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This is a compilation of all my posts related to reloading the 8x50R Austrian cartridge.
Getting into the manufactury of 8x50R
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I just had to go and buy that Budapest M95 original stutzen. It bugs me to have a weapon without ammo. That's about as good as having a car without gasoline. So, what can one do but forge ahead and get into putting some 8x50R into production.
I bought the CH/4-D 8x50R die set from Buffalo Arms. They also have brass, which I have not seen. It sells for ninety cents per case, so you could get 100 of them for $90. That's more than I paid for the stutzen.
Cases can be made for the 8x50R by using 7.62x54R, which I may get around to. This requires a fire-forming process which is not difficult. I decided instead to put to use some fired 8x56R Berdan-primed cases of Bulgarian origin, which I wasn't doing anything with anyway. I use the technique we have mentioned in another post whereby you remove the fired Berdan primer, drill/grind out the primer anvil, and drill a new flash hole. After this, you solder a fired .22 rimfire case into the primer hole, and cut it off. If done properly, the large rifle boxer primer fits nicely. I have done this enough now that I can do it with some precision. I will not try to tell you that it isn't a lot of work.
After you have squared away the primer pocket, you reform the 8x56R case in the 8x50R sizing die. Be sparing with the lube, as it is easy to get dents. If you do, don't worry, they will flatten out in first firing. The reformed case will be too long and need trimming. The Bulgarian cases are good, strong brass and trimming 6mm of brass is strenuous. I decided to use a Dremel tool and cut off the first 5mm, then trim the last 1mm in my Hornady case trimmer. I did not neck ream the case, although this material is bound to be thicker than the original case mouth area. Chambering a finished round showed no signs of a new case mouth being too thick.
I selected pulled 150 gr Turkish .323 bullets for my first experimental firing. This is because of the odd situation whereby the original 8x50R used a .323 bullet with obturating base in a .329/.330 bore. The CH/4-D dies have a .323 expander ball. That Turkish bullet, while at around 150 grains is much lighter than the original Austrian bullet (at what, 245 grains?), does have a coned base which might just give the obturation needed and be a good bore rider. Added later: Velocities do not tend to bear this out.
Powder is 40.0 grains of milsurp IMR 4895.
I will report my range results after I do my first firing.
I think I will see if I can get a expander ball in .329 for these dies also, to be able to use the Lee cast 205 gr. lead bullet. I could just lube the inside of the case necks, and using my 8x56R die, drop the cases only so far into that die so as to use only the expander ball to open up the neck. That would involve two processes, so I would rather have the correct expander ball for the CH/4-D die.
A note on re-forming cases in dies. As Lee points out in their FAQ on their web site, re-forming cases in ordinary sizing dies is not the same as using special dies purposely made for re-forming. These have different dimensions to compensate for spring-back of the material being re-formed, as metal has something of a memory. In the instance of the M95's and possibly most milsurps, the lesser degree of precision in the chambers probably makes this a non-issue.
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Okay, I just got back from the gun range after firing my first 8x50R products, as described above. I am very pleased with the results. Out of 18 rounds fired, no split cases; some random dents from re-forming nicely ironed out. The .323 Turkish bullets raced down the bore and hit the paper target with a reasonably small pattern, but printing high. This is a stutzen with the original front sight base directly on the barrel, not with a banded frontsight base. The original sight blade is very low; you can barely see it over the handguard. With the original long, round nose bullet of the 8x50R of what around 245 grains, the recoil time (bullet time in bore) is longer than with a lighter bullet. Actually, I expected the lighter bullet to print lower, not higher. One of my Bulgarian reworked 8x56R rifles had a front sight blade that was too tall; it printed way too low on target. To correct this, I sent to good ol' Tennessee Gun Parts and got the correct lower one and stashed away the too-tall one. Now I have a use for it if I am going to stay with the light bullet for the 8x50R.
