Bill Alexander on Wolf steel case ammo

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  • stanc
    Banned
    • Apr 2011
    • 3430

    Bill Alexander on Wolf steel case ammo

    10-28-2011
    The projectile design and weight is one of the parameters we are exploring. We are looking towards the best weight for the carbines without compromising down range ability. Equally there is a trade to be made in respect to construction wrt cost, accuracy and terminal performance. Given the market for this, cost will be the driver.

    Other options are the case coating and the sealant type.

    11-25-2011
    Holidays are great for a quiet workshop to run special equipment and tests.

    Looking good so far, we have done positively horrid things to the cases to see what problems we can cause, -40F to +350F, oil and fouling. I am really beginning to anticipate doing the accuracy test, if these things continue in the same way they should be awsome. Not looking forward to the overload tests I hate firing strings of proof level loadings.

    12-12-2011 (posted on arfcom)
    Case testing is complete and went well. Now its up to the Russian factory to run the spec steel cases and load them up.

    Pending last minute changes, it will be a steel case, with a 110 grain bullet with profile similar to the 107 grain Sierra Match King. Final bullet composition will be up to Wolf and their Russian partners.

    12-31-2011
    I will try and dig out some of the pictures of the rig set ups we used. It was an interesting few weeks and as interesting to see how the rifles performed, as the ammunition.

    I was exceptionally pleased that that "sloppy" neck I put in the design actually proved itself to be a useful feature.The green lacquer quandry that it sticks cases proved to be unfounded utterly. I was always questioning why the Russians who have a propensity for fully automatic fire would ever use a case finish that was detrimental to function. Given the chamber design it was seen that the green stuff actually helped as everything got hot/cold/dirty.

    Just for Stan's notes we ran just over 2800 rounds for the initial test phase just to examine the cases. In the end we had to conclude the test as abbreviated.

    01-01-2012
    The gun was instrumented and ran up to +300 F externally measured temperature under continuous firing and also allowed to cool repetatively with a round in the chamber. We cheated a little to push the temperatures up by the use of external heating tape and a perheat for the loaded magazines . The temperature was limited by safety, the need to be able to handle the ammunition and magazines and the magazine followers melting out. It remained a problem to maintain weapon lubrication at these temperatures. Fully automatic fire was not shown to be a problem.

    While it is possible to acheive higher temperatures during extreme use in high solar loadings it is also extremely rare and is frequently accompanied by weapon failure.

    03-03-2012
    I know it looks painfully slow but the project is actually moving along quickly (a relative term in respect to the usual timeline for a military style complex to respond). We have a formal order for a slew of test rifles and the pressure test equipment has already been produced and is at the factory in Russia. The initial report and test work we performed validated the cartridge design for their engineering division and actually laid to rest some nervousness about the configuration. Remember there were rumors that the Russians had already tried this route. They actually did and met with some problems because of the way they designed the cases. Next week we are due to meet with them again and discuss the progress. We will probably cover the propellent types as well as the performance specifications. Primer sensitivity will need the specification to be confirmed and accuracy requirements will be a big topic.

    I doubt that any of the distributors will even acknowledge the ammunition much yet take pre-orders until Wolf takes possession of the first shipments

    03-20-2012
    Slow but unerring!

    Back from IWA, nice talks with the head of engineering and also the Molot rifle folks. Russians are a breath of fresh air wrt engineering and will examine and calculate every detail. We spent considerable time looking at the hoop strain of the AR breach and the allowable elastic deformation of the cases. The AR is marginal in 5.56 with steel cases dues to pressure but the Grendel is a better prospect. They are cautious regarding the backing support of the barrel extension but allowed us the benefit of experience in this matter. Such talks leaves one wondering how some of the cheaper AR parts will effect the system and the things that people have seen with the 5.56 steel cases.

    It does mean that we were correct to insist on the 50,000 psi loading and not allow this to climb just to get Mv to make sales.

    Saw the first 6.5 Grendel AK or correctly 6.5x39 Grendel. Sporter set up with a 10 round magazine but a magnificent gun. I intend to buy one.

    03-20-2012
    The neck will be somewhat variable because of the lacquer coating. It will however be functional in the Grendel chamber within the prescribed manufacturing tolerances.. This also allows for the crimping procedure and the neck sealant.

    Batch to batch variations are included within this specification.

    11-09-2012
    Got 10,000 rounds!

    Answers arrived about 30 minutes ago. Slow I know, feel all your pain. Try sitting where I am!

    11-18-2012
    Yes, the Russians have finalized the projectile design and also the powder.

    Powder is to be a derivative of the type sold by Western Powders and is extremely stable, especially in the cold. It is a double base ball type and will be loaded to 3550 bar in line with the existing weapon and ammunition set up. The cases are now set to use a small primer and will use a boxer design rather than the berdan we originally tested. This simplifies compatibility with the less enthusiastic fire control group in the AR while at the same time allows the ammunition to work with the AK without problems related to primer failure.

    The projectile closely follows the design of the 7n6 5.45x39.5 in that it is a boat tail design with an internal cavity in the projectile nose. Constraints on the length of the projectile restrained the weight to 100 grains as we transitioned from a lead core to a steel core. This is lighter than we initially proposed but the combination of bullet weight and powder will provide a fast low recoil combination for the carbines. Ogive is 10 diameters and the boat tail is 9 degrees which is optimum, I anticipate the Bc to be around 0.390 but this is an estimate.

    A heavy type ball is also being examined for a longer range type weapon.

