SHOOTING THE 6.5 X 52 mm, 7.35 x 51mm CARTRIDGES AND THE CARCANO RIFLES
The 6.5 X 52 mm cartridge has been largely ignored by both the shooting public and the industry despite large numbers of rifles in the publics hands. The 7.35 x 51 mm cartridge is even more obscure because of its’ step child status in history and its’ virtual total lack of interest by the shooting industry. The Carcano rifles have been largely ignored by military rifle collectors and have unjustly received much unfavorable press and commentary. This article will discuss the characteristics of the 6.5 X 52 mm and 7.35 x 51mm cartridges as well as the Carcano rifles and how to extract the most performance from each. Misunderstood characteristics of the Carcano rifles and unsubstantiated claims about safety and quality of the rifles will be discussed. Methods and components used by the author to extract the best accuracy and shooting pleasure from the ammunition and rifles will be detailed. The shooting and loading characteristics discussed will be from the view point of a collector desiring to reproduce the military specification performance as closely as possible with available components, striving for best accuracy.
6.5 X 52 mm:
The 6.5 X 52 mm cartridge was the primary small arms cartridge of the Italian military from the late 19th century until 1945 and was used in a reserve capacity well into the 1970’s. The cartridge was the first in a series of 6.5 mm military cartridges designed in the 1890’s. It was the first military cartridge to use a low errosivity, smokeless propellant, called Solenite. The cartridge was initially loaded with a double base propellant that was licensed from Dynamit Nobel called Ballistite. Ballistite had a very high percentage of nitroglycerine and it was found early on that the high flame temperature of the Ballistite caused excessive throat erosion. The Ballistite also showed problems with propellant stability at temperature extremes, which was unacceptable for a military applications. Solenite was also a double base propellant but with a significantly lower percentage of nitroglyserine. The lower nitroglycerine and other additives dramatically improved the errosivity of Solenite and it was adopted as the standard propellant in 1896. It is interesting to note that a nearly identical propellant was adopted by Great Britain in 1901 known as Cordite. The primary loading for the cartridge throughout its service was a 162-grain full metal jacket, round nose bullet measuring nominally .267” diameter, and 35.2 grains of Solenite. It is interesting to note the method I believe was used to load cartridges. I had long wondered how the extremely course large grain propellant was loaded in the small 6.5 mm neck. After doing some research I found that the British loaded the .303 round by loading the Cordite in a straight wall cartridge, then necking the cartridge to it’s final dimensions and then loading the bullet. This would have obviously been the same method the Italians used to load the 6.5 X 52.
A strain gage was fitted to a TERNI 91/41 rifle with an excellent condition bore and several lots of military surplus ammunition were tested. Measured pressures varied from 40,000 to 42,000 psi. Nominal muzzle velocities of the military ammunition vary from 2,130 fps / 649 m/s in the 17 3/4” barreled carbines to 2,295 fps / 700 m/s in the 30 11/16” barreled M91 rifle. The same ammunition was tested in a Committee Internationale Permannette (CIP) minimum specification test barrel with a piezo electric transducer and the ammunition tested 50,000 to 52,000 psi.
The 6.5 X 52 mm cartridge has taken a great deal of criticism as being underpowered and anemic. From a ballistic standpoint this is a little hard to justify. The Swedish 6.5 X 55 mm cartridge is considered an outstanding cartridge yet it is only able to produce 100 fps more velocity with a 156-grain bullet in the M96 rifle. The 6.5 X 55 requires a maximum average pressure of 55,000 psi and approximately 6 more grains of powder to produce this meager gain in performance. The .30-30 Winchester, regarded as an adequate deer rifle and known to have killed many moose and bear produces 2,220 fps in a 24” barrel with a 170 grain bullet. The 6.5 X 52 mm fires a bullet with a higher ballistic coefficient, at a higher velocity, shoots flatter and has far more penetration capability than the .30-30. From the standpoint of a service rifle cartridge the 6.5 X 52 with its relatively low operating pressure, coupled with its modest powder charge would result in much less barrel throat erosion and wear. This would equate to longer barrel life and decreased operating cost. In fact, much of what was done in the Carcano rifle/ammunition system was aimed at long barrel life, as will be shown later. From my point of view the 6.5 X 52 is a very efficient cartridge, offering adequate performance for what it was intended.