Next, I am going to fire-form some 7.62x54R brass per, I think it was, one of Nam Barney's posts, and make some 8x50R that way.
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Next phase, using the Graf 7.62x54R brass made in Serbia. I used the conversion data from Nam Barney's post re. "where to get 8x50R dies" on this forum. In using the pre-fireforming "trim to" length, I would change that to 1.98, not 1.95, as mine came up a bit short using 1.95 in my dies and Graf brass. You can always trim a little more later if they are a taste too long; you can never go back and replace shaved brass.
In turning these Graf cases back, I found out right away that they are MUCH thinner and softer than the converted Berdan Bulgarian cases used previously. Maybe this explains why I have gotten so many firings out of these converted Bulgarian cases that I have used in my 8x56R guns. As I have stated in another post, the paper tag found in one of the zinc cans containing the 1938-41 Bulgarian 8x56R ammo identifies this ammo for machine gun use. I have also noted that the rims are thicker than the German ones. When fired in machine guns, the propellant is still burning when the case is moving out of the chamber, so maybe this is the reason these cases are so robust.
At any rate, when attempting to seat the same .323 Turk bullet in the case mouth of the converted Graf 7.62x54R case, right away I could see problems with bullet pull. The "seated" bullet could be pushed right into the case with about 3 inch pounds of pressure. The case walls are about half as thick as the Bulgarian.
Actually, the above problem solves itself. I wanted to use some 205 grain gas checked lead bullets in this rifle, as it does have a .330 bore. This was a problem with the CH/4-D dies, as it is set up for use with .323 bullets. Even when I expanded the case mouth to .329 using my 8x56R die, the .329 bullet could not be properly seated using the CH/4-D die as the opening in the top of the seater die body is no larger than .324. The lead bullet gets to the first driving band, and then it hangs up in the top of the CH/4-D die and keeps getting pushed until the die reaches the case mouth. By that time, the bullet is seated too deeply into the case. I am sure you could return the die to CH and have them relieve the top of the die out to accept .329 if you wanted to.
Back to the solution of the over-sized Graf converted brass. In its present size, the case mouth wants, say, around a .325 bullet. The lead bullets I wanted to use are .329, so that is only .004 larger. Using a Lee universal case flaring tool, I slightly flared the case mouth to accept the .329 bullet, and they slipped right in there. A very slight bulge can be seen being made by the driving bands, but with brass this thin, it doesn't take much. I seated the bullet only so far into the case as to allow the gas check to remain just inside the case neck. When seated thusly, the opening of the case mouth is lined up right in the middle of the grease groove behind the second driving band. The result appears similar to the original military round, with that long round nose bullet sticking way out. Even though the CH/4-D die will not allow a crimp to be made using the .329 bullet, my flared case mouths got straightened out; they must have gotten just into the neck area of the seater die. If you have sufficient bullet pull, crimping lead rifle bullets is not desired nor necessary anyway.
The powder charge used for the .329 lead bullets was the now-familiar Harris load of 16.0 grains of H-2400. Using the Graf 7.62x54R brass, I found that the Winchester Large Rifle primers are a little loose, so for a tighter fit I went up to Federal 210's. I keep a wide selection of all kinds of primers on hand, because I find that so much variation can be encountered as to fit and hardness in relation to a given case used. This is just to adapt to a manufacturing process, if you will, and having nothing to do with actual performance.
Comments about the CH/4-D die set. For one thing, when you are accustomed to using one or two brands as I am (Lee and RCBS, one set of Hornady), getting used to the idiosyncrasies of another brand is irksome. For another thing, I bought the CH/4-D die set as a "price point" issue: they cost less than RCBS. After looking at the CH/4-D set and using them, if I had to do it over again, I would pay the extra $30-40 dollars and get the RCBS. I realize that much of the reason that these 8x50R dies (both brands) cost so much is because they are a "specialty" caliber and manufactured in small numbers. Having made that observation, I also noticed that the price is about the same for common calibers made by CH/4-D, so that argument isn't fully true for that brand. As to quality, it is my opinion that Lee dies are better made than my CH/4-D set. Therefore, the CH/4-D 8x50R die set logically shouldn't cost more than Lee dies. This also explains why CH/4-D is way behind 6 or 7 other major brands of dies in percentage share of market penetration.
