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Thread: My quest for the "perfect" cast .223 load for my AR-15

  1. #41
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    Larry Gibson's Avatar
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    BHuij

    So this mostly matches what I understood about twist. Namely that an uneven, rough, wrinkly, or otherwise defective boolit will destabilize at a much lower RPM than a smooth and even one. However, I also understand that boolit length/weight, diameter, and alloy (or more directly, hardness) has a lot to do with the RPM at which the projectile is most stable. For example, a 77 grain projectile (which is inherently longer than a 55 grain projectile) will need a faster spin to enter the "stable" zone, as well as a faster spin to exceed the "stable" zone and lose its accuracy.

    Your understanding about twist and RPM is incorrect. An "uneven, rough, wrinkly, or otherwise defective boolit" will not destabilize, "at a much lower RPM than a smooth and even one", any bullet not even a cast bullet. If the bullet has sufficient RPM for stabilization it will be and will remain stable regardless of the bore condition. Also, there is no "stable zone" once the bullet is stable it remains stable. Over spinning a bullet does not cause it to lose stability. Over spinning a bullet with any imbalance can and does cause it to lose accuracy by causing the bullet to delineate from its intended flight path. The farther the range the greater that delineation will be.

    The RPM required for stabilization and the adverse affect the centrifugal force has on imbalances in the bullet caused by RPM are two completely different things and affect the bullet in two completely different ways. As mentioned, a perfect bullet coming out of the bore stabilized will shoot very accurately, basically into one hole shot after shot. The trick is casting and getting that bullet out of the bore perfectly balanced. That is what match shooters, particularly bench rest shooters including cast bullet bench rest shooters, strive fore.....with both cast and jacketed bullets......it is their holy grail. As I said, once the bullet is stable it will remain stable across most if not all of it's flight path.

    That leaves the centrifugal force aspect of RPM that is causing the larger group sizes.

    Now, that being said, there have been numerous threads regarding the adverse affect RPM can have on bullets, especially cast bullets, at certain levels of RPM. No need to rehash that here but it is suffice to say that you are actually seeing the affects RPM is having on your bullets, i.e. the large groups. If you really want to find a useable cast bullet load for your 9" twist AR that will consistently group into 2 to 4 moa with the 55 gr cast bullet you are using then I suggest you use an easily ignited powder such as H322, RL 7, 3031 or H4895 that, when used with a Dacron filler, will function the action reliably while maintaining a velocity in the 1850 to possibly 2250 fps range. You can choose to not believe what I just said but unless you can cast perfectly balanced bullets and then get them out the end of the ARs barrel perfectly balanced you will find it so........because you already have.

    Let me add when I say "consistently group" I am not talking about a single 3 or 5 shot group at 50 or even 100 yards. I am talking about at least several magazines full over a days shooting, especially with an AR. Being able to shoot a 3 or 5 shot group with any bullet means nothing to me with an AR. The AR and its ammunition must prove reliable and consistently accurate for many rounds or it is useless, at least to me anyway. I am also talking about shooting to at least 200 yards if not 300 yards with a cast bullet "practice load". However, if you are interested in only 50 or 100 yard max range, as many are with such loads, then you can boost the velocity to 2400+ fps and maintain 3 - 5 moa accuracy over several magazines full of such a load. However, you must cast and load a more perfect bullet even then.
    Last edited by Larry Gibson; 02-20-2018 at 07:09 PM.
    Larry Gibson

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  2. #42
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    Quote Originally Posted by Larry Gibson View Post
    BHuij

    The RPM required for stabilization and the adverse affect the centrifugal force has on imbalances in the bullet caused by RPM are two completely different things and affect the bullet in two completely different ways.
    So I have always thought that the accuracy loss at too-high RPMs was a result of the boolit destabilizing. It sounds like I was basically attributing cause and effect improperly. The boolit will not destabilize when spun too fast, but accuracy is still adversely affected by having too high of an RPM. Thank you for the clarification.