The only fault that one might level against the 6.5 X 52 as a military cartridge is that it had relatively humane terminal ballistics. The very long, blunt nosed bullet coupled with the fast twist rate of the gun resulted in a bullet that was very stable with a very high resistance to tumbling. The cartridge was known to have inflicted many “through and through” wounds, just leaving a small wound channel. The bullet typically would not tumble inside its’ target unless it encountered something hard such as bone. When it did tumble the wounding effect is well known.
7.35 x 51 mm
In 1938 the Italians introduced the new M38 Series of rifles and carbines, as well as a new cartridge the 7.35 X 51mm. The cartridge is simply the 6.5 X 52 necked up to .30 caliber. The cartridge is a true .30 caliber, with the military issue ammunition having a nominal bullet diameter of .299” - .300”. The cartridge came about as a result of the desire for a flatter shooting more lethal round. To facilitate these ends the bullet employed an aluminum core in the tip of the bullet, above a core of lead. This type of bullet design had been more than demonstrated by the British in the 174 grain bullet used in the .303 service round. This moved the center of gravity towards the rear of the bullet thereby causing the bullet to be substantially less stable. The bullets tumbled easily on impact causing far more traumatic wounds than the 160 grain round nose of the 6.5 X 52.
The pressure specification for the 7.35 X 51 was identical to the 6.5 X 52. The round was loaded with a 128 grain full metal jacket spitzer bullet and nominally 40.9 grains of a single base, extruded propellant. This type of propellant is essentially the same as the U.S. IMR type propellants. The single base, low flame temperature propellant along with the modest operating pressures made for very long barrel life. The round produced velocities of approximately 2,480 fps / 756 m/s in an M38 Short Rifle and approximately 2,410 fps / 735 m/s in the M38 Cavalry and T.S. carbines.
The Italian Army planned to convert to the 7.35 X 51 caliber but stopped in 1940, not being prepared for the War to begin as soon as it did. They could not logistically support both calibers of weapons and could not build 7.35 mm rifles fast enough to meet the demand once the war began. According to Dick Hobb’s research, units of the Italian 8th Army going into Russia in 1942 were issued 7.35 caliber Carcanos, but the guns were immediately exchanged for 6.5 caliber weapons. Subsequently most of the existing 7.35 M38 Short Rifles were given to the Finnish army and put to good use by the Finns. All T.S. and Cavalry carbines were retained in Italy. The M38 Cavalry carbines were given to a paramilitary youth organization for training.
The 7.35 X 51 is ballistically nearly identical to the .30-30 in terms of energy but shoots flatter because of the higher velocity and higher ballistic coefficient bullet. Had the Italians been able to field the 7.35 X 51 mm it would certainly have proved a very effective combat rifle for the time. The guns were light and easy to carry the wounding capabilities of the bullet were substantial. The ammunition produced mild recoil and essentially was the precursor to modern assault rifle ammunition, first fielded by the Germans in the 7.9 X 33mm. The design criteria being, a lightweight bullet/round fired at a modest velocity, larger quantities of ammunition carried by the soldier, and easy for anyone to shoot.
I will not attempt to make any detailed discussion of the many varieties of Carcano rifles. For those interested in that I will refer them to Richard Hobbs’ excellent book “The Carcano, Italy’s Military Rifle”. I will discuss some specific characteristics of the Carcano design in general and show how out of ignorance some of these have led to much of the bad press this rifle has received.