One other comment about the 8x50R CH/4-D dies. I have never had a sizing die that gave me as much grief in the way of oil dents, for some reason. I've had the problem with both Bulgarian and Graf brass as discussed above. I have to wipe the case clean of lube in the shoulder area to have any chance of avoiding a dent.
Although the 8x50R has a bore size of .329 to .330, the original bullet size was .323 (same as "S" bore Mauser 8mm). The idea apparently was that the base of the original bullet used would obturate upon firing and seal the gases behind the bullet even though it was under bore size (the rifling is .323).
The loading dies in 8x50R that I bought from CH/4D are set up to use .323 bullets. Most commercially available .323 bullets are not designed with bases that are intended to obturate much if any. I have used pulled Turkish .323 bullets with success as to accuracy; I don't know if they obturated or not, but they did group okay.
I ordered a .329 expander ball from CH/4D for use with my 8x50R dies for when I wanted to use .329 bullets. I have loaded .329 LEAD bullets in 8x50R cases, but not jacketed ones.
My experience with brass for reloading this round is that cases formed from Graf 8x56R recent-import stuff have fairly thick walls; same comment for older European-made cases reworked into 8x50R configuration. With these, you get sufficient bullet pull to hold onto a .323 jacketed bullet. Not so with the Serbian-made 7.62x54R cases reworked into 8x50R's; the brass is too thin. With the latter, I simply used .329 LEAD bullets seated into the cases resized with the original .323 expander ball.
I do not have any experience with using RCBS or any other brand of dies in 8x50R caliber. The usual caveats apply about using a safe gun, using safe reloading practices, etc.
Range report on 8x50R
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I got a chance to get out to the Everett Sportsmen rifle range today and check out a few loads. I have had some 8x50R reloads of my own making here that I wanted to try out, for one thing. It was touch and go with the rain; the chrono got a little dew on it before I got done. Worse, I chronoed some brass case shotshell loads before working with the rifle cartridges, and fiber wad debris got blown all over the chrono. I had to clean this off before I could get good readings.
I had two loads prepared, one with a jacketed bullet and one with a cast lead bullet.
Starting with the jacketed bullet load, I used milsurp Turkish pulled 8mm (.323) bullets of 150 grains. More comments on this bullet later. The propellant charge was 37.0 gr. of milsurp IMR 4895. Primers used were WW LR.
For cases on these loads, I converted some Bulgarian surplus 8x56R 1939 and 1941 dated Berdan-primed cases to accept boxer primers. This is a story in itself. After conversion of the primer type, I cut them down and re-sized then to 8x50R. I have converted these cases before to accept boxer primers, but used them in their original 8x56R configuration with success. Apparently, it is asking too much from this old brass to it to take the re-sizing to 8x50R. Of the 20 cases I had converted, 16 failed at the new neck. Only 4 did not split. It was an experiment and I will close the book on this possibility. Added later: Of the four that did survive the first firing, all four are still good after several more firings.
The jacketed bullet loads with 37.0 gr. of milsurp IMR 4895 clocked an average muzzle velocity of 1646 with a standard deviation of 31.80 on one string, and 1645 with SD of 20.91 on another string. Accuracy was fair at 50 yards.
That muzzle velocity in the mid-1600's is too low, in my opinion, in relation to the potential of this powder. 38.0 gr. of IMR 4895 in a .300 Savage, for example, gives around 2400+ fps with only one grain more.