    Quote Originally Posted by Larry Gibson View Post
    If you really want to find a useable cast bullet load for your 9" twist AR that will consistently group into 2 to 4 moa with the 55 gr cast bullet you are using then I suggest you use an easily ignited powder such as H322, RL 7, 3031 or H4895 that, when used with a Dacron filler, will function the action reliably while maintaining a velocity in the 1850 to possibly 2250 fps range.
    The part about hitting a velocity from 1850 to 2250 lines up perfectly with what my research told me before I ever dropped a single .223 boolit from the mold, and has been confirmed so far in my testing (the most accurate loads have been just north of 2000 FPS for me). In fact, one of the IMR 4227 groups in that velocity range from my first test was hitting 4 MOA, it just unfortunately wasn't cycling the action.

    I am intrigued about needing an easily ignited powder to ensure accuracy. Is H335 not considered easily ignited? I didn't have any failures to fire out of 100 rounds with the powder in my last test. Do you believe it's possible to reach 2 MOA consistently using H335, or do you think I will need to change powders to achieve that level of accuracy?

    Once again, many thanks for taking the time to answer my incessant questions and educate me. It's cast boolit vets like you who make this forum as awesome as it is.
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  3. #43
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    [QUOTE=BHuij;4296613]So I have always thought that the accuracy loss at too-high RPMs was a result of the boolit destabilizing. It sounds like I was basically attributing cause and effect improperly. The boolit will not destabilize when spun too fast, but accuracy is still adversely affected by having too high of an RPM. Thank you for the clarification.

    ....and this is where the arguments are BHuij. It takes an astronomically high rpm to adversely affect the bullets accuracy. Brian Litz spoke about this, but most here don't want to believe. He's a ballistics engineer, currently designing Berger's bullets.
    You won't have to worry about that with your AR15 with it's 9 twist, not even if it were a 7 twist. Just pm and ask Runfiverun about it.

  4. #44
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    Quote Originally Posted by vzerone View Post
    ....and this is where the arguments are BHuij. It takes an astronomically high rpm to adversely affect the bullets accuracy.
    I want to make sure I'm understanding you correctly--

    Do you mean to say it takes an astronomically high RPM to adversely affect a theoretically perfectly balanced boolit's accuracy? That I can believe no problem. If you're saying it takes an astronomically high RPM to adversely affect the accuracy of my crappy wrinkled excuse for a boolit, then I'm confused. My accuracy loss thus far, which is clearly observable once I go much above about ~2100 FPS, is not due to an overabundance of spin for the specific projectile I'm using, but some other factor entirely?

    In other words, if my boolits are not accurate, it's not because they're spinning too fast, it's because they're unbalanced. High RPMs might magnify the effect of having an unbalanced projectile, throwing off the accuracy more and more as RPM gets higher and higher. But the RPM is not the root issue, it is only making the pre-existing effect of an unbalanced projectile worse. Even if I could cut the RPMs in half (theoretically shooting the boolit at ~1000 FPS) the accuracy wouldn't be any better, because the boolit is too fundamentally flawed to shoot at 2 MOA at any speed (never mind that it might not fully stabilize at 1000 FPS). Correct?

    If this is what you're saying, that makes sense to me, but as no projectile actually reaches the theoretical level of "perfectly balanced," it seems like I can more or less safely assume that my projectiles will at some point spin too fast to reach the accuracy goal I'm trying to hit (2 MOA in my case). If I had a perfectly balanced projectile, I could spin it as fast as I wanted and still have accuracy. Since I don't, there is a practical upper limit to how fast I can spin my projectile and still expect good accuracy. With the boolits I am currently using, I can observe that the best accuracy thus far is obtained at about ~2050 FPS. A little math tells me that RPM at that velocity is 164,000. If I had a more perfect boolit, I could probably obtain even better accuracy even at higher RPMs (and therefore higher velocities).

    Some people (like Runfiverun) have gotten so good at making really well-balanced .223 boolits that they can run them at 2700 FPS through a 1:7 barrel and still get good accuracy, which is awesome. I never would have suspected that a cast 55 grain boolit could be accurate at 243,000 RPM. And increasing the quality and balance of my boolits is a really good goal and a really good way to increase accuracy. But as things sit right now, with the boolits I've been making, and my 1:9 barrel, I seem to be doing best right around 2050 FPS, when I push it faster, the RPMs affecting my imperfect boolits are compromising their accuracy to the point that I no longer consider the results "good enough" for my goals.