To begin this discussion the caliber of a rifle refers to the diameter of the bore of the barrel, or the diameter across the lands of the rifling. In the case of the Carcano rifles and for that matter every other 6.50mm caliber rifle this dimension is generally accepted as .257”. The CIP minimum specification diameter for the 6.5 mm Carcano barrel is .256 in / 6.50mm. The groove diameter of the barrel is where a considerable amount of ignorance arises in the Carcano rifle. Nearly every other 6.5mm caliber has a groove diameter of .263 - .264”. The exceptions to this are the 6.5 X 54 MS with a .266” groove and the Carcano with a CIP minimum specification groove diameter of .2677” / 6.80mm. I do not know what the production tolerances were for the Carcano, but based on my knowledge of current rifle manufacturing practice a tolerance of at least +.001” would be used for these dimensions. I have slugged the barrels of approximately 20 different types of Carcano rifles from 3 different manufacturers and have found barrel diameters in good condition rifles typically running from .2680” to .2690”. I have a 91-24 that has a groove diameter of .2710”. This rifle still has strong rifling and a somewhat shiny bore, but has seen a lot of use. Until very recently this bit of information has totally escaped the shooting sports industry. No bullets of the correct size were available, with the exception of only a few small bullet makers. This problem almost entirely has resulted in the Carcano being categorically called an inaccurate, poorly manufactured rifle. In fact noting could be further from the truth. 6.5 Carcano owners now have available to them as of the summer of 2002 an excellent .2675” 160 round nose bullet specifically designed for the 6.5 Carcano. This bullet is being offered by Hornady Manufacturing. The bullet is also being offered in ammunition loaded by Hornady for Graf & Sons.
A similar discussion applies to the 7.35 X 51 mm cartridge. The diameter of the grooves of the 7.35 X 51 mm typically run .300” - .301”. The diameter across the lands typically runs .290” - .291”. There is no specification for the 7.35 X 51 mm because no major manufacturer has ever had any interest in standardizing the cartridge. I have slugged the barrels of my two 7.35 Carcanos and one measures .300” and the other measures .301”. Several small bullet makers make appropriately sized bullets for the 7.35 X 51 mm. Bullets for the cartridge should be .299 - .300” in diameter.
The original 6.5 X 52 mm Carcano design used a gain twist barrel. The gain twist results in a very slow initial twist in the barrel progressively getting faster until the full twist rate is attained at the muzzle. The slow initial twist results in substantially less torque being imparted to the bullet during the highest loading phase of the interior ballistic cycle. This results in significantly less barrel wear in the throat. This coupled with the very deep rifling of the barrel would result in barrels that would have a very long wear and accuracy life. This in fact is the case. Many M91 model rifles show signs of considerable amounts of ammunition being fired through them, because of the crazed/frosted condition of the bore, yet still show very strong rifling and shoot well with the proper size bullets. The 7.35 X 51 mm Carcano rifles used a standard fixed twist barrel.
The Carcano bolt is the model of a simple, easy to field strip bolt. It is about as fool proof as you can get for a common soldier. The Carcano trigger has taken a considerable amount of criticism. The trigger is basically a Mauser type two-stage trigger. In almost all cases if you find the trigger rough or creepy simply polishing the sear and trigger mating faces result in a very acceptable trigger for a military rifle. For the most part I have found Carcano triggers have less creep, are more crisp and lighter than the majority of Mauser triggers I have encountered.
The materials used in the Carcano are excellent. These rifles were made from special steels perfected by the Czechs, for which the Italians paid royalties. If you have ever tried doing any work on a Carcano receiver you will find out just how hard and tough the steel is. The Carcano has also received a reputation as being a “weak” design. Nothing could be further from the truth. The Italians made a small run of Carcanos early in WW II chambered for 8 X 57 JS. The Germans rechambered some Carcanos to 8 X 57 JS late in WW II. These rifles were also proofed for this cartridge. The CIP minimum suggested proof pressure for the 8 x 57 JS cartridge is 73,500 psi. I hardly call this a weak action.