So what's going on with this powder? More like what's going on with the bullet. As we have discussed before, the 8x50R has a bore diameter of .329/.330 but originally used .323 bullets with an obturating base of some sort to seal off the gas. Also, the original bullet was much heavier, around 220 gr. or thereabouts, and had a long shank for better stability in a bore-rider design. When I use .323 Spitzer bullets of 150 gr., not only do they lack the long shank of the original bullet, but they do not have the obturating base so probably are not sealing the propellant gases off properly. With gas blow-by, the velocity goes down.
I also noticed plenty of evidence of unburned powder granules; this may re-inforce the gas leakage theory. If too much gas is lost too soon, all of the powder may not ignite properly and this would also cause a decrease in velocity.
My next experiments will be with jacketed .330 bullets.
The next load with a cast lead bullet was more satisfying. These were made with a nominal 205 grain lead bullet case from the Lee mould and sized to .329. The propellant was 16.0 gr of 2400 and WW LR primers were used. The average muzzle velocity was 1344 fps and the SD was 33.09. It didn't take long to figure out where the shots were printing and once I knew this, I could plop them all into the back ring at 50 yards. Because of their leisurely departure from the barrel, these lead bullets print about 4 inches high at that range.
The cases I used for this batch were Graf 7.62x54R, cut back and re-sized to 8x50R. The brass on this case is thinner than re-sized 8x56R, so it will not hold a .323 bullet. It holds a .329 lead bullet just fine.
More on Reloading the 8x50R
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This is one of those cartridges that forces me to learn more about it every time I load it.
In a previous post, I discussed how my dies (CH/4-D) were designed to be used with .323 bullets, as the original long heavy bullet was in this diameter. The bore is .329/.330, so the original bullet rides the rifling and has an obturating base to seal off the gases. Since we can't get bullets of this design to reload with, it is my view that some gas escapes around the kind of .323 bullets that we are able to get with conventional bases. I come to this view by getting a 1700 fps velocity out of a propellant charge that has potential for giving me over 2000 fps.
I have had success in using .330 lead bullets in 8x50R loads. After my last experiments with .323 jacketed bullets, I resolved that my next experiments would be with .329 jacketed bullets.
In preparing to do this, I prepped my cases by sizing them using a .323 sizing ball. I do this because the Graf 7.62x54R cases that I have cut down and resized to 8x50R have case walls that are too thin to hold the jacketed bullets tightly for which they are nominally sized. In sizing them to .323, they will hold the jacketed .329 tightly.
I started to use Hornady .338 bullets resized down to .329/.330. These are the 200 grainers, and when re-sized, the shank of the bullet (bore diameter) is forward of the cannelure. Normally, I like to crimp into the cannelure on 8x50R and 8x56R because both of these cartridges have fairly short bearing surfaces to grip the bullet in the case mouth.
I cannot say for other die sets, but when using the CH/4-D outfit that I have, you cannot crimp into the cannelure of a .329/.330 bullet that has any of the shank forward of the cannelure. This is because the opening in the die above the crimping shoulder is just a hair larger than .323 (the bullet size they were designed to use with), and a .329/.330 bullet will not pass through this hole.
Next, I turned to the Hornady 205 gr. spitzer bullets that are made in .329 (available from Grafs). With this bullet, the shank starts just after the cannelure and I was able to seat and crimp these bullets as I wanted to.
A person could go ahead and use the re-sized bullets, but without a crimp.
More still on reloading the 8x50R
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Another trip to the range today taught me more about this cartridge and the rifle it is chambered for.
In a previous post, I mentioned that next I was going to try some .329/.330 jacketed bullets so as to get the proper gas sealing that we are unable to obtain with the bore-riding .323 bullets currently available. See previous post for details on why this is.
Most of my test cartridges were loaded using cut-back and reformed 7.62x54R Graf cases, which I have previously described as having thin brass compared to original factory-loaded 8x56R cases which I have modified to use in 8x50R.
A small number were loaded using milsurp converted 8x56R cases.
