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5,000 fps! well, not yetDiscussion regarding the reloading of ammunition and tuning of loads for accuracy
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Handloader Super Member
Joined: Aug 22, 2005 Posts: 1032 Location: Phoenix, Arizona
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Posted: Thu Aug 17, 2006 7:53 am Post subject: Re: 5,000 fps! well, not yet |
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george20042007 wrote: |
Handloader, in your quest for 5000 fps, I'd be interested in knowing the shooting details, i.e. are you allowing the barrel to cool between shots, barrel prep., how often do you clean the barrel, etc.
Other threads have addressed such issues, but, I'd like to know more about your shooting considerations as opposed to bullet type, powder, primer, and brass used.
Keep it coming... |
Howdy George
At this point no extraordinary proceedures have been incorporated, although, some may be needed to reach goal. One impediment is the 1 -12 twist. If it were a 1 in 14, velocities would be higher with each of the loads tested thus far.
The barrel is given two minutes between shots. No cleaning is done except as needed or if their is a change in components*. As much as possible, I try to time my sessions with temperatures in the 68 to 75 degree range which means trips to Prescott this time of year. I fire lapped the barrel on the first session and, then, treated it with Microlon, a standard proceedure I use with all new rifles.
* Most factory barrels are fairly rough when new and some may have tight spots along the bore. Looking at a new barrel through a 25X borescope is almost frightening! I use the NECO fire lap process which removes the feathered edges on button rifled bores and polishes, or laps, the barrel to where it is significantly smoother and more uniform. After this process, cleaning is done only as a factor of deteriorated accuracy. I have several Swifts and on one of them I can go just over 100 rounds before cleaning is needed. Most other fire lapped centerfires will go 40 to 70 rounds before any deterioration of accuracy is noted. Because fire lapping makes the bore smoother, cleaning is easier, too. On high quality cut rifled barrels (for example, Krieger) no fire lapping is needed as the barrels have been carefully lapped before shipment. On hammer forged barrels, rifling is often smoother than button rifled barrels in my experience. Finely lapped barrels will yield lower SDs, increase accuracy and will clean up much faster.
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Jack Member
Joined: Oct 19, 2005 Posts: 98
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Posted: Thu Aug 17, 2006 9:16 am Post subject: Re: 5,000 fps! well, not yet |
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Might be worth noting that the M1A Abrams uses a smoothbore cannon- the stabilizing spin is imparted by fins on the projectile, not rifling.
Far less bore friction than a rifled barrel, FWIW.
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Al_Sohlstrom Member
Joined: Aug 30, 2005 Posts: 75
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Posted: Fri Aug 18, 2006 1:27 am Post subject: Re: 5,000 fps! well, not yet |
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Hi
Jack wrote: |
Might be worth noting that the M1A Abrams uses a smoothbore cannon- the stabilizing spin is imparted by fins on the projectile, not rifling.
Far less bore friction than a rifled barrel, FWIW. |
The main advantage of the smooth bore gun is that you don't have to precompensate for stabilizing spin when you manufacture a High Explosive Anti Tank (HEAT) round.
The stabilizing spin of a rifled-barrel fired round screws up the formation of the high pressure jet in the HEAT round, decreasing the thickness of the armor it will defeat. The only way to UNscrew-it-up is to machine an Unscrewing-it-up counter-rifling in the metal cone that forms the jet. The counter-rifling of that cone is mathmatics, physics, terminal ballistics and engineering gone MAD! Take out the rifling, though, and you're back to plain, un-counter-rifled cones and un-screwed-up high pressure jets.
For what it's worth: You can fire MISSLES out of a smooth bore gun, as well. Not that I'm saying that I think that they ARE, or that they WILL, or even that they MIGHT; Just that they CAN.
_________________ "Al's Postings," from the, "Good Eats Fan Page."
At the heart of evey complex problem lies a graceful solution involving explosives. |
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Vince Site Admin
Joined: May 25, 2005 Posts: 15704 Location: Brisbane AUSTRALIA
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Posted: Fri Aug 18, 2006 6:03 am Post subject: Re: 5,000 fps! well, not yet |
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Al_Sohlstrom wrote: |
For what it's worth: You can fire MISSLES out of a smooth bore gun, as well. Not that I'm saying that I think that they ARE, or that they WILL, or even that they MIGHT; Just that they CAN. |
They have been firing Rocket Assist Projectiles from artillery pieces for some years...I suppose they could be classified as a missile of sorts.
Cheers, Vince
_________________ Cheers, Vince
Illegitimi non carborundum
(Never let the bastards grind you down)
Live simply. Love generously. Care deeply. Speak kindly. Leave the rest to God.
"Nulla Si Fa Senza Volonta."