The best case I can make for the strength of the Carcano was a personal experience attempting to blow one up for a hunter safety course video. I was asked by the Department of Game and Fish of New Mexico about 12 years ago to help them with this. At the time I was one of the ones ignorant about the Carcano, believing it to be a weak action and easy to take apart. Well, the morale to this story was a full case of Bullseye failed to do anything significant to the action or barrel. We finally had to fill a cartridge case with C4 explosive and detonate it to get anything that looked like what we wanted. One other incident I have experienced with the Carcano further convinces me of the great strength of these actions. In my early experiments with .268” bullets, and loading data for them, I had several incidents of extreme pressure. The bolt had to be opened with a hammer and the cartridge case appeared to be a belted magnum. The headspace of the gun had grown slightly but otherwise was fine and has been fired many times since. I know from my experience as a ballistician that pressures in excess of 90,000 psi are required to do this type of damage to a cartridge case. A good condition Carcano rifle is as safe and strong as any other military bolt-action rifle you will encounter. This incident will be discussed later, as it was caused by propellants that should not be used in the 6.5 X 52 because of their ignition characteristics.
As far as quality of the rifles goes I have seen quite a spectrum, mostly due to condition or wear of the rifle. The production quality does seem to vary some from the different manufacturers in terms of fit and finish, just as Mausers do. However, I have several Beretta Gardone manufactured rifles in excellent condition that have as tight and smooth an action as any VZ 24 I have ever seen.
One design feature of curiosity on the Carcano is the recess cut in the bolt face and the recess in the rear face of the issue cartridge cases. As I understand from the Italian information on the rifle the initial cartridge case had intermittent problems with primer pockets leaking gas. The recessed groove in the cartridges served to crimp in the primer and provide a gas trap. The groove in the bolt face served further as a gas trap and to increase the sealing pressure between the cartridge and bolt face as I will discuss below. Subsequent future improvements in cartridge case metallurgy and manufacturing probably solved this problem. I can offer one other benefit it would have for a military rifle. This groove collects dirt and gunk that might accumulate on the bolt face or be introduced by a dirty cartridge. It would allow a considerable amount of dirt to be present and the bolt still close and the gun function.
The groove in the bolt face both creates a higher contact pressure between the bolt face and cartridge head as well as create a very useful situation for the hand loader. Because of the groove in the bolt the surface area contact between the bolt face and cartridge head is significantly reduced. This serves to magnify the contact pressure that exists between the bolt face and cartridge case during firing. The increased pressure makes it more difficult for gas to escape if the primer or primer pocket happens to leak. This condition also serves as a safety valve for the hand loader. In effect it exaggerates the force the rear of the cartridge experiences. This also increases the friction between the cartridge and bolt. In the Carcano you will feel stiff bolt lift long before you have reached any kind of dangerous pressure. This in no way makes the gun weak it is simply a by product of early efforts to solve what was primarily a cartridge case problem.
6.5 mm Carcanos were equiped with a wide variety of sights. Early model M91 series rifles had adjustable sights with a fixed battle zero sight. Most models of rifles made just before or during WWII had fixed sights. The exception to this was the M41 model. From a user standpoint the WWII era Carcano’s sights are the model of effectiveness and simplicity. The early model M91 version rifles with the fixed battle sight being at 300 meters was probably not the greatest decision but reflected the trend of that time. With this sight setting the rifles would have a maximum height of trajectory of approximately 15” – 17” at a range of 175 to 200 yards, depending on barrel length. I suspect more than one Austrian soldiers life was spared in WWI because someone shot over his head
The Italians apparently realized that a 300-meter battle zero was a bit impractical and with the introduction of the M38 models went to a 200 meter battle zero. This zero results in a maximum height of trajectory of 5.5” – 6.5” at a range of approximately 100 yards, depending on barrel length. With this sight setting, by simply holding on the middle of the torso, it would have been hard to miss the target out to about 220 meters. The Carcano’s also used a unique sight picture. The proper sight picture for regulated sights on a Carcano is with the front sight in the very bottom of the rear sight groove. This is how the Italian army manuals instructed that the sights be used. Potentially, this would allow for two battle sight settings. The normal use as mentioned above would be a 200 meter zero. Using the Mauser sighting method, the front sight level with the rear sight, would result in a zero of 330 – 350 meters. This is about the maximum range practical for attempting to engage a target with iron sights.