I fired off the test rounds with the modified 7.62x54R cases using the following load data:
205 gr. Hornady .330 spire point
40.0 gr. IMR 4350
WW LR primer
This combination clocked an average muzzle velocity of 1431 fps with a standard deviation of 15.57; it was reasonably accurate with a front sight re-regulated to shoot to point of aim.
The approximate muzzle velocity of original factory loaded ammo for this round with a 244 gr. bullet is 2030 fps, so my load with 40.0 gr. of IMR 4350 isn't a barn-burner. It is pleasant to shoot, and remember, slower powders in larger calibers often yield slower velocities unless you have a large case that will hold lots more powder.
Next in line for testing was the small lot loaded to the same specs only using the modified European factory 8x56R cases with the thicker brass.
These would not chamber completely so I was unable to test these. I have never Cerro-safed the chambers of these rifles, but when I got home I looked into the chambers with a strong flashlight. With the smoking of recent firing, it was plain to see what the problem was. That section of the chamber where the mouth of the case (with bullet seated in it) is positioned is a different size between the 8x50R and the 8x56R. The 8x50R chamber mouth is only slightly larger than the diameter of the bore which is approx. .330 (remember that the 8x50R bullet is a bore-rider and doesn't fill in the grooves of the rifling). On the other hand, the 8x56R chamber is stepped at that exact point where the case mouth ends and the rifle bore begins. This is to allow a little more room for the case neck material while holding a bullet that is sized to the actual bore (such as is more common).
The differences really are not all that great; the original outside diameter of the case neck with bullet seated on an 8x50R cartridge is .356; the 8x56R is .358. My cut-back and re-sized 8x56R cartridges with .330 bullet seated measure .361, so a few thousanths are enough to make the difference. The modified 7.62x54R cases with .330 bullet seated measure only .351.
When I shoved the cases with thicker brass and a .330 bullet into the chamber, they would not go all the way. When I pulled a stuck cartridge out, you could see the burnishing marks on the case neck area where it had contacted the chamber walls 100%. This same load using the thinner Russian brass worked fine, as there must have been just enough room.
One other difference that I noticed between the 8x50R rifle and my others chambered in 8x56R. Alongside each side of the magazine follower are guides machined into the receiver. These guide the cartridge into the chamber as it is stripped out of the charger clip. I notice that when I use pointed, shorter (than original) bullets, the cartridge tends to tip up more on the bullet end and doesn't want to chamber properly. When I have loaded 8x50R with long, round-nose bullets, this problem goes away.
Tonight when I was looking over the problem with the chamber design vis-a-vis bullets used, I decided to compare the cartridge guides in the receiver of the 8x50R rifle to those in the 8x56R rifles. I only have only rifle in 8x50R to use in this comparison, but it looks to me like the rifles converted to shoot 8x56R have had a slight modification on the these guides. The guides seem to have had the upper edges trimmed down a bit and are not as sharp-edged as those in the 8x50R. Changing the shape of these guides would change how the cartridge was directed into the chamber and this must have been necessary due to the change in the bullet design.
Added 11-26-05
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The experiments with this caliber continue.
185 gr. Remington spire point (bulk bullet) .323
42.0 gr. IMR 4350
CCI 250 mag primer
Cut-down & reformed military 8x56R case (boxer primer conversion)
Avg. muz. velocity 1398
Standard deviation 16.97
205 gr. Hornady spire point .330
42.0 gr. IMR 4350
CCI 250 mag primer
Cut-down and reformed Graf 7.62x54R case
Avg. muz. vel. 1423
Std. dev. 25.62
Compare the data above to that of "Old Western Scrounger" brand of custom-made 8x50R ammo with a 220 grain bullet, below:
Avg. muz. velocity 1854
Standard deviation 12.54
The Old Western Scrounger ammo has respectable velocity (for this caliber and bullet weight) and a good spread. This ammo is no longer being sold. The comparison shows me that I have a way to go to duplicate the OWS performance because I have been conservative. On the other hand, this is never a bad idea when you are experimenting with loads. I will disassemble one of the OWS loads to "see what I can see."