    Please correct if I am wrong. I'm concerned that my replies seem argumentative or skeptical; that is not my intention. I just want to learn and understand, and it seems I've hit a very complex and controversial area of the science of reloading, which is rife with misinformation and misunderstanding
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  5. #45
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    BHuij

    First let me say this about H335 in the .223/5.56 cartridge; H335 has been my "go to" powder for use with 45 to 55 gr jacketed bullets since the mid '70s. I have shot many pounds of it up in such loads in Bolt actions SSs and gas guns. However, when it comes to cast bullet use in the .223/5.56 I have not found H335 to work well with those cast bullets of 60 gr or lighter. All powders may ignite (some more easily than others) but many, H335 included do not burn efficiently until a certain level of pressure is achieved within a certain time span. In the 223/5/56 cartridge with a 60 gr or less cast bullet by the time a load is developed that reaches uniform burning pressures the velocity/RPM is too high.

    The powders mentioned in my previous post ignite easily and burn efficiently at a lower pressure than does H335, especially in the .223/5.56 with cast bullets. Those powders will also develop enough gas port pressure to function the action while keeping the velocity/RPM down at a manageable level for some accuracy. With cast bullets many times what powder we want to use isn't going to be the best to use or the powder that works. With heavier cast bullets than 60 gr H335 does seem to hit it's efficient burning pressure level sometimes. Thus to answer your question; no, I do not think you will get consistent 2 moa accuracy with H335 under your 55 gr cast bullet. Yes, you should look to a more easily ignited powder that then burns efficiently, functions the AR action while keeping the velocity/RPM down at a manageable level.

    Your basic concept of RPM as reiterated in your last post is essentially correct. There is an RPM Threshold with all bullets. The better balanced the bullet is, cast or jacketed, that it exits the muzzle at the higher that threshold will be. Under the RPM Threshold the bullets will behave in a normal fashion and follow the intended and exhibit normal linear dispersion as the range increases. However, when the bullet exceeds its threshold it departs at a tangent from the intended flight path (trajectory) or in a long helical spiral around that flight path (trajectory) that exceeds normal linear dispersion. The longer the range the greater that non linear travel will be from the intended flight path (trajectory). That is when/where flyers come from or when the total groups accuracy really goes south. Even then you may note that the bullet holes in the target are still round. That indicates then went point forward through the target meaning the bullets were still stable even if totally inaccurate.

    With your 9" twist barrel your best accuracy with the 55 cast bullet you're using would be down under 1900 fps. However, that may or may not function the AR action reliably. Given the heat treatment and PCing you do to the bullet you should be able to push the velocity/RPM up to at least reliable functioning and maintain accuracy at least consistent with what U.S. made M193 ball. That probably will be in the 2 - 3 moa range for consistent accuracy over numerous rounds. You might find a bit heavier cast bullet of 70 or 75 gr to work better in your AR.
    Larry Gibson

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  6. #46
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    BHuig

    Read what the ballistic engineer Brian Litz wrote about how much that excess spin affects your bullets accurazy at 1000 yards.

    Bryan Litz says:
    July 25, 2013 at 7:24 am
    For practical purposes, the answer is FALSE
    As a bullet arcs on a long range trajectory, it’s axis is torqued (by aerodynamic forces) to constantly align with the oncoming airflow. When a spinning object has its axis torqued, the object reacts by pointing its axis primarily ‘out of plane'; 90 degrees from the applied force. This results in a nose-right orientation (for right twist barrels) known as the yaw of repose. The yaw of repose steers the bullet ever so slightly to the side resulting in gyroscopic (spin) drift.
    The bullet nose will point slightly above its velocity vector (pitch), but that pitch is only about 1/10 of the yaw of repose which is not enough to cause a practical vertical drift (less than 1/2″ at 1000 yards). Typical yaw of repose remains below 1/60th of one degree, while pitch is on the order of 1/600th of one degree. This small amount of pitch and yaw is not enough to induce a measurable amount of additional drag, even for highly stabilized bullets.
    All of the above applies to stable projectiles in supersonic flight on ‘flat fire’ trajectories. For projectiles fired at high angles (above ~10-20 degrees above the line of sight), it is possible for the bullet to not track, or trace with the trajectory. This is a common design challenge for artillery shells that are often fired on high angle trajectories. The axis of the spinning shell may be too rigid to bend with the exaggerated trajectory. In that case the shell can ‘belly flop’, or fall base first. However for small arms projectiles on flat-fire trajectories, this isn’t a problem.

