as Nosler Ballistic Tips and Hornady GTX bullets design for the .30-30 that will still expand at velocities as low as 1,600fps. Yet ideally, for faster kills, velocity at impact should be no lower than 2,200fps as the effect of hydrostatic shock greatly diminishes thereafter. A softer bullet that expands quickly at velocities below 2,400fps help compensate for a lack of hydrostatic shock that be diminished inside of 100 yards. Bullet construction and other aspects of cartridge design is a much-misunderstood part of reloading. that becomes more of an issue at longer ranges when fired using lower pressure cartridges and through very short 18 inch carbine length barrels. The carbine has it’s place however, and is wonderfully handy. It would be a good home defense and woods rifle where ranges are particularly short.
Factory 7.62 NATO Ammuntion for Converted 7.62 NATO M95 Mausers
Use only genuine 7.62×51 NATO military ball ammuntion as produced by well-respected manufacturers such as Lake City Arsenal, and IMI. Do not use any factory ammunition with a designation for .308 Winchester. Stick with only the recommend 7.62 NATO ammunition. .308 Winchester will produce dangerously high pressures and likely ruin the action by setting the bolt back, and possibly rupture a case and leak high-pressure gasses into the face of the shooter.
The action of the Ludwig Loewe Chilean Mauser can indeed safely handle genuine 7.62 NATO ammunition, yet the buyer of this rifle needs to understand the difference in ammunition types, and only purchase only genuine military ball ammunition, and not commerical ammunition that is labeled as 7.62×51 NATO. I can only recommend this rifle if the buyer has a clear understanding of the different types of ammunition. If there is any question about what ammunition is appropriate for this rifle, then consult your local gunsmith.
Here are two excellent choices and examples of ammuntion for this rifle:
To reitierate and reinforce, the appropriate ammunition for this rifle is 7.62×51 NATO that is loaded to a considerably lower pressure, 46,000CUP, or 51,000psi versus .308 Winchester, 62,000psi, and uses a cartridge case that is significantly thicker and stronger at the base portion of the case, or case head. As I have reloaded for this and other antique rifles, I’ve concluded via experience with commercial ammunition, that some manufacturers have allowed their marketing departments too much artistic license in describing their ammunition that can be labeled incorrectly, or inadvertently confused with higher pressured .308 Winchester ammunition that is dangerously high for antique actions. And their ammunition is not necessarily held the strict standards and design parameters required to meet exacting specifications for genuine 7.62 NATO ammunition. The result is that over time, the distinction between the ammunition types has been blurred, and some shooters of this rifle became understandably confused.
7.62 NATO Ammo is Not the same as .308 Winchester
IHMO, this trend persisted because modern gas operated semi auto rifles are indeed strong enough to tolerate the higher pressures, whereas that the M14 that the cartridge was designed for, required that only specific powders and lower pressures be used to avoid damaging the mechanical parts, primarily the op rod that is heart of it’s gas operated action. The M14 is essentially a modified and improved M1 Garand. The Navy’s version of the M1 Grand was the first service rifle to used 7.62×51 NATO spec ammunition. All the powders used in this ammunition will not harm the M1 Grand that was the platform used to develop this ammunition. The op-rod could be damaged by the duration and intensity of peak pressures within the barrel that needed to occur before reaching the gas port at the end of the barrel, so as not to overdrive the operating rod (“op rod”) and bend it. The M1 Garand, and its relations, the M14 and the M1A — the civilian semi-automatic version of the M14, cannot tolerate an over-gassed system, a condition that is caused by the use of incorrect rifle powders, cartridge pressures, and bullet weights. Therefore 7.62×51 NATO cartridges are held to strict design specifications. Now you know that .308 Winchester is not the same as 7.62 NATO, and why “7.62 N” is stamped on the receiver of this Mauser.
And to further reiterate, we can see why modern military gas-operated rifles must only use an ammunition type that is specifically designed for these fine machines. Modern gas-operated rifles such as semi-auto LR308, or AR-10 pattern rifles, FN FALs, PTR91s, and other gas-operated semi-autos that use 7.62×51 NATO, do not necessarily have the same exact vulnerabilities as did the M14 (M1A), and M1 Garand, yet these others are designed to operate using this ammunition. They design to a standard that is 7.62 NATO ammunition sets, and for a reason. As 7.62 NATO is the ammunition that is part of an ammunition supply to most western countries’ armed forces, there is a massive amount of the ammunition type in existence that it essentially set the standard for armies of western civilization.