    06-27-2014
    The fill follows military requirements for 78% or thereabouts. The photograph is representative but glue and model powder does not always behave. The air space helps buffer the shifts in pressure due to temperature. Alternatively one can use a 100%-104% fill and let the thermal expansion of the powder reduce the available surface area but this will only work with certain powders. For high speed loading machines, powder must be selected that is conducive to the metering system and also the rapid motion. It has to provide consistency in the finished product regardless of slight variations in the charge weight. Most importantly the powder itself must have repetitive characteristics batch to batch and be readily available.

    For a service cartridge there are a number of additional requirements that have to be satisfied. Among these are deviation of performance over time due to chemical instabilities. This will drive both the form and the type of propellant.

    The load pressure is in accordance with SAAMI with the typical loaded round presenting 49,000 to 50,000 psi as sampled at STP on a new batch.

    One should finally consider the controllability of the parent platform under fully automatic use in deriving the charge weight and final velocity, noting that a contribution of 1/3 charge weight is directly attributable to recoil at the muzzle velocity

    06-30-2014
    Five years this has taken. Does anyone realize how complicated it is to just test the case coating. Then there is the balance of recoil vs velocity vs bullet weight. What is the intended application. Powder selection must balance the bolt speed for both long and short weapons. The round has to match up with the rest of the offerings. A bullet that throws a foot from everything else is worthless. It has to do this in the hot, cold, wet and dry. Bullet construction is another life sentence.

    We ran coral sand in the system to check extraction. The gun was recalculated at least three times that I know of. We debated the support available in the chamber for three hours at the IWA show with two translators and the Izhmash designers

    07-15-2014
    The green lacquer coating proved to be superior in the testing of this caliber. This is not to say it is always the case but with the length to diameter ratio of the cartridge and also the operating pressures we saw marked improvements in feed and extraction with the green lacquer over all other coatings. In abrasive contamination tests we used black coral sand as well as platelet desert wind blown sand to evaluate the behavior and would note that the feed and extraction was in some instances better than the control brass cased ammunition.

    The projectile design was evolved over a period of time to create a yaw cycle that would be tolerant to intermediate barriers and also body extremities. The driving design requirement was to make sure it was adequate to take game in the class of feral hogs. It should be noted that the yaw cycle can be shortened or extended with simple design manipulations

    Projectile weight was balanced against recoil and velocity specifically from shorter barrel weapons while ensuring the pressure point at the port would support reliable operation.
    Last edited by stanc; 08-24-2014, 02:27 PM.
  • Variable
    Chieftain
    • Mar 2011
    • 2403

    #2
    Wow Stan! The search-fu is strong in you grasshopper.

    Thanks for consolidating all that very useful info in one place.
    Life member NRA, SAF, GOA, WVSRPA (and VFW). Also member WVCDL. Join NOW!!!!!
    We either hang together on this, or we'll certainly HANG separately.....

    Comment

    • stanc
      Banned
      • Apr 2011
      • 3430

      #3
      You're quite welcome, Chris. I found it kinda interesting to do, anyway.

      Besides, there was nothing on TV worth watching at that hour, and it was too early to go to bed...

      Comment

      • Smokepole50

        #4
        Wow...............is this bullet going to be just like the 5.45 7N6 bullet? It sounds like it if I read Bills post correctly. That will be some wicked ammo if it is built the same way. Great work Stanc!!

        Comment

        • Variable
          Chieftain
          • Mar 2011
          • 2403

          #5
          Originally posted by Smokepole50 View Post
          Wow...............is this bullet going to be just like the 5.45 7N6 bullet? It sounds like it if I read Bills post correctly. That will be some wicked ammo if it is built the same way. Great work Stanc!!
          Well, not exactly. We jumped to conclusions before, and thought that's it'd just be a scaled up 7n6 with the steel penetrator and all. But we were wrong it appears. The cross sections show a core with only lead and a copper washed steel jacket.

          Bill A. wrote--- "The projectile closely follows the design of the 7n6 5.45x39.5 in that it is a boat tail design with an internal cavity in the projectile nose. Constraints on the length of the projectile restrained the weight to 100 grains as we transitioned from a lead core to a steel core."

          We did get the boat tail and the nose cavity. When he wrote steel core, I think he meant to type steel jacket instead of core. I could be wrong, and maybe something else changed it along the way, but that's what I think happened. Maybe he'll post some clarification if I'm wrong. No matter what I'll likely be happy.

          The flip side of this is that while I would have absolutely went nuts for the steel penetrator to have been included, it's probably a good thing they didn't. 5.45 7n6 surplus ammo imports were recently squashed by the ATF, and I doubt they'd let a 6.5 version in. It would have been realllllyyyy interesting to see how it'd penetrate, but I highly doubt we'd have seen any of it.
          Life member NRA, SAF, GOA, WVSRPA (and VFW). Also member WVCDL. Join NOW!!!!!
          We either hang together on this, or we'll certainly HANG separately.....

          Comment

          • Bill Alexander

            #6
            Wow how time flies when you are having fun!

            Comment

            • Keep The Change
              Warrior
              • Mar 2013
              • 590

              #7
              Thanks Stan for the consolidation of the Bill quotes.
              Thanks Bill for your diligence and hands on work in helping develop this cartridge, and thanks for working hard to meet the needs of the Grendel hoard.
              It gives me a lot more confidence in shooting this cartridge from Wolf knowing the amount of input and testing you put into it.

              Comment

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