    Another consideration with spinning a bullet too fast is related to bullet failure. This discussion assumes the bullet remains structurally in tact.

    Dynamic instability during transonic flight is also a different problem, not related to the above discussion.

    Now for the H335 I've never used it for cast in the .224 calibers only for jacketed along with lots of surplus 844 and WW748 which all three are very very close to one another. I have used it in larger calibers with great success.

    You should try weighing some of your bullets and see how much weight variance you have. If it's more then .1 to .3 then you need to work on your casting...all avenues of it.

    I've shot culled bullets that had wrinkles, creases, etc. in them just for the heck of it and they actually shoot better then one would think. I know a lot of guys that do it. Most important thing is getting the bullet started straight. Your 2 MOA is more then doable even with your 9 twist at the higher rpm range you mentioned. Remember when I told you that a chromed bore isn't a cast bullets friend? Ask Runfiverun about that too, tell him I told you too.

  7. #47
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    Thanks everyone for the info. Larry, I read some of your posts on other threads elsewhere on this forum and found a few places where you mentioned ideal RPM for cast boolits to be somewhere in the range of 125,000-140,000. I assume this is the basis of your statement that best accuracy with my 1:9 barrel would probably be achieved at under 1900 FPS, as I would have to get down to about 1700 or 1750 FPS to hit those RPMs. Even if H335 would cycle my action at those low speeds, the burn at that pressure would be so inconsistent that it would cause its own set of problems with accuracy. I estimate I would have to drop the charge down to about 16.5 grains to arrive in the ideal RPM threshold you describe, which is a full grain less than the lowest load I have tested so far. Highly unlikely to reliably cycle my action. So it sounds like I may need to delegate the rest of my pound of H335 to be used in a larger caliber like 7.62x54R where I can much more easily reach the pressures required for a clean and consistent burn.

    You have recommended a handful of other powders that burn cleaner at lower pressures and would probably allow me to get closer to, if not directly into, the 125,000-140,000 RPM range without compromising my reliability: H4895, H322, Reloader #7, or IMR 3031. I think that, unless my next set of tests gets me into the 2 MOA range, I will take your advice and buy one of these powders. I would lean towards H4895 just because I am most familiar with it out of the 4 you mentioned, but do you have a recommendation for which one would be best? Ideally one that meters well--I'm seeing that people using H4895 and especially IMR 3031 struggle with metering.

    Vzerone, I have a pretty long checklist of quality control items to implement for my boolits. While I don't know that I'll be weight sorting every time, I am definitely interested to at least check my cavities against each other so I can be aware if there are major consistent weight variances between cavities. I suspect though, that if I can get my boolits shaped consistently, all having good fill out and flat bases, then any weight variances would be more of a difference maker if I was trying to hit sub-MOA with these instead of 2 MOA. The fact that I was able to hit 4 MOA using boolits with voids, poorly-applied powder coat, and, apparently, inconsistent powder burn, as well as being probably in the neighborhood of 164,000 RPM (well above what Larry indicates is optimal) AND with zero case prep in mixed range brass... I suspect I will be able to get to 2 MOA by fixing the higher return-on-investment problems here, and am optimistic that I won't have to weight sort all of my projectiles in the long run for plinking ammo.

    If/when I get a heavier mold for longer range and more precision shooting, weight sorting as a matter of course makes lots of sense.

    Thanks again all. You have provided some fantastic information for me to digest and work into the procedures for subsequent tests while I chase down the accuracy I want.
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  8. #48
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    Forget that rpm thing. The velocity you picked as the most accurate pretty well may not be. To say it wouldn't shoot more accurate at a higher velocity is just not true.