The FN FAL has a gas adjustment at the gas block, so that it can tolerate heavy 7.62 ball for machine guns and for 7.62 NATO that might be a bit stout for its action. These military rifles are not designed for .308 Winchester. If used, if not sooner, over time, the mechanisms of various gas-operated rifles, and their barrels can experience accelerated wear, or can become damaged at an accelerated rate, if the higher in pressure .308 Winchester ammunition is used in large or smaller quantitiy. Semi-automatic rifles are finely tuned machines comprised of levers and springs that once worn, or damaged by excessive force, becasue the system is ‘over gassed’, can eventually fail to operate as designed. Use only the highest quality 7.62 NATO ammunition you can find, and not ammo made in Turkey or Timbucktoo. Even though there exists a standard, you may never really know what you are going to get. Lake City ball is the best way to go. As discretion is the better part of valor, if you are unsure about these matters, take it to a gunsmith and let him determine the best ammunition for this rifle for you, then buy a lifetime supply of that. It’s like taking your car to a mechanic.
Ammunition for Antique Rifles in 6.5×55
“The 6.5×55 is a forgiving, well balanced cartridge and practically any medium-slow burning rifle powder will prove suitable. Among the powders tested that provided top accuracy for Nosler technicians were VARGET (with 100 grain bullets), AA-3100 (with 120 grain bullets), IMR 4350 (with 125 grain bullets), and RL-22 (with 140 grain bullets).
The Speer Reloading Manual No. 13 shows that their 120 grain spitzer bullet (BC .433) can be driven to a MV of 2650 fps with 45.0 grains of IMR 4831 powder, and 2886 fps with 49.0 grains of the same powder.
The Speer 140 grain spitzer (BC .496) can be driven to a MV of 2449 fps by 44.0 grains of RL22 powder, and 2671 fps by 48.0 grains of RL22.
Speer recommends the 120 grain bullet for antelope and the smaller deer, and the 140 grain bullet for large deer and black bear. The good old boys at Speer tested these loads in a Ruger M77 rifle with a 22″ barrel, and used Federal cases and CCI 200 primers.
The Hornady Handbook of Cartridge Reloading, Sixth Edition shows that their sleek 129 grain Spire Point and SST bullets can be driven to a MV of 2700 fps by all eight powders listed. Examples would be 42.4 grains of IMR 4350, 45.5 grains of H450, 42.1 grains of Win. 760, or 45.4 grains of RL-22. A typical starter load would be represented by 34.4 grains of RL-22 for a MV of 2300 fps. These loads used Hornady brass and Winchester WLR primers, and were chronographed in a Model 1896 Mauser with an 29″ barrel.
The fifth edition of the Nosler Reloading Guide lists loads for their excellent 125 grain Partition bullet in front of 41.5 grains of IMR 4350 powder at a MV of 2592 fps, and 45.5 grains of 4350 at a MV of 2910 fps. Norma cases and Remington 9 1/2 primers were fired in a 23″ barrel to develop these loads.
The Sierra Edition V data manual shows that 36.5 grains of RL-22 behind their 160 grain bullet is good for a MV of 2200 fps, while 40.5 grains of RL-22 can drive the same bullet to a MV of 2400 fps. Federal cases and Federal 210 primers along with a Model 96 Swedish Mauser rifle with a 29″ barrel was used to develop these loads.
The 6.5×55 is one of my very favorite hunting cartridges and very easy to reload. Almost any hunter/reloader who tries it is bound to be pleased.”
Everything Chuck Hawks said then is still true today, and it is hard to add more to his description, yet as decades have passed, more experience with this cartridge has caused reloaders to discover modern powders that are much less temperature sensitive, and we now have modern bullets to work that offer extreme high ballistic coefficients. These will further improved the Swedish Mauser’s legendary performance. The real 6.5 Swede fans call the 6.5 Creedmoor (6.5×48), the “6.5 Cost More”. The 6.5×55 is still king in Sweden. With the advent of 6.5CM came with it, a rush to develop the very best 6.5 bullets created in the history of mankind. Folks like me who are Swedish at heart will take the best projectiles that the 6.5CM crowd has to offer. Yet higher ballistic coefficient bullets are not all that we should be after to improve our game and rifle’s performance.
