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    • #28928
      goody
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      One of my favorite rifles is a mauser sporter I found long ago in a pawn shop. It is a 8mm 318 bore octagon barrel on a 98 military action and it has the gunsmiths name on it. Ok, it shoots cast from 32 winny and 8mm -323 boolits with precision. I swag down Hornady FTX 32-160 gr jacketed bullets with boring precision also. I am in the recommended pressures of 35,000 psi and I want to see what more I can get. My question is, when shooting large cast or the swaged jacketed (still large) for bore can I trust the old primer flatten or sticky extraction as my over the top load? I don’t want to magnamize this gun simply get what it will give for what it is. Larry Gibson have you messed with any of these? Thanks for input if based on experience. The action is from the thirties and it is very clean almost new bore even though it was made about 120 years ago! Ludwigs Mauser Bolt Rifles book gives 42,660 psi with a 157 jacket bullet at 2745 fps. I am sure that is with .318 bullets.

    • #28944
      Goodsteel
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      I believe Larry is on vacation with no internet (must be rough being retired LOL!).

      In my totally humble, non-biased, not so humbly given opinion, I’d say use federal primers if you can get them, and yes, work up carefully.
      One of the things I think you should be watching for is loose primer pockets.
      With old rifles with sloppy chambers, I’ve sometimes found a spot where the pressure was safe, the load was accurate, but after a few firings, I could feel the primers going into the pockets easier than when I started. If you watch for flattened primers, that’s usually a good indication because the primer is thinner and softer than the brass its seated in. But using Wolf or S&B primers for this is a fools errand, and remember, just because you find a load that didn’t burst your chamber during testing, doesn’t mean it can take repeated abuse from a super stout load. (How many times do you bend a paper clip before it breaks?)

      We all wish these things were black and white, but the truth is, there is a lot of grey area here. Your rifle will probably take far more pressure than a sane person would put to it, but general guidelines based on the material strengths of the mechanism you are tuning are as follows:
      Your barrel must be strong enough to contain the pressure of the cartridge inside it without bursting.
      Your brass must be strong enough to contain the pressure inside it without flowing.
      Your primer must be strong enough to contain the pressure in front of it, without flowing back into the firing pin hole, or allowing gasses to escape around it.

      So everybody says “ah don’t want to blow ma gun up with these here reloads”.
      That’s an excellent plan, and I agree wholeheartedly, but there’s a whole lot of things that are going to have to happen before that occurs, and how quickly they happen, and whether or not you see them depends completely on how carefully you work up your loads, and how observant you are in the process.

      For instance, I just worked up a load for my 357 black hawk. This was to be a last resort defense load for bear. I was using the RCBS 35-200-FN cast fairly soft (14BHN) and loaded to the crimp groove in 38special cases.
      The object was to see how hot I could run them before the brass started to flow and extraction became sticky, and the CCI primers had to hold up too.
      Well, my old Lyman book had a load for a 190 grain slug in 357 magnum. Top load listed for 2400 was 11grains. I started working up from the minimum to the maximum and shooting over a chronograph to see how this load played with the book data. Speeds were actually spot on, and the full 11grains gave me 1050FPS just like the book predicted.
      So from there, I started creeping forward making stronger and stronger loads, always two at a time. I fired two over the Chrony, recorded it in my book, then pushed the brass out and looked carefully at the primers.
      Then I would reload, and mind the pressure required to seat the primers.
      I ended up at 15.8 grains of 2400. It was at this point that there was no more room to compress the powder any more, the primers were flat and starting to flow a little (surprisingly, they still require the same seating pressure) and the brass was slightly hard to extract, and showed the tooling marks of the inside of the cylinder. Speed was between 1390 and 1410 FPS. (this load is safe in my pistol only!!!)
      So now I have a last ditch, shoot the bear and set him on fire in the process, defense load.

      Whether we’re talking about a rifle or a pistol, the question of what your firearm can take is not as black and white as you might think. There is a margin of error built into all firearms that are safe to shoot. If you want to load up hot loads, and drift into the margin a little, do so cautiously, and remember that performance always has a price tag. Also remember that every catastrophe in human history was preceded by warning signs that were ignored by those inevitable recipients of the Darwin award.

