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One of Us |
Base distortion is another matter that destroy accuracy and unless one can capture fired bullets one might never know it's occuring.  I'm not sure how RPM would affect such a bullet. Muzzle blast should have a pronounced effect. Regards 303Guy | |||
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| One of Us |
That's not what nose slump is. I believe "slump" is incorrectly used. What you are seeing is "tilt". The bullet is tilted in the bore. That will make the nose look like it slumped. | |||
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| One of Us |
That last example was to illustrate the base distortion. That bullet could well have tilted, hence the uneven base. I don't think there is visible nose slump there but the fact that the nose got bent on impact could indicate bullet yaw so I would agree with you in this instance. However, the nose bending could be caused by the nature of the catch medium - bundled rags. I have since made a mold that produces a bullet that sits firmly in the tapered throat and does not tilt. But where I'm saying there was nose slump or bump up, there can be no doubt it is nose slump. You see, I measured the nose diameter before and after firing and also the ogive and behind was bore diameter with the patch. After firing the nose section in front of the patch was expanded to fill the grooves on the full circumference. Regards 303Guy | |||
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| One of Us |
So you are saying that you can recover fired cast bullets 100 percent undamaged? Is that what I am reading? Pretty hard thing to do. | |||
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| One of Us |
No, unfortunately. I can fire them slower and recover them relatively undamaged. Or I can fire then at speed and recover only the undamaged base. This bullet showing nose slump is also showing impact expansion. However, the portion just in front of the patch impression is showing rifling and groove contact. Now the impact damage has also expanded the patch impression portion to above bore diameter. So examining captured bullets is quit tricky. But I say again, I have the samples in my hand which I can examine in a way I cannot capture in a photo so it becomes difficult for you to actually see what I'm seeing.  This one shows base damage for example. This one shows a good base.  Noses are difficult to examine but possible at lower speed with appropriate catch medium.   This one shows base edge feathering which can't be good for accuracy. The bullet does appear to have entered the bore concentrically.   This one shows base cupping but no base edge feathing and it was an accurate bullet in the field with a group size of 1½ MOA wit open sights at 100m. Regards 303Guy | |||
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| One of Us |
That's why gear and I are working on a method to recover them undamaged. I thought what would be nice is if there was a huge flat area that had a just as huge shallow puddle of water on it say 12 inches deep and you stand in the center of it with a few spotter friends and fire your rifle as straight up as possible. The NRA did something like this where they erected a pine shooting platform off the coast of Florida where the water level is very shallow for a long ways. I forget the details but remember some the calibers they tested were the 8mm Mauser and the 303. The most amazing thing to me about it was the time period it took for the bullets to return to Earth. Amazingly long time I thought. I believe the test was to see how much energy the bullet had just free falling back to Earth. They plumed the rifle actions as straight up as possible and only a few bullets, if I remember correctly, fell on the platform. They said, again just from memory, that they either dented the wood or stuck in the a little. They said they didn't believe they would be lethal. So I would hope with my large shallow puddle ideal that there wouldn't be enough velocity in the free fall to do any damage at all upon hitting the water. Still even seeing where they splashed would be hard to recover I'll bet. Wear a hard hat if you do this lol. | |||
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| One of Us |
Firing straight up while standing in a shallow pond would be the easiest way to recover a bullet undamaged, but imagine how little wind it would take to blow it hundreds of feet away from where it was launched. This spring sometime I'm going to start in on the sawdust trap. Anybody remember how long Mann's trap was to catch those low-velocity breech-seated bullets? If it has to be more than 24 feet long it might be a logistical nightmare. But if we can recover bullets that shoot very accurately at one velocity and begin to scatter at a slightly higher velocity, preferably with the same powder just more of it, hopefully we can give a positive ID of what happened in the barrel to make the bullet inaccurate. Joe and I are betting that something is happening to the bearing surface to cause the problem, since some very careful study of paper jackets pretty much eliminates nose slump, internal voids, and base deformation as a cause. Gear | |||