An Antique M96 Swedish Mauser Versus a Brand New 6.5 Creedmoor
In a cut down version of a table previously used is the proof that the old long barreled Swede is not long in the tooth. In a comparison, I used proven data for RL22 that delivers top accuracy at top velocities that exemplifies the most competitive loading that the old Swede can shoot to blow away the best examples that the 6.5CM can bring into the ring. This load is right near the maximum allowable pressures for an antique M96, that is at 46,000 CUP (Approximately 51,000 psi).
The craftsmanship that went into the early Mauser M93s, M95s, and M96s is top shelf, but the Swedish Government insisted that the Germans make the M96 with naturally occurring and superior Swedish steel alloy that contained nickel and other elements that differentiates the M96 from the other Mausers of that era. Swedish steel notwithstanding, the pressure limits are limits to be respected. The 29-inch M96 barrel compensates for the lack of pressure use to accelerate a 140 grain mass, where as the 6.5 Creedmoor uses modern high chamber pressures near 62,000 psi. Swedish Mauser barrels, antique or not, not only have superior metallurgy of that time, but because of the lower pressure cartridges, excellent armory maintenance, and use of non corrosive primers, the barrels in these rifles are some of the best in condition that can be found on antique.
My 1905-dated Model 1896 Mauser has a ‘zero’ bore that is essentially new in condition that I believe was made on the same production line that a 1898 M96 was put together on. It is sub MOA with H4350, using an inexpensive 140 grain hunting bullet. Some believe that Swedish Mauser barrels never completely wear out. They do, but only after an inordinate amount of rounds, perhaps after 10,000 rounds or more. Because of the very high pressures, and the almost over-bore caliber, the 6.5CM could be expected to lose its fine accuracy after only a few thousand rounds. Old Swedes just keep on a-goin’, round after round. With this fact in hand, embrace the long barrelled antique rifles if your aim is to put rounds down range at greater distances. Swedish Mausers will be in any serious rifle enthusiaist’s inventory making scarcity of these fine rifles a real issue, and a rifle that naturally fetches a premium price. Some consider it the finest Mauser ever produced.
Range Drop Windage Velocity Energy
6.5 Creedmoor 500yd -46.9 9.6 1900.1 1122.1 Ammunition, Hornady, 140 gain Super Shock Tip, 24″ barrel at 2,717 fps
6.5×55, M96 500yd -43.2 7.6 2047.1 1330.4 Handload, 46.5 grains RL22, Hornady 143 grain ELD-X (Extremely Low Drag-eXpanding) bullet used in a 29″ barrel at 2,754 fps.
Commercial Ammunition is easily found at a competitive price as compared to the least expensive common calibers. The best premium ammunition might be Lapua, but be sure not to purchase ammunition from European manufacturers that also sell 6.5×55 for modern rifles. This ammunition is labeled discretely as 6.5x55SE, or SKAN. Do not use this ammunition. first try a box of Privi Partizan 140 grain SP, or their 120 grain match load before spending the big bucks on Lapua. A M96 with a good bore is not picky.
Privi Paritizan 6.5×55 120 grain Match load, $1.36/rd
This is an affordable general purpose hunting round that may also shoot close to MOA or even tighter. I would expect the M96 to shoot 1.5 MOA groups or better with commercial ammunition. 1.5 MOA is accurate enough for targets out to around 500 yards. If you’ve got a sub-MOA load, then you are good out to 1,000 yards.
Prvi Partizan Ammo 6.5×55 139gr SP 20 per box. $1.25/rd
Sellier & Bellot SB6555C Rifle 6.5×55 Swedish 140 gr Full Metal Jacket (FMJ) 20 Bx/ 20 Cs $19.04/box.
Try some more expensive offerings if you need precision level accuracy. The worn barrel on my M1938 Swedish Mauser is a bit picky, so it takes longer to find an accurate load out of that barrel, but it can still shoots MOA once the correct ammunition is found. The 140 grain is the best choice if one is looking for accuracy.
If your Swede is a M94 carbine, then for the most accurate and best hunting ammunition, I would use 160-grain Hornady soft points. Essentially you would then have .30-30 trajectories and punch, and a good brush gun.
(To be concluded tomorrow, in Part 4.)