Added later: Upon disassembling one of the OWS loads, the powder used appears to be H380 in a quantity of about 48.0 grains. THIS IS NOT A LOAD RECOMMENDATION, as I have not tried it myself.
When using the pointed bullets in loading 8x50R, they often do not feed well. The rifles re-worked to shoot 8x56R have modifications made to the ramping in the receiver to take care of this. Long, round-nose lead bullets feed fine in the 8x50R, but heavy, round nose jacketed bullets are difficult to find in 8mm (.323). Some time soon, I will try 170 gr. RN jacketed bullets for feed. See my previous notes on reloading this caliber as to why you can use .323 or .329/.330 bullets in this rifle.
Added 12-11-05:
When I was at the gun show yesterday, I spotted a box of 100 Hornady .338 bullets, 250 grains, jacketed round nose. They were only $5 (Midway lists them for over $22) so after looking them over bought them.
This bullet has a long, fat profile similar to the one used in the original loadings of 8x50R. Resized down to .329 using a Lee sizing die, it should be a good candidate for reloading 8x50R. Of course, it does not have the obturating base like the original. See some of my previous posts on reloading this caliber as to why this is an issue.
At first I thought this bullet would be a tough one to resize because of its long, fat profile. After lubing them, I started off with the resizing process and they went through quite easily. This bullet has a rounded heel design on the base of the bullet, which allows for the bullet to resize uniformly along its full length. I have found that some designs with a sharp edge on the heel (like Speer) tend to spring back to about .3295 after resizing. What you wind up with is a bullet which has a slightly greater size at the heel than along the rest of is length of bearing surface (which you want to be .329). When you seat bullets like this, the brass case mouth gets expanded out to .3295 along its full length and you don't get quite the tension on the bullet that you want.
Now that I have these resized to .329, I will go ahead and resize a portion of them down further to .323, which is the original bullet diameter used in 8x50R (albiet with an obturating base). This way I can experiment with both sizes and see what how the chrono data differs. Again, I refer to my earlier posts on the subject as to why I will do this (bore diameter versus land diameter).
I have previously referred to possible problems with using resized jacketed bullets (accuracy, velocity spreads). Since the proper bullets for this cartridge are not available, I guess I will have to live with this possibility. Also, when you are presented with low-priced .338 bullets, the negative aspects of resizing tend to fade.
Another positive about using this long, round nose bullet is that there should be no problems with feeding from the magazine as sometimes happens when spitzer bullets are used in 8x50R loadings.
Added 12-11-05:
I loaded 20 rounds of 8x50R tonight using the new-resized 250 gr. round nose bullets in two batches. One used the .329 bullet and the other the .323. Today was clear and cold and would have been a good day to go to the range, but just couldn't get it all together to do so. I will have to wait for another clear day, and what with the Christmas workload, will probably be after the holidays.
It never surprises me to encounter new problems with loading the 8x50R and tonight was not different. For these loads, I decided to use some "new" brass that I ordered from Buffalo Arms. Actually what it is, is re-worked RP .45-70 brass. It has been shortened, reformed, and a grove cut just ahead of the rim which also has been trimmed a little.
I have learned to load only one or two with reformed cases, just to see how they work before you load a bunch that won't work. Sure enough, I put the newly loaded round in the rifle and it wouldn't fully seat and allow the bolt to lock. I checked the diameter of the case where the bullet seats and it was under (both .329 and .323 bullet versions were checked), plus the neck had no marks on it so that wasn't the problem. The rim was engaging the bolt face okay, so that wasn't it either. I looked closely at the case and could see some marks on the neck, and sure enough, determined that the new case wasn't sized properly. The shoulder had not been set back far enough. So, I had to go back and resize all of these "new" cases. After sizing, I annealed the necks as this had not been done by Buffalo Arms. After that things went a bit better. Now I just have to take them out and test them.