      With the rifle in the OP, I would pick a reasonable speed as a target, pick a reasonable powder to get me there, and work up carefully. a good load will be stout, but not punishing. It will be accurate, and when you reload, you will fully expect to get at least 7-8 reloads out of your brass. You will not have any trouble extracting the brass from the gun, there will be zero gas leakage around the primer, and there will be almost no marks left on the brass from the chamber. When you start to notice these nice things slipping away two by two, you know you need to back up a little.

    • #28948
      goody
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      Thanks, I am presently at glorified 30-30 performance and that is fine but I want to sneak up closer to 300 sav stats. I am no hotrodder so I will precede with caution!

    • #28961
      seaboltm
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      Goodsteel, curious about lead that soft with velocities that high: did you get any leading at all?

    • #28967
      goody
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      This experiment is for jacketed bullets only. With the 32-horn ftx swagged down I only got to 40 gr of H4350. They mushroomed perfect at 70 yards so I stayed with that load and it is slow. With the rcbs 32-170 I stopped at 19 gr of 2400. The FTX bullets require 30-06 military brass for the thicker neck. The gun was chambered with a .323 chamber which I read was common at that time in Europe. As you can see I am slow but safe and want to get more oomphf out of this gun.

    • #28968
      Goodsteel
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      Of course. But the object was to get six shots on a rapidly closing target that plans to eat me, so I figured since the group size would be increasing far slower than the size of the target, it wouldn’t be much of a concern. LOL!
      Still, from a clean gun, I was able to place all six where I wanted them, and accuracy didn’t really start to deteriorate noticeably till the 10th-12th shot.
      Those were loads intended for a very specific purpose, and I only brought it up here by way of demonstrating how to safely work up to your goals without getting hurt, or ruining the firearm.

    • #28969
      seaboltm
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      I have an 8×60 with the 318 bore. I thought about swaging bullets, but there seems to be a good supply of .318 bullets available. But of course they are pricey. Can’t wait to see more results.

    • #28970
      Goodsteel
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      I watched Lar45 swage a few jacketed bullets for his 9.3X57. Lube is a must, but he got it done, and accuracy was on par with the rifles capability.

    • #28984
      goody
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      8×60, that puppy can bark! I don’t mind mind cranking up a load when fit is correct but I do get wheezy knowing the bullet is a little tight in the bore!

    • #28986
      Larry Gibson
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      A bullet is swaged down in the first bearing length of travel in the bore. I have pressure tested .310 – .312 bullets with copper annd soft steel copper washed jackets in a .308W with .308 barrel. A slight pressure increase was measured sometimes at the beginning of the pressure rise when the psi was low. The MAP with the oversize bullets was often very close to the MAP with the same weight .308 bullets ant the same load.

      I did measure excessive pressures when steel jacketed AP bullets with penetrator core and with heavy for caliber copper jacketed bullets with long bearing surfaces were tested.

      I have several times pressure tested 160 – 220 gr cast bullets of COWW, #2 and linotype alloys with the same bullet sized .308 thru .314 in .001 increments. I could measure no meaningful difference in psi between the various sizes with the same load.

      Your M98 action should easily handle psi’s in the 55 – 62,000 regardless of the cartridge. The psi of the 8x57J is held down in deference to the M88 Commission action (not a Mauser design) and can be loaded to higher yet safe psi’s in your M98.

      Larry Gibson

    • #28988
      goody
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      Thanks Larry, I always felt confident from your input when I was in personal(lack of expierence) gray areas. I will charge forward, right after a cool front comes thru. My shop is HOT and its in the shade.

    • #28994
      Larry Gibson
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      Just use starting loads for the cartridge and work using standard MANUAL recommended (we do see a lot of bizarre recommendations on some forums) loading practices you are using. If your cases are fire formed an just NS’d flatness of the fired primer along with bolt lift can be good indicators of high psi if standard Rem, CCIand WLR primers are used. As goodsteel mentioned the harder primers intended for milsurp ammo can give a false reading. I would not exceed the max load data in Lyman’s 49th manual for the 8×57 minus 5% with matching bullet weights for the larger diameter bullets in your .318 bore. Of course start loaw and work up to those max – 5% loads.

      Larry Gibson

    • #29031
      uber7mm
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      Goody,

      Any photos of your rifle? I bet she’s a beauty!

    • #29061
      uber7mm
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      Classic! Very beautiful.

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