I contend with the Carcano the Italians had a very intelligent approach for a battle rifle. The fixed sights were basically fool proof. The Italians must have realized with the M38 models that nearly all small arms engagements occurred inside of 200 meters. The fixed sights with a 200 meter zero would have been fool proof for a soldier under stress, who was probably a poor judge of distance to begin with. The soldier would have had to do nothing but point and shoot at the middle of his enemy for ranges out to 220 – 230 meters. How much more simple and effective could it have been made.
Following is a table of different models of rifles with all the information needed to properly set one up with the sights regulated for the military issue type load, approximately a 160 grain bullet at 2,100 to 2,250 fps depending on barrel length. The table lists the approximate muzzle velocity for the different types of rifles with issue ammunition, the battle zero range, the front sight elevation/windage adjustment necessary to move the point of impact 1” at 100 yards and the proper height of trajectory at 100 yards for the given battle zero range.
TRAJECTORY COMPARISON FOR THE 6.5 X 52 mm CARTRIDGE
M91 CAV/TS M38 CAV/TS M38 SR M41 M91
VELOCITY: 2,110 2,110 2,150 2,225 2,270
BATTLE ZERO: 300 200 200 200 300
SIGHT RADIUS: 14.25” 14.25” 17” 23” 26.4”
ADJUSMENT FOR .002” .002” .0025” .0035” .004”
1” @ 100 YARDS:
H.O.T. FOR BATTLE
ZERO @ 100 YARDS: 13.75” 6.5” 5.75” 5.25” 11.5”
For those wishing to do their own trajectory calculations the ballistic coefficient for the Italian 162 grain FMJ RN bullet is approximately .275. A gun can be set up to be zeroed at 100 yards with the proper height front sight. You will probably have difficulty finding Carcano sights tall enough to accomplish this. To raise the point of impact the front sight must be lowered and just the opposite is required to lower the point of impact. To move the point of impact left or right the front sight must be moved in the direction it is off. Mauser front sights are a bit loose in the Carcano but can be made to work.
The sights on the 7.35 Carcano rifles are identical to the M38 6.5 mm rifles. The three models of rifles produced all had a fixed battle zero of 200 meters. With the military issue 128 grain FMJ load the 200 meter zero gives the rifle a maximum height of trajectory of approximately 4” at a range of 100 yards. The bullet is approximately 11” low at 300 yards. The practical result of this is that by holding on the middle of the torso of the target, a soldier was certain of a body hit out to a range of approximately 270 meters, approximately 50 meters further than the 6.5 mm cartridge.
The table below gives the same trajectory comparison for the 7.35 X 51 as the above 6.5 X 52 table. The figures shown are for a nominal 128 – 130 grain bullet with a ballistic coefficient of .285.
TRAJECTORY COMPARISON FOR THE 7.35 X 51 mm CARTRIDGE
RIFLE: M38 SR M38 Cavalry/T.S.
VELOCITY: 2,480 2,410
BATTLE ZERO: 200 200
SIGHT RADIUS: 17” 14.25”
ADJUSMENT FOR .0025” .002”
1” @ 100 YARDS:
H.O.T. FOR BATTLE
ZERO @ 100 YARDS: 4” 4.5”
6.5 x 52 mm:
The 6.5 mm Carcano presents several peculiarities when it comes to reloading. First, as I stated above, the military issue bullets were nominally .267” diameter. The only .264 “ bullet I have ever achieved any kind of reasonable results with is the Hornady 160 grain RN. This is due to the bullets long bearing surface. Even with this bullet I have some rifles that are hard pressed to shoot less than 5” at 100 yards. Shooting .264” spitzer pointed bullets in the Carcano is an exercise in futility.
.264” bullets are fine for informal plinking, etc. To get accuracy from the Carcano rifles and ammunition .267 - .268” diameter bullets must be used.
CAUTION: .268” bullets should not be used in any Vetterli rifle, which is intended for Black Powder loads.
