Nor should you be surprised we have to hear the RPM Threshold nonsense yet again.
Claiming shrinkage when the rest of us that have actually tried it KNOW it grows makes it seem as though he hasn't really tried it.
Pretty good example of why I don't spend much time here anymore. It's a shame, used to be a good forum.
Sent from my SM-G930P using Tapatalk
In the time of darkest defeat,our victory may be nearest. Wm. McKinley.
I was young and stupid then I'm older now. Me 1992 .
Richard Lee Hart 6/29/39-7/25/18
Without trial we cannot learn and grow . It is through our stuggles that we become stronger .
Brother I'm going to be Pythagerus , DiVinci , and Atlas all rolled into one soon .
I use copper babbit added to wheel weights as per the recipe given to me. A 230g Thor fell from the mold at .360 and after sitting for several months measure .361 on all I checked.
Same mold with straight ww's gave me .359
Any Cu enriched alloy I've used has added at least a thousandth or two to the diameter.
When dealing with islam one should always ask themselves: "What would Leonidas do?"
I DO love copper as a grain refiner,it seems almost magic that it (the boolit) can be as hard as it is, yet still deform/expand at somewere between 1500-1700 ( I don't have a chronograph). I have needed one for a while, but its not at the top of my priorities, need to check garage sales. I never see them in th S&S forum
An armed man in a citizen.
An unarmed man is a subject.
A disarmed man is a slave.
When dealing with islam one should always ask themselves: "What would Leonidas do?"
huh, I didn't know about having to shade chronographs, but I have heard of people shooting theirs. that's the kind of thing that is hilarious..... until it happens to you.lol thanks for the tip, are they expensive?
An armed man in a citizen.
An unarmed man is a subject.
A disarmed man is a slave.
http://www.magnetospeed.com/products/chronographs/
This is the one I have.
https://ads.midwayusa.com/product/62...ic-chronograph
THey have a cheaper model. I don't think it comes with as many spacers and the computer looks different but would be just fine if you can't justify the cost of the V3
https://ads.midwayusa.com/product/89...er-chronograph
When dealing with islam one should always ask themselves: "What would Leonidas do?"
those are cool! maybe I can find one used on ebay sometime. thank you for the info
An armed man in a citizen.
An unarmed man is a subject.
A disarmed man is a slave.
To All,
I strongly suspect that ANY of the .30 caliber or larger caliber rifle rounds (that are large enough to contain that much powder) are perfectly suitable to take most any American/Canadian game animal with a 180 or heavier grain GCCB bullet at 2,000FPS. = MANY a large bear in AK, elk, moose & even BIGGER/FIERCER GAME like TIGERS & GAUR have been successfully taken with a S-A War vintage US Krag government load of a 200 or 220 grain FMJ bullet of "cupro-nickel" at 2000 FPS.
just my OPINION, satx
possible and suitabl are two totally different things though, a circus elephant was once killed with a 22. hard to believe but it happened
An armed man in a citizen.
An unarmed man is a subject.
A disarmed man is a slave.
i am late on this thread, but....
i use certified copper babbit with other metal added for a full magnum load in my 350 remington magnum....
the goal was the lightest, toughest cast boolit possible. lots of tin and very little lead. i waited months to size them.
i am currently considering a 358 STW barrel. that same LONG 280 grain mould will come in handy with babbitt boolits. i think they are 1.208" long, .439 B.C.
they shoot great at 2400 fps with that little cartridge. the average weight was 247 grains from a 280 grain mould.
If one uses a high tin babbitt (popularly called Genuine Nickle Babbitt, which does not contain nickle but is fairly close to the same color as nickle) and an alloy calculator, he can add the babbitt to a lead/COWW alloy and get heavier bullets that will react well to high pressure/velocity while remaining malleable. One's goal should be a balanced alloy with about 2 3/4% antimony. By balanced I mean, the percentage of antimony equals ( or nearly so) the sum of the copper and tin. That relationship in the alloy has been working for me for several years. The bullets will stabilize in size and hardness in about 2 weeks. If they don't, the alloy has too much imbalance and is likely high in tin. My experience...hope it helps those that want to try it for their selves.
Edd
Charter member Michigan liars club!
"The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in Government." -- Thomas Jefferson
"Consider the clown(s) just one of God's little nettles in the woods, don't let it detract from the beauty. Sooner or latter you are going to run into the nettles regardless of how careful you are."
Beware of man who types much, but says nothing.
The shrinkage mentioned in my earlier post was addressing what occurs in the mould as the alloy solidifies before it is dropped from the mould. It is not in reference to what occurs at a later time as the solidified bullet ages (10 days to two weeks as mentioned). Even if the bullet size stabilizes that does not negate any imbalances in the bullet.