  9. #49
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    Quote Originally Posted by Larry Gibson View Post
    I have not found H335 to work well with those cast bullets of 60 gr or lighter. All powders may ignite (some more easily than others) but many, H335 included do not burn efficiently until a certain level of pressure is achieved within a certain time span. In the 223/5/56 cartridge with a 60 gr or less cast bullet by the time a load is developed that reaches uniform burning pressures the velocity/RPM is too high.
    My first test loads were loaded to an OAL of 2.060, my next set of tests (the first ones with H335) were loaded to an OAL of 2.075. I realize this is a fairly minuscule change, but .223 isn't a particularly large casing, so even a small change could theoretically have a significant effect on pressure.

    My question is, if I shorten the OAL somewhat to increase pressures, will the resulting increase in burn consistency be a bigger factor for improving accuracy than the loss suffered by not seating as close to the lands?
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  10. #50
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    It sucks when you get two opinions that appear to be different wrt RPM effects.

    I would lean more towards what Mr Gibson is recommending. I offer a KISS example...

    Consider a car tire and how large and massive it is. Yet, to balance that tire, weights as low as 1/2 oz are used to remove vibrations. Running a slightly out of balance tire at 25 mph may not even be noticed. Take the speed to 70 mph and things change.

    If you have a well balanced tire, (jacketed bullet), it will run smoothly (accurately) at a wide range of speeds (RPM). A tire that is not balanced (cast bullet with imperfections) may be serviceable at lower speeds but not acceptable at higher speeds.

    Cast bullets do NOT equal the consistency of jacketed. Visual inspection and weight sorting will cull the worst out, but even with that, they fall short of jacketed bullets.

    You are dealing with a very light bullet. A +/- .2 variation resulting from the bullet dropping at a different weight from a different cavity is not going to matter much, if the bullet is concentric. That same variation caused by a void near the surface or a wrinkle will matter.

    I doubt you will achieve your goal without at least closely inspecting your bullets before coating them, and again after the GC is applied. And it may be necessary to weigh them.
    Last edited by dverna; 02-22-2018 at 12:01 AM.
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  11. #51
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    BHuij

    My first test loads were loaded to an OAL of 2.060, my next set of tests (the first ones with H335) were loaded to an OAL of 2.075. I realize this is a fairly minuscule change, but .223 isn't a particularly large casing, so even a small change could theoretically have a significant effect on pressure. My question is, if I shorten the OAL somewhat to increase pressures, will the resulting increase in burn consistency be a bigger factor for improving accuracy than the loss suffered by not seating as close to the lands?

    I have measured the pressure in thousands of cast bullets loads in many different cartridges including the 223/5.56. You will not be able to shorten the OAL enough to make any difference. Any difference would probably require multiple 10 shot pressure tests of each OAL. Then I doubt any difference in the measured average pressure would still fall within ES of either OAL tested. Lots of theories out there but many don't pan out. Yes in many instances seating a bullet deeper can and does raise the pressure. However given the nature of H335, the case capacity of the 223/5.56 case and the minimal amount you can seat the bullet deeper a sufficient increase in pressure just isn't going to happen.

    Your best bet is to switch to a powder I suggested, start low and work up to reliable functioning. That will be where your best accuracy will be in the AR with a cast bullet load that still functions the action. It still may not meet your accuracy requirement but since you are hardening and PCing the bullets you won't know until you try.

    dverna's "KISS example" is valid.
    Larry Gibson

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  12. #52
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    Quote Originally Posted by dverna View Post
    BH

    It sucks when you get two opinions that appear to be different wrt RPM effects.

    I would lean more towards what Mr Gibson is recommending. I offer a KISS example...

    Consider a car tire and how large and massive it is. Yet, to balance that tire, weights as low as 1/2 oz are used to remove vibrations. Running a slightly out of balance tire at 25 mph may not even be noticed. Take the speed to 70 mph and things change.

    If you have a well balanced tire, (jacketed bullet), it will run smoothly (accurately) at a wide range of speeds (RPM). A tire that is not balanced (cast bullet with imperfections) may be serviceable at lower speeds but not acceptable at higher speeds.