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| One of Us |
Knock yourself out... but you might want to reference Major Julian S. Hatcher's Notebook, Third Edition, pgs. 510-519, appropriately titled "Bullets from the Sky". | |||
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| One of Us |
Yeah Hatcher talks about the off Florida coast shooting and some bullets came down over a 1/4 mile away and others they didn't have a clue to where they went. He said with a machine gun it was easy to see the splashes in the rather calm water and they could adjust the gun to move the bullet splashes where they wanted them. He said they concluded that the bullets were returning with about 300 fps velocity and thus figured the 06 bullet they used had an energy of 30 foot pounds. He went on to say that the Army test said that it took 60 foot pounds for a bullet to disable a man. So I surely wouldn't want one hitting me or landing on my head. He said the 06 bullet dented the pine platform about 1/16th inch. So a hard hat would protect your head. Still a difficult feat to do unless you live in Florida. | |||
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| One of Us |
I am familiar with Hatcher's tests. That's why I'm going to use the same approach Mann did. The only issue is I'll have to establish the accurate/inaccurate loads on a different range, testing at 100 and 200 yards to check for non-linear dispersion, then shoot into the trap at basically 20 yards or so. Terrain at my property doesn't permit long-range shooting, and I can't build the box at my local public range. I also have a quantity of crumb rubber, it would take a lot less of that to stop a bullet, but I think it tears up the bullet more. Perhaps a combination of the two, with crumb rubber being the second stage of the trap, would work. Gear | |||
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| One of Us |
I think if you developed a vertical rest for a rifle you could fire it straight up and adjust fire until the bullets landed close by. I did this with a .22 LR and no rest 50 years ago and got them to land in a stock tank every now and then. | |||
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| One of Us |
Hatcher done that exact thing. | |||
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| One of Us |
Here's another classic example of really high rpm and the ugly double helical spiral causing the bullet nose to not fly in the proper position and destroying the accuracy. NOT!!! Look at those first two reloads the lighter/shorter bullet was the most accurate and had the highest rpm. By the way the rpm of those first two loads are 327360 and 319360. Because the bullet was oscillating so bad from the double helical spiral, high rpm, and nose not in the correct position one could hear the high pitch buzzing of the bullet flying through the air from all the shooting positions at the range.  | |||
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| One of Us |
Yes except they are tiny jacketed bullets. 1. The jacket is relatively strong compared to the radius of revolution. 2. And the radius of revolution is tiny. Centrifugal force is proportional to the square of the radius. 3. The bullets are not very long so they are much stiffer than a long relatively soft cast bullet.
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| One of Us |
Exactly and my point being is that the spin is a lot more then needed according to the "experts" on the "other" forum. Can't get accuracy at high rpm no matter what the parameters are....in comparison to the same load and rifle except with a slower twist. | |||
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| One of Us |
Well here we go again, the Golden Boy over on castknowit.com forum posting the proven Einstein and Werner Von Braun cast bullet RPM Threshold: My 308 CBC is my own design I came up with back in the ‘70s. I use US M80 cases (7.62 NATO) to have thicker brass in the neck area for neck turning. It also uses 7.62 NATO brass because I had so many. I can use .308W cases but the necks will be thinner and case capacity larger. The idea back then, developed over several years, was that the most accurate cast bullet cartridge would give 100% load density with a medium burning powder. The 30-30 was very efficient at 100% load density with 170 – 180 gr cast at 2200 +/- fps out of a M94 rifle with 24” barrel. I wanted to basically duplicate the 30-40 milsurp velocity with 210 – 220 gr cast bullets in a rimless case (for feeding through a bolt action Mauser) that had 100% load density with 4895 also (because I had a lot of it) at 2200 fps. I also wanted the case to have the longer neck of the 30-30 and ’06 to keep the GC and lube grooves in the case neck. Back then all the published experts said the 311284 was just the ticket and a 2 groove 'A3 barrel was just the cat's meow for that cast