As discussed earlier in the article some exciting things have happened for the Carcano owner in the summer of 2002. Hornady introduced a .2675” purpose built bullet for the 6.5 X 52. In addition, in the fall of 2002 Graf & Sons began selling Hornady ammunition loaded with the same bullet. The ammunition uses the excellent Privi Partizan cartridge case. Graf & Sons is also selling the cases as a component. Hornady has updated their reloading die set to accommodate the bigger diameter bullet.
Reloading dies present some issues for the 6.5 X 52. The current specifications for the 6.5 X 52 mm Carcano were developed by CIP. I have found that the specification for minimum chamber dimensions does not match that of a large number of rifles. The problem is in the minimum diameter of the breech end of the chamber. The minimum CIP dimension for this is .451”. After casting the chambers of a number of rifles I have found chambers with this dimension as small as .4485”. There are also rifles that are within the CIP specification. The largest chambers I have observed measure .4535”. All other chamber dimensions have been within the specification. I do not know how this discrepancy has come about. It could be an error in the CIP specification from the original Italian manufacturing practices or a result of original chamber reamers being sharpened too many times. I have also observed this dimesional discrepancy in 7.35 X 51 chambers.
The result of this is that reloading dies made per the CIP specifications are not correctly dimensioned for the tighter chambered rifles. Because of this the dies will not size the base of the cartridge enough to allow proper chambering in many rifles. I have only used Hornady dies so I can’t speak for other manufacturers, but as of the time of this writing Hornady is offering dies that account for this problem. Reloading dies should be made for a maximum cartridge base diameter of .447”. Figure 1. shows a drawing of a maximum cartridge based on the observed chambers. The correct headspace range is also shown for a .375” shoulder datum. This will allow you to check the headspace of your rifle with the Stoney Point headspace gages. I have used Hornady 7.35 X 51 mm New Dimension dies and have not had the resizing chambering problems like what have been encountered with the 6.5 X 52.
Norma 6.5 Carcano cases are very high quality. However, the cases extractor groove is narrower than the original specifications called for. The Norma cases will not function well. The feeding and ejection is difficult if not impossible in some guns. The narrow extractor groove tends to bind up in the stripper clip, compromising feeding, and also binds on the extractor during ejection. The recently imported Privi Partizan cases, also used in the Hornady ammunition, have correct extractor groove width. I have used these cases extensively and they function flawlessly.
For my shooting of the Carcano rifle I have used Hornady .2675” 160 gr RN bullet. These bullets are nearly an exact copy of the profile of the original 162 gr FMJ bullet. These bullets have produced excellent accuracy in a number of rifles, 1.5 “ groups at 100 yards being the norm instead of the exception. The only other .268” diameter production bullets I am aware of are offered by Buffalo Arms. See the excellent Carcano homepage for the address.
At this point in time a somewhat in depth discussion of the interior ballistics of the 6.5 X 52 is required as it pertains to the use of the .2675” bullet as well as primer and propellant selection. As I discussed above, when talking about the strength of the Carcano rifle, I mentioned some very high pressure rounds I had experienced. It wasn’t until I had a test barrel with a pressure transducer that I was able to determine the cause of this.
As I mentioned above Carcano ammunition in a minimum dimensioned test barrel fires at pressures of approximately 50,000 psi. This pressure is high enough that most any propellants will ignite and perform acceptably. However, as I also mentioned above the same ammunition in most Carcano rifles fires at pressures of approximately 40,000 psi. This is because of the larger chamber and bore dimensions encountered in the rifles. At pressures not much below this the ignition characteristics of many slower propellants, that might be used in this cartridge, become very erratic. With some of the larger bore guns and rougher barrels some of these propellants can become down right dangerous.
Essentially what is happening is that the slower extruded propellants, starting with propellants like N150, Hodgdon / IMR 4350 and slower propellants have chemical deterrents that slow the initial burning rate of the propellant. These deterrents also make these propellants harder to ignite. Because of the very deep rifling in the 6.5 X 52 significantly more force is required to engrave the bullet into the rifling with a correctly sized .2675” bullet than most other rifling forms. This coupled with a bullet with a long bearing surface, and a possibly rough throat, can result in a bullet that requires a lot of initial gas pressure to engrave and keep the bullet moving while being engraved. What can happen is the bullet will stop in the throat before some of these propellants really get going and you then have an obstructed bore. Not Good!