Also, in the example of the older 311455 mould I was referring to the use with the quarternary alloy Ideal #1. That has considerably more Cu in it (10%) than the alloy badgeredd recommends. I use the babbitt badgeredd sent me some years ago and have found his recommended percentages to make a good, malleable alloy as he states. It is unfortunate some let their personal dislikes cause them to misconstrue what is said. The fact they are getting good accuracy above the RPM Threshold as discussed by me is because I was discussing it in relation to the use of a ternary alloy such as COWWs and #2 alloy. The use of a quarternary alloy with copper in it as mentioned in this thread does raise the RPM threshold level above that for a ternary alloy. Still there is an RPM Threshold (albeit a higher one) with the quaternary alloyed cast bullets also. That is still the reason accuracy does not hold as high as with jacketed bullets. The velocity level where accuracy is lost is also the RPM Threshold.
I have proven the RPM Threshold by pushing a ternary cast bullet to 2900 - 3000 fps and maintaining 1 to 1.35 moa out to 600 yards.
If the mentioned 2400 fps with 350 Remington magnum was with a factory barrel then it was probably a 16" twist if in a Remington. If so that is only 108,000 RPM.....well below the RPM Threshold for a ternary alloyed bullet. It should have proved accurate. FYI; in a 14" twist it is still below the RPM Threshold and in a 12" twist it would be at the top end of the RPM Threshold.
Last edited by Larry Gibson; 05-04-2018 at 12:00 PM.
Larry Gibson
“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla
Larry you've proven nothing concerning your threshold with the 30 XCB at 2900-3000 fps providing that the rifle you shot it in I believe has a 16 twist so that makes the rpm 135,000 which isn't no ways out of your theory range. Make note too that you used a "fitted" bullet which brings up to your theory test done with non fitted bullets of mediocre design and of bad casting which you yourself have admitted in not only a recent thread in the Cast Boolit section in which I told you that you can't do an accuracy test of different twists with cast bullets because they aren't nearly perfect enough no matter how well they are cast. Your rpm and twists tests are flawed. Couple that up with Bryan Litz saying you can't use three different rifles no matter how close they are to one another. You read it.
I'm not arguing with nor trying to run you down. Too many people here have pushed well beyond your threshold with accuracy which you keep moving up. A threshold is the magnitude or intensity that must be exceeded for a certain reaction, phenomenon, result, or condition to occur or be manifested. In your case that certain reaction is very bad accuracy or bullets flying wild. Your threshold is a set thing, one can't keep pushing it up. I surmise that you wish you never came up with that theory because it's coming back to bite you in the back end.
Are you positive that the ternary alloy you speak of so often is indeed only lead, tin, antimony and does not have any other elements in it such as zinc, arsenic, aluminum, copper, to just name a few? If you are how so?
"I'm not arguing with nor trying to run you down."
Who are you trying to kid.......
"Too many people here have pushed well beyond your threshold with accuracy which you keep moving up."
No they have not. They have pushed it up just as I said years ago and have repeatedly demonstrated it could be done. "A threshold is the magnitude or intensity that must be exceeded for a certain reaction, phenomenon, result, or condition to occur or be manifested." That is absolutely correct; exceed that condition and inaccuracy results, especially in a non-linear fashion as the range increases. However, your once again incorrect assumptions of what I mean are, in fact, incorrect. The inaccuracy does not have to be "very bad accuracy or bullets flying wild." It can simply be those uncalled flyers a bit out of the group. Also a sure indication is simply non-linear group expansion as the range increases. The RPM Threshold is not biting me at all but it sure does irritate you and some others. I never said the RPM Threshold was "a set thing". YOU, as you or as your "cuz", have continually said it was a "limit" even though I have said from the very beginning it was not a "limit" but that it could, in fact be pushed up or down.
Your inane accusations of me using poorly cast bullets that were not "fitted" is also a blatant lie. You really need to quit using that because everyone sees it for what it is. I never ran a test with "non-fitted" bullets. All were sized/fitted to fit the throats. The 311291 I used in the initial test was also used by myself and another member in 10" twist 30-06s demonstrating pushing the RPM Threshold up with 1 1/2 moa accuracy into the 2100 - 2200 fps range. I also have used the 311466 and 30 XCB bullet in 10" twist .308Ws and 30-06s with SAAMI or M118/M72 match chambers to 2350 2400 fps with the same 1 1/2 moa accuracy and done it with 10 shot groups. recently I demonstrated to waco such accuracy at 2365 fps out at 500 yards from a 10" twist .308W with a M118 chamber. Nothing was "fitted" beyond sizing the bullet to the chamber throat.
If there is not an RPM threshold then how is it most cast bullet loads with fast and medium burning powders lose accuracy when they exceed 140,000 RPM......How come you nor no one else shoots cast bullets of binary (lead and tin), ternary Lead, antimony, tin) or quarternary (lead, antimony, tin, copper) alloys out of a 10" twist .308W or 30-06 at jacketed velocities with equal accuracy? If there is no RPM Threshold how come accuracy does sometimes go very, very bad very, very quickly above a certain RPM? Yes, the RPM Threshold is well proven regardless of what you "surmise".....
Larry Gibson
“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla
I think you fellows need to realize I am reading this thread and I feel all of you are entitled to express your theory but the running another person's theory down will stop now. Go prove your theory post your finding and leave the nitpicking one another out of cast boolits.
Thank you,
Last edited by Larry Gibson; 05-04-2018 at 11:59 AM.
Larry Gibson
“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla
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 |