bullet. I had a new (still in wrapper & cosmoline) and a SR Mauser action for the project so I was heavily watching and reading all about the “inherent accuracy” of the short squat cartridges. Using a Powley Computer to determine how much case capacity in water a case would need to have to drive a 220 gr bullet at 2200 fps with 4895 I shortened a .308W FL die and began to set the shoulder back Of WCC 7.62 cases until that much water came just to the junction of the case neck and case shoulder. The case neck was then trimmed back to max ’06 length. Turned out the case oal was exactly 2.00”. Seemed like a good plan at the time and I had the chamber cut off the barrel had it installed on the Mauser action. I explained earlier the chambering method. When it was done I thought I had the “perfect” cast bullet rifle/cartridge. In working up loads I found several things wrong; 1st case capacity was still too large for 4895 as I hit 2200 fps (yes I had an Oehler chronograph back then) at about 80% load density. Seems none of the literary “experts” I read mentioned that cast bullets will give a higher velocity than an equal weight jacketed bullet with a given powder charge of the same powder. Thus I switched to H4831 and and a couple other slow burners and hit 2200 fps at 100% load density. Sounds good right? Well it wasn’t…….accuracy sucked above 1900 – 2000 fps regardless of the powder used. 2nd problem was the scraper groove in a 311284 is a weak point. When accelerated hard the long heavy nose sets back unevenly, even in the broad lands of the 2 groove barrel. I tried different alloys and even went to heat treating and WQing yet accuracy still went south above 1900 – 2000 fps. I switched to 311299 which doesn’t have the scraper groove and managed to hold accuracy (sub 2 moa with 10 shot groups) up to 2050 – 2100 fps. Above that accuracy suffered very quickly. I was at a loss for numerous years with the 308 CBC rifle languishing in the back of the gun cabinet with little use as it was really no better than any standard ’06. I could get 2200 fps with 2 moa accuracy out of the M94 30-30 with 311291s and 311041s and the same 2 moa accuracy at 2200 fps with the 311299 out of a M70 .308W. . I just couldn’t understand why the 308 CBC wouldn’t do the same. When I queried the “experts” they all said it was balancing the bullet hardness to the psi, the bullet alloy, lube, sizing, powder….yadda, yadda, what we still hear about these days…….. As the years went by and I shot more and more with the .308 CBC trying all the suggestions to not avail I was at a loss. Then I read a question and answer in the American Rifleman that led me to the answer…..Question; why can I get excellent accuracy with a 311359 at 40, 000 psi from my M1 Carbine but when I load the same bullet in my ’06 to the same 40,000 psi the accuracy is nonexistent? Answer; because at 40,000 psi in the ’06 the velocity is a lot higher. I wasn’t sure of the velocity of that ’06 load but that answer tied in with another observation made by another gun writer about the adverse effect of too much RPM on unbalanced bullets. That got me to thinking. What was the difference between the M1 Carbine (I had a couple) and shot the same 311359 and knew I could shoot it at 1900 fps with excellent velocity? I also knew that same 311359 shot very accurately in my own ’06 up to 1900 fps and in the M70 .308W up to 2200 fps before accuracy went south. It did not appear the .308W and ’06 loads had anywhere near the psi as the .30 Carbine load. Yet the M94 and the M70 would shoot the same bullets 200+ fps faster so what was the difference? I computed the RPM in the 10” twist ’06 and the 10” twist 308 CBC with a velocity of 1900 fps and the RPM of the M94 and the M70 at 2200 fps and you know what? They were very close to the same RPM!!! That got me to testing numerous other cartridges with different twists and that’s how I developed the RPM threshold. Not going to go into that but suffice to say it is real. So with the 308 CBC chambered in that 2 groove ‘A3 barrel with 10” twist it is no better than the standard ’06 or .308W in 10” twist barrels. Knowing what I know now about RPM and cast bullets if I had chambered it in a 12” twist barrel. That’s the twist the M94 and M70 had and is the reason they shot well at 2200 fps and the 10” twist barreled 308 CBC shot well up to 1900 – 2000 fps. If I could do it again knowing what I know now the 308 CBC would have a 12” twist and it would shoot the 311299 with good accuracy upwards of the original goal of 2200 fps…….we live an learn……… Yeah live and learn....by looking at this:  That's five shots 1/2 inch group at 100 yards with a 10 twist AR10 in 7.62 NATO with a 180 grain cast bullet at a higher velocity then the garbage mentioned in the beginning of this post. One has to know his limitations shooting cast bullets especially at HV in fast twist, thus the reason they have to have slow twist barrels to get any kind of accuracy from their cast bullet loading limitations. Too bad the dummies believe that idiot and never accomplish what all can be done with cast bullets. | |||