    Cast bullets do equal the consistency of jacketed. Visual inspection and weight sorting will cull the worst out, but even with that, they fall short of jacketed bullets.

    You are dealing with a very light bullet. A +/- .2 variation resulting from the bullet dropping at a different weight from a different cavity is not going to matter much, if the bullet is concentric. That same variation caused by a void near the surface or a wrinkle will matter.

    I doubt you will achieve your goal without at least closely inspecting your bullets before coating them, and again after the GC is applied. And it may be necessary to weigh them.
    Thank you for the input and example. It seems like the heart of the disagreement is one party says "no cast boolit will ever be balanced enough to spin faster than 140,000 RPM without compromising accuracy" while the other party says "if you're really careful with your cast boolit making, you can spin them as fast as you would ever need to (i.e. much faster than 140,000 RPM), so make really good boolits and you'll never have to worry about RPMs messing up your accuracy."

    I think everyone's in agreement that there is actually an upper limit to how fast you can spin a boolit and still have good accuracy. Just seems like we can't agree on where it is. Either it's at 140k, or it's so much higher than 140k that we don't need to worry about it... again, provided we're making really good quality boolits, and getting them through the chamber, throat, into the bore, and out the crown as straight as possible.

    As for me, I'll do my own testing to determine if I'm capable of making boolits good enough to spin faster than 140k RPM and still hit my intended target accuracy of 2 MOA. I am optimistic that this is actually possible. I have reached 4 MOA with no case prep, using crappy, crappy boolits with voids and wrinkles, uneven powder coat, and mashed gas checks that messed up the flat base of the entire boolit. These projectiles fired at an approximate RPM of 164,000.

    There are so many things that can mess up my boolit's balance (bad casting practice, weight variations, bad powder coat, bad gas checks, case necks swaging the boolit when seating, seating crooked, crimping too much, crimping too little, too tight of a throat in the rifle, boolit deformation due to chamber pressure, I could go on and on), that I won't be surprised if I do find a practical upper limit on my RPMs at some point during the testing. But indications thus far are that I can get at least reasonable accuracy already at 164k, so I think by improving my boolit and cartridge quality as dramatically as I am, I can probably reach my modest goal of 2 MOA @ 100 yards out of my rifle using this mold and this powder, and hopefully without needing to take drastic measures like weight sorting every single projectile every time I sit down at the reloading bench to put together .223 cartridges.

    But the proof for me will be in the pudding. There's some testing ahead for me, and getting my own results on paper is the only way I can confirm or deny anybody's educated guesses about what's going to happen when I pull the trigger. Looking forward to seeing what I can get with improved quality rounds on my next test day at the range. If it's just not getting there for me, that's when I know it's time to look into different powders, perhaps a different mold, etc.
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  13. #53
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    Quote Originally Posted by Larry Gibson View Post
    You will not be able to shorten the OAL enough to make any difference... ...given the nature of H335, the case capacity of the 223/5.56 case and the minimal amount you can seat the bullet deeper a sufficient increase in pressure just isn't going to happen.
    This is unsurprising, thanks for your input. I'll leave the COAL as is (just shy of max) unless I discover a compelling reason to change it.
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

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    You got it right BHjiu in that the rpm to ruin accuracy is so high that not only do we need not to worry about it, it doesn't make enough difference to care about.

    I'll lean towards a engineer schooled in the things that are needed to fully understand ballistics and such things as rpm effects like Brian Litz. He's not the only one schooled in it by a long shot.

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    BHuig you asked about a PID. HATCH, the moderator here, is the man to go to. He builds and sell him. Ask him your questions. I believe JonB in Glencoe is another to ask questions too, he's also a moderator.

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    I have added a video to the Test #3 post going over some of the new information I have picked up in the last week, and outlining the direction I'm headed in my testing.
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  17. #57
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    This has probably been stated here elsewhere, but I will revisit it to give it emphasis.

    There is an “easy” button and it is most beneficial to hit it first. Select a powder of such speed that it enables cycling of the action and no more. The AR will cycle and lock the bolt back at surprisingly mild velocity levels. Pick a bullet of good design and fit to your possibly generous chamber and throat. Use Dacron as suggested to avoid velocity swings from shifting powder position which produces inconsistent pressures and action cycling especially when flirting with the bottom end of reliable function.