I don't think I will be buying Buffalo Arms 8x50R cases in the future. After using theirs and my own made from 7.62x54R, I think I prefer mine and they cost a lot less.
These loads with the long, round nose bullet sure look a lot more like the original loadings than any other that I have loaded. They cycle better through the action too.
Added 12-18-05:
Another trip to the range today found me still looking for answers with the 8x50R. On this occasion, I tried some of the 250 grain round nose Hornady bullets resized to .330 that I referred to in my previous post entitled "Have I found a good bullet for the 8x50R?" Indeed I have. The rifle likes these bullets.
My experiments involved some of these 250 gr. bullets resized to .330. The results are as follows:
250 gr. Hornady jacketed RN bullet .338 resized down to .330
50.0 gr. Hodgdon H-1000
CCI #250 magnum primer
Buffalo Arms brass (re-worked .45-70 RP brass)
Average muzzle velocity: 1524
Standard deviation: 7.77
Same components as above, but using 46.0 gr. IMR 4350:
Average muzzle velocity: 1675
Standard deviation: 14.38
Good accuracy was obtained with all of the above loads.
Using the heavy 250 gr. bullet, the rear sight required elevation only to the first notch at 50 yards (lowest, fixed setting in the bottom of the sight ladder) to compensate for bullet drop. The original front sight for the 8x50R Stutzen was quite low; no doubt it was so equipped due to the use of the original heavy bullets.
You can expect decreased muzzle velocities using heavy bullets and slow stick powders. However, both work best with each other and give low, safe pressures and reasonable recoil. With a powder as slow as H-1000, for example, you can't get enough powder in the case and still seat the bullet to get even close to a dangerous pressure. Don’t worry about throat erosion using slow powders in these rifles. You probably won’t be able to shoot them enough in your lifetime to see appreciable erosion. The rifling leade in this chambering is so far out there from the case mouth that the burn has cooled a little before it gets there.
Other experiments with this caliber on the same day:
170 grain RP jacketed RN bullet .323
49.0 gr. H414
CCI 250 mag primer
Reworked military 8x56 cases
Average muzzle velocity: 1788
Standard deviation: 87.51
Lousy spreads and not particularly accurate.
200 gr. Nosler partition bullet .323
47.0 gr. H414
CCI 250 mag primer
Reworked Graf 7.62x54R cases
Avg. muz. velocity: 1629
Standard deviation: 13.89
Not accurate.
Both of the loads above with H414 powder manifested some semi-burned powder residue remaining in the chamber upon case extraction. This would cause subsequent rounds chambered to suffer tiny compression dents after being fired due to impressions made by the powder granules. Bad accuracy, bad spreads on the one load, and unburned powder tell the tale told before. That is, some ball powders don't work well in large, bell-shaped rimmed cases. Future experiments will be made with H380 ball powder when some is secured.
One other load tested:
200 gr. jacketed Nosler partition .323
46.0 gr. IMR 4350
CCI 250 mag. primer
Reworked Graf 7.62x54R cases
Avg. muz. velocity: 1558
Standard deviation: 33.93
Accuracy much better than the same bullet used with H414 powder, data above.
I should add that the temperature on this day at the range was just above freezing, but the ammunition was kept in the car at a warmer temperature until just before use.
Added 10-06:
Today I was able to steal some time to sneak off to the rifle range for a little while. Unfortunately, after I got to the range, I discovered that I left two batches of experimental lead loads at home on my workbench. Oh well, there's my work for the next trip.
On this trip today, I was able to chrono some 8x50R Austrian jacketed loads that I put together back in December, 2005, so what's the rush??!
The original military factory loads employ a 244 grain jacketed bullet. As we have discussed before, this is a bore riding bullet of .323 diameter with an obturating base to seal the propellant gases in while expelling the bullet.