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| one of us |
I like to see a tape measure or a dial calibers put next to the above group. What is the Velocity. Just want the facts. | |||
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| One of Us |
You'll just have to take my word for it. Velocity is right at 2400 fps. | |||
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| one of us |
I guess I find it hard to believe that's a half inch group its at least 4 bullet holes high at .308 in dia. that's 1.232. Center to center 4 high gives you over .6 Even with the paper folded in less say they are .250 around that still an inch. Even if they were .224 4 high gives you over 3/4 of an inch. The 4 bottom ones could be a half inch but the from the top to the bottom opens it up. I guess its all in the way one measures it. | |||
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| One of Us |
Actually center of the top hole to center of the lower hole on right is .5 inch. What have been your experiences with a 308 cast bullet with 10 twist in any type of rifle at high velocity? I have Garand with a scout scope on it (my eyes just aren't good enough for iron sights anymore) that is chewing a hole for 8 shot (larger then the 308 target, about .75 to 1.0 inch with 212 grains cast bullet at little over 2200 fps. I have an adjustable gas cylinder plug on it so no I'm not over pressuring it and it's a slow burning powder load. | |||
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| one of us |
Nope I shoot all by cast at lower vel. They shoot good I am not saying that they can't be shot at higher vel. enough people do it. Its just that I don't care to take the time to do it. A good cast bullet well shoot and kill well doesn't need a lot of vel. to do so. For what I use them for pistol and rifles 800 to 1500 get it done for me. | |||
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| One of Us |
And I am not saying that one has to shoot his cast rifle bullets at the absolute top high velocity, but rather that it can and is done...with very good accuracy. There are instances where 1500 fps is not enough velocity to stabilize some cast bullets. Are you telling me for example that say a cast 30 caliber bullet of 165 grains in a 30-30 with the muzzle velocity of 1500 fps is going to get the job done for say whitetail deer hunting? You realize what the velocity of that bullet is at 100 yards? No sir Pdog I'm not buying that is good enough. It's underpowered and you know it. I guess if you personally are just shooting at paper, yes, then you are correct. You are, however, not correct for all the applications of shooting cast bullets. | |||
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| one of us |
Yes a 165gr bullet at 1500 well easily kill a deer at a hundred yards. Most likely well shoot right through one side to the other. I guess depends what you consider under powered personally I wouldn't have any trouble shooting and killing a deer with that load I killed plenty with less powerful loads from hand guns. Its all about placing the bullet in the proper spot. | |||
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| One of Us |
You know, you sing a different tune on Castboolits shooting paper patched cast bullets over 3000 fps from your 300 Rum...so whats this baloney about your 1500 fps limit. Only different is patched protects the bullet going down the bore, it's still the same alloy as cast. Hell you can if shoot patched pure lead at HV. What are you finding a need for HV with that??? Take the 311291. Lyman doesn't even list a 1500 fps muzzle velocity in their ballistic chart, but I can you that it's down in the 1200's at 100 yards. Yeah, you can kill a deer with a 22 rimfire too if you put the bullet in the right place. | |||
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| One of Us |
Funny: when I measure the distance between the holes using the computer screen, the distance is approximately 1.25" c to c. How much did you blow up the target so you could put it into your response? Something smells darned fishy... | |||
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| One of Us |
on my screen he's shooting a .89 caliber. with a 2.0 group. so dividing it down makes it @ .70 outside to outside. | |||
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| one of us |
It what I like so what, you like shooting them faster so what. Different people use different bullet types for many reasons. Heck I like to shoot cast down round 600fps to 700fps because out of a long barrel they are very quite. They kill well also out to 50 yards or so. My 460 gr .458 bullet penetrates like crazy at 700fps and sounds like about a 22rf from a rifle. Am I complaining about you shooting cast at any speed you want NO. I am just questioning that one group size just post it with a scale/ruler along side of it. Just pissing and moaning about speed does nothing to prove that's a .5 inch group. | |||