    Such loads, for me, produce a useful point of impact at 100 yards when my rifles/carbines are zeroed at 200 yards with full power jacketed ammo.

    Once this is settled on, practice your brains out, shoot lots of groups, have fun as you have done something useful, made a decent load of considerable utility, and find out what the potential of “easy” is.

    If that becomes boring, you may increase the throttle and along with it likely also your frustration level. If you receive claims that great groups are no problem to achieve with cast at near or equal to full power jacketed bullet velocities, it is reasonable to ask to see multiple groups shot on the same piece of paper from said claimant so you may see that such results are produced by actual intent and not by accident.

    Proof of this type avoids cherry picking a group here and there and claiming it is average accuracy. Average accuracy is just that, and can be produced repeatedly and verifiably on demand. Do not take such things on faith. In that regard, pretend you are from Missouri.

    Have fun, but be realistic as well.
    Last edited by 35remington; 02-27-2018 at 10:57 PM.

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    Quote Originally Posted by 35remington View Post
    This has probably been stated here elsewhere, but I will revisit it to give it emphasis.

    There is an “easy” button and it is most beneficial to hit it first. Select a powder of such speed that it enables cycling of the action and no more. The AR will cycle and lock the bolt back at surprisingly mild velocity levels. Pick a bullet of good design and fit to your possibly generous chamber and throat. Use Dacron as suggested to avoid velocity swings from shifting powder position which produces inconsistent pressures and action cycling especially when flirting with the bottom end of reliable function.

    Such loads, for me, produce a useful point of impact at 100 yards when my rifles/carbines are zeroed at 200 yards with full power jacketed ammo.

    Once this is settled on, practice your brains out, shoot lots of groups, have fun as you have done something useful, made a decent load of considerable utility, and find out what the potential of “easy” is.

    If that becomes boring, you may increase the throttle and along with it likely also your frustration level. If you receive claims that great groups are no problem to achieve with cast at near or equal to full power jacketed bullet velocities, it is reasonable to ask to see multiple groups shot on the same piece of paper from said claimant so you may see that such results are produced by actual intent and not by accident.

    Proof of this type avoids cherry picking a group here and there and claiming it is average accuracy. Average accuracy is just that, and can be produced repeatedly and verifiably on demand. Do not take such things on faith. In that regard, pretend you are from Missouri.

    Have fun, but be realistic as well.
    Good advice and perspective.

    While I am not expecting shooting cast .223 at jacketed velocities with good groupings to be "no problem," I am encouraged that it may be possible. Won't know until I try. For the time being, I'm still looking for 2 MOA at 100 yards. If and when I decide to try and develop a more accurate load that I can shoot faster and out to longer ranges with better groupings, it will almost definitely be with a heavier bullet, and one with a better ballistic coefficient than the Lee 55 grain.

    At that point I fully expect my bullet quality will need to skyrocket - that's when weight sorting, using a PID in my melt while casting, and looking into conventional lube and heat treating for maximum alloy hardness comes into play, as well as more advanced case prep - in other words, that's when my amount of effort expended per round goes way up
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  19. #59
    Boolit Buddy
    Join Date
    Sep 2017
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    Utah
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    Update from today - I got to the range and shot my next set of ladders for Test #3.

    Results weren't as accurate as I was hoping, but I think I have probably discovered at least one or two major reasons why. Details in the post from page 2 of this thread labeled as Test #3, including the results video.
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

  20. #60
    Boolit Buddy
    Join Date
    Sep 2017
    Location
    Utah
    Posts
    177
    I picked up an inexpensive scope, and I'm itching to try it out. So even though I haven't had a chance to cast up some hard, heat-treated/quenched bullets to try with traditional lube, I will be hitting the range this coming weekend to see if I can get a better idea what these soft powder coated bullets are actually capable of. I highly suspect my own poor accuracy with iron sights was a significant limiting factor in my tests so far.
    Currently in the process of developing the "perfect" cast .223 load for my AR-15. Click here to follow my progress

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Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check