Because we can't get bullets of this design for reloading, the best we can do is to come as close as possible. Last year, I was lucky enough to find a box of 100 Hornady 250 grain bullets in .338 diameter for $5. These were RN jacketed bullets with a small soft-nose tip. When run through a .329 sizing die from Lee, these sized down nicely. When finished, they weigh and look a lot like the kind of bullet originally used in this military caliber. In the sizing process, these bullets spring back to .330 final size. Since these bullets are close to true bore diameter, we don't need to concern ourselves with an obturating base for gas sealing purposes.
The powder used was H-1000, the slowest propellant Hodgdon makes. This powder was originally designed for the .270 Winchesters that were used in the 1000 yard matches. Heavier bullets like slower powders, so I figured the 250 grain bullet might go well with this powder. One fellow at the range called this heavy bullet a "bowling ball."
Data for this load:
8x50R Austrian
Hornady 250 gr. jacketed RN .338 bullet sized down to .330
50.0 gr. H-1000
Brass: RP .45-70 converted by Buffalo Arms
CCI 250 magnum primer
Average velocity: 1520 fps
Standard deviation: 17.38 fps
Ambient temperature: 45 degrees F
This load gave very nice accuracy at 50 yards. I was shooting though another member's chrono that was already set up there. I have reported on this load before, and the results are similar.
I do not recommend this for hunting, as the bullets such as I have used (converted .338 magnum) are designed for use at much higher velocities and have heavy jackets and possibly harder alloy fillers. Travelling at 8x50R velocities, they probably would not expand properly.
Added 2-3-07:
Today I was able to take the time to go to the range at a time when weather permitted setting up the chronograph.
My inclination is to concentrate on developing useful data for cast bullet loads, as proper jacketed bullet designs are just not really available at this time. Using the Lee .329 bullet mold, we can make inexpensive lead bullets that work well with this caliber.
For well over 20 years, I have been using IMR 4759 powder for reduced charges in both jacketed and lead bullet loads. Another good powder for reduced charges in large-cased centerfire cartridges is H4198 (or IMR 4198) . Two of the loads below each use one of these powders.
Cast lead bullet of nominal 205 grain weight w/ gas check
(Lee mold)
20.0 grains IMR 4759
WW primer
Modified Graf 7.62x54R case
1467 average muzzle velocity
20.79 standard deviation
Bullet prints 1 inch high @ 50 yards, very accurate
Ambient temp. 38 degrees F.
Cast lead bullet of nominal 205 grain weight w/ gas check
(Lee mold)
23.0 grains H4198
WW primer
Modified Graf 7.62x54R case
1404 average muzzle velocity
13.62 standard deviation
Bullet prints 4 inches high @ 50 yards, accurate
Ambient temp. 38 deg. F
A re-test of a previous load was conducted.
Cast lead bullet of nominal 205 grain weight w/ gas check
(Lee mold)
16.0 grains H2400
Federal 210 primers
Average muzzle velocity 1302.5
Standard deviation 36.15
Bullet impact for this load is dead center of target @ 50 yards
Note: In my test rifle, I will increase this load to 17.0 gr. of H2400, as it was noted that some cartridges leaked gas when fired; of non-leaking cartridges, the average muzzle velocity was 1331 with a standard deviation of 15.89. What this means is that I am right on the fence of having and not having enough pressure at the moment of ignition to seal the brass case to the chamber walls. The case used was a modified Graf 7.62x54R, which have fairly thin walls and should not be an unusual problem for sealing. In spite of this problem, accuracy was good.
Added: 2-10-07
Re-test of a previously tested load.
Hornady 250 grain jacketed round nose bullet, resized to .330 from .338
46.0 grains IMR 4350
CCI 250 magnum primer
Graf brass re-worked 7.62x54R to 8x50R Austrian
Average muzzle velocity 1680.5
Standard deviation 26.81 fps
Accuracy good, prints 2-3 inches low from point of aim at 50 yards
Ambient temperature 46 degrees F
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