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| One of Us |
In a way you did complain about what speed I shoot at by remarking you don't shoot over 1500 fps and that's all you need with a hint that it's all anyone else needs too. There is no difference in what I'm doing and what you're doing except your technique is paper patching. Why don't you limit your pp to 1500 fps? Now if I had the target I'd put a ruler on it and scan it again, but unfortunately I pitched it. If I saved all the targets I shot I'd need a warehouse to house them. I don't want a collection of flammable paper around. I will search again and see if it's around somewhere. Are you going to be like the original butt holes and want to come to the my house with CBS, ABC, and NBC camera crews to see if I shot it??? Kind of like if I ask you if you're a good cop. You would say yes. Do I take your word for it or have NSA investigate you and give me a report. I knew you would get around to larger calibers. 1500 fps is pretty well moving for the old 45-70 and the big heavier bullets have lots of energy and penetration in them at very low velocities, but smaller calibers do not. My 6x45 is very capable of shooting small group and at long distances. I love varmint hunting and my cast bullet in that caliber will shoot much flatter if it starts out at a higher velocity and make the hunting of them much easier and enjoyable. So fine, you like slow speed (for naked cast bullets, but HV for pp) and I like HV for naked cast. The group is what I say it was. | |||
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| one of us |
Only in your mind did I complain. I just stated what I do. I never stated any thing about PP. you must be confusing me with some one else. I shot a lot of super quite loads using a 90gr .312 bullets out of 308 cal. rifles around 800fps. | |||
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| One of Us |
 Boy, you cast underachievers sure will go to great lengths to stop those who want to learn more about shooting cast bullets. Hey if you're needing money for your medical expenses why don't you sell your over 10K worth (your words not mine) bullet molds on Ebay and make even more then that? | |||
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| One of Us |
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| One of Us |
Hateful son of a dog... I will sell my 37 six, eight and ten cavity Hensley and Gibbs moulds when I damned well want to. It certainly won't be when you suggest it! And I will tell you this: the LAST thing I would do if I were trying to help others improve their cast bullet shooting skills would be to post a picture of a target with no measurement verification AND then claim I threw it away because I was afraid of a fire.  You have been called out on the veracity of your word before, on this forum and others, have been banned from one site, and yet you continue to claim super accomplishments with nothing to prove your claim. It is as Bartsche says: "Talk is cheap; it takes money to buy whiskey." "The older I get, the better I was." Sound familiar? | |||
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| One of Us |
 Feel better? Did I hit the right button? | |||
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| One of Us |
It's taken some of you gentlemen long enough to figure out that this doofus does all of his shooting sitting at the keyboard, and punches pencil holes in targets for groups. Cast bullet holes usually have the lube as a faint line around the hole. I think they let him stay here so the humor section doesn't get overrun... | |||
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| one of us |
recovering a bullet with very little damage here in the north woods is fairly simple in the winter time. About 80 percent of the time I recover bullets that could be taken and reload as is. 6 feet of snow bank works well I taken many a cast bullet lube them run them through the sizing die just because I can and reshoot them. | |||
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| One of Us |
I wish I could do that. Be a long wait for the snow to melt. | |||
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| one of us |
This year was very long we had 14 inches of snow the first week of May. | |||
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| One of Us |
I believe you, have a friend that lives in Madison. He told us you have to rake the snow off your roof so it doesn't cave it in if you're getting a lot of snow at the time. Wow! | |||
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One of Us |
We are about to get three days of snow but here that might only mean 4-5 inches and is is often gone within another few days so that wont work for us here either. | |||
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| One of Us |
Hey Garry, I guess those pine needles didn't work out? For a crazy thought I wonder how much solid styrofoam one would need to stop a bullet and if it would indeed not damage the bullet. | |||
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