The practicle application to the 6.5 X 52 is that there are propellants that should absolutely be avoided in this cartridge. With the .2675” Round Nose bullet I absolutely do not recommend any extruded propellants slower than Hodgdon Varget. Do not use Vihtavuori N150 or other extruded propellants any slower as they exhibit very erratic ignition characteristics. Some propellants even show this erratic performance at maximum charges. Nearly all these propellants show erratic behavior at charges reduced from maximum. Only use a magnum primer. The above behavior of propellants has not been observed with Ball Powders.
Generally this behavior will not occur with .264” bullets because the engraving forces are much lower. They also have a built in safety valve because they allow gas to blow by the bullet because of being undersize.
I have not attempted to produce an extensive list of propellants for reloading. Hornady has published data for the .2675” Round Nose. I will only show the propellants I have found to be safe and offer performance nearly the same as issue ammunition al,ong with good accuracy. Following is a table of my pet loads.
Cartridge: 6.5 X 52 mm
Bullet: .2675” diameter Hornady 160 RN
Case: Privi Partizan
Primer: Winchester WLRM
Cartridge overall Length: 2.980”
POWDER WEIGHT M41 VELOCITY (fps) M38 CAVALRY VELOCITY (fps)
H414 37.0 gr 2,210 2,080
WC 760 38.0 gr 2,225 2,090
These are maximum loads, do not exceed.
For a starting charge do not reduce either propellant more than 5%.
Maximum case length: 2.067”
Trim Length: 2.057”
Maximum cartridge overall Length: 3.012”
The above loads were tested in the instrumented M41 rifle and are within the pressures tested for military issue ammunition.
7.35 X 51 mm
As I discussed above the 7.35 X 51 has no current specification. It uses a nonstandard bullet diameter. In the late 60’s Hornady made a 128 gr Spire Point bullet in .300” diameter specifically for the 7.35 X 51. It was discontinued after several years because of a lack of interest.
The 7.35 X 51 mm requires bullets of .299” - .301” diameter. Do not attempt to reload this cartridge with .308” bullets.
There are several small manufacturers that offer bullets in this size range. These manufacturers can also be found on the Carcano internet homepage. For my testing I had a swage die made by Corbin that reproduces the profile of the original FMJ bullets at a diameter of .301”. I reswage Hornady .308” 150 grain FMJ BT and .310” 123 grain FMJ bullets in this die to .301” flat base bullets. In my testing I have found that the reswaged 150 grain bullets shoot very well. I have not achieved as good a results with the 123 grain bullets.
No cases are currently manufactured for the 7.35 X 51 mm. However, it is quite easy to form 7.35 X 51 mm cases by running 6.5 X 52 mm cases into a 7.35 mm die to neck up the cases and then trimming the cases to the proper length. The neck on the Norma 6.5 X 52 cases is quite thick as compared to original specification ammunition. If Norma cases are used to form 7.35 X 51 mm cases it will be necessary to turn the case necks to a thickness of .013” maximum. If the cases are not neck turned the loaded ammunition will not chamber in many rifles. The new Privi Partizan cases do not have this problem and can be directly formed into 7.35 X 51 mm and trimmed. I have found these case to function flawlessly.
As of the writing of this article, October, 2002, Hornady is again planning on bring out a .300” 128 gr bullet for the 7.35 X 51. If this does indeed happen it will be a real shot in the arm for Carcano owners. Support and shooting of this product will ensure the continued availability of the bullet. FIGURE 2.
Below is a table showing the results of my testing with the bullets described above. Again I did not attempt to develop an extensive list of powders. I simply wanted something that would shoot well and produce good accuracy.
Cartridge: 7.35 X 51mm
Bullet: .301” reswaged Hornady 150 grain FMJ
Case: Reformed Privi Partizan 6.5 X 52
Primer: Federal 210
Cartridge overall length: 2.980”
POWDER WEIGHT M38 SR VELOCITY (fps) M38 CAVALRY VELOCITY (fps)
N135 36.0 2,175 2,110
Benchmark 34.5 2,140 2.090
Loads shown are maximum, do not exceed.
Bullet: .301” reswaged Hornady 123 FMJ
Cartridge overall length: 2.850”
Maximum case length: 2.015”
Trim length: 2.010”
POWDER WEIGHT M38 SR VELOCITY (fps) M38 CAVALRY VELOCITY (fps)
N135 38.0 2,440 2,365
Benchmark 37.0 2,470 2,410
Loads shown are maximum, do not exceed.
6.5 x 52 mm
The Carcano rifles are capable of outstanding accuracy. With the exception of a military issue type load in the short carbines they are very pleasant to shoot from a recoil standpoint. Because of the above mentioned sight picture for the Carcano, front sight in the bottom of the rear sight notch, it is very important to have a consistent stock-cheek weld for consistent accuracy. It is often very helpful to use a carbide lamp or a sight black product to blacken the sights, which improves contrast and sight picture.
With .264” bullets the best results I have ever been able to obtain are with the Hornady 160 gr RN. Most rifles will shoot groups with this bullet in the 3” - 5” range at 100 yards for 5 shots. I will occasionally get a group under 3”.
With the Hornady .2675” bullet I have been able to consistently shoot my M41 under 2” at 100 yards with numerous groups around 1.5”. I have with my accuracy marked M38 Short Rifle shot groups under 1” at 100 yards with the norm being 1.5” – 2.0”. With the Cavalry and T.S. model rifles I can typically shoot groups in the 2.0” – 3.0” range. The accuracy shooting with the carbines is somewhat limited by the very short sight radius.
I have never had a chambering problem with the .2675” bullets. Any problems have been traced back to the chamber dimensions and size die as I mentioned above.
7.35 x 51 mm
I have also found the 7.35 mm Carcano rifles to be capable of very good accuracy with the proper bullets. With the 150 grain .301” bullets I described above my M38 Short rifle will shoot groups typically 1.5” – 2” at 100 yards. The same bullets in my M38 Cavalry rifle will shoot 1.5” – 2.5” at 100 yards.
The 6.5 X 52 is a very useful and capable cartridge. It served well as a military cartridge for over 80 years. The 7.35 X 51 would have been an even more effective military cartridge than the 6.5 X 52 had its timing been different. It is interesting to note that the .308 Winchester / 7.62 X 51 mm NATO and the 7.35 X 51 mm are nearly the same dimensions. Both the 6.5 and 7.35 cartridges are fun to shoot and properly loaded capable of very good accuracy. The Carcano rifle is a well made rifle that is by no means weak or poorly manufactured. They are reliable and strong rifles that are fun to shoot and offer a tremendous variety of types and markings for the collector. I will admit that they are a rather utilitarian rifle as compared to some others. However, they are probably one of the most efficient, cost effective, user friendly battle rifles produced in their era. The rifle, ammunition combination properly loaded is capable of accuracy that will rival the most accurate of the Mauser chamberings.
*A SPECIAL NOTE ON CARCANO RECEIVER STRENGTH:
The TV show " Mythbusters " ( 2007 ) tried to blow up a Carcano rifle will little success. All manner of excessive loads proved the action really is stronger than it looks. A plugged/welded barrel caused the barrel to fail but the action held.
If you feel that you have an unsafe Carcano rifle /carbine due to poor design or manufacture, I will give you $50.00 cash for the firearm and pay for shipping to me.
REFERENCE 1: “CENTENARIO DEL FUCILE ‘91” . LATERZA, ROMA 1991
REFERENCE 2: Simone, Belogi, Grimaldi: “Il ‘91” . Ravizza, Milano 1970
REFERENCE 3. Hobbs, Richard, “The Carcano, Italys Military Rifle, Cameron Park, CA, 1996
REFERENCE 4. Lambley, Andrew, “CORDITE”, Handloaders Digest 1996, 15th Edition
Re-post of article by Dave Emery.
Tonkin Gulf Yacht Club
President NM MILSURPS