(Without Commitment, Nothing Gets Done) |
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Al_Sohlstrom Member
Joined: Aug 30, 2005 Posts: 75
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Posted: Fri Aug 18, 2006 9:49 am Post subject: Re: 5,000 fps! well, not yet |
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Hi
Vince wrote: |
Al_Sohlstrom wrote: |
For what it's worth: You can fire MISSLES out of a smooth bore gun, as well. Not that I'm saying that I think that they ARE, or that they WILL, or even that they MIGHT; Just that they CAN. |
They have been firing Rocket Assist Projectiles from artillery pieces for some years...I suppose they could be classified as a missile of sorts.
Cheers, Vince |
Naw - RAP's a whole 'nother thing. It's just an effective way to get more propellant behind the projectile, and thus greater range, and not over-pressure the barrel and breech of the howitzer. Somone, somewhere, saw the RPG-7's setup - with the expulsion charge and the sustaining motor - and thought, "you know - if that were just 155 millimeter or so...".
The Shillelagh was a real wire-guided missle, and, at the time, had the highest homogenous-steel penetration of any American shaped-charge munition. The TOW missile beats it (at a vaguely-remember around-13- feet of homogenous steel), hands down, now, and I believe that the later model Dragons matched it while being smaller and lighter.
I just find if very interesting that ALL the new fire-and-forget anti-tank stuff clocks in at right about 5 inches in diameter, and the M1A has a right-about-5-inch-diameter smooth bore gun....
_________________ "Al's Postings," from the, "Good Eats Fan Page."
At the heart of evey complex problem lies a graceful solution involving explosives. |
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Crackshot Super Member
Joined: Oct 23, 2005 Posts: 1693 Location: Mich
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Posted: Fri Aug 18, 2006 10:32 am Post subject: Re: 5,000 fps! well, not yet |
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Hello guys! Again I will bring to your attention that "yes" there is a gun fired round that exceedes 5000 fps. the only one that matches it is our Abrahms tank gun, but not by much.
It is the MECAR 105mm TPDS-T Practice shot M724 made in Belgium. Otherwise known as a submunition, It is a Target Practice Discarding Sabot-Tracer. Made for the British 105mm Tank guns made in the Mecar plant in Belgium.
Complete round weight is 29.5LBS
Projectile weight is 6.8LBS
Muzzel velocity "IS" 5,035 FPS
It's range is in excess of 7,650 yds.
It is not a rocket assisted projectile.
_________________ The human mind is the weapon, the gun is just one of its tools. |
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DallanC Site Admin
Joined: Jan 18, 2005 Posts: 3571 Location: Utah
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Posted: Fri Aug 18, 2006 12:43 pm Post subject: Re: 5,000 fps! well, not yet |
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Crackshot wrote: |
It's range is in excess of 7,650 yds.
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AND BEFORE SOMEONE ASKS, NO I WILL NOT ADD IN THE EFFECT OF THE EARTHS ROTATION ON PROJECTILS FIRED AT THAT RANGE INTO THE NEXT VERSION OF POINTBLANK!!!
-DallanC
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Crackshot Super Member
Joined: Oct 23, 2005 Posts: 1693 Location: Mich
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Posted: Fri Aug 18, 2006 1:19 pm Post subject: Re: 5,000 fps! well, not yet |
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AWWWWWW..... Why not? :):):)
_________________ The human mind is the weapon, the gun is just one of its tools. |
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Dimitri Super Member
Joined: Nov 25, 2005 Posts: 5944
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Posted: Fri Aug 18, 2006 1:33 pm Post subject: Re: 5,000 fps! well, not yet |
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Programming for the Earths spin must be a nightmare.
You'd need to:
Know your Latitude to get the EXACT diameter of the earth where you are, the angel diffence between true north or south and where your aiming, then you need to calculate the diameter of the earth divided by the time it will take the projectile to reach the target then you'd calculate how much is the "corrected" amount based on the angel your shooting.
Dimitri
_________________ A thousand hills, but no birds in flight, ten thousand paths, with no people's tracks. A lonely boat, a straw-hatted old man, fishing alone in the cold river snow. |
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george20042007 Super Member
Joined: Jan 27, 2006 Posts: 568 Location: Arizona
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Spacedone Member
Joined: Nov 04, 2005 Posts: 266 Location: missouri
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Posted: Fri Aug 18, 2006 5:56 pm Post subject: Re: 5,000 fps! well, not yet |
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a trick navy question
what is the velocity of a 12 inch gun at the target.
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Crackshot Super Member
Joined: Oct 23, 2005 Posts: 1693 Location: Mich
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Posted: Fri Aug 18, 2006 6:30 pm Post subject: Re: 5,000 fps! well, not yet |
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As fast as It needs to go to get the job done.:)
I have some info here on the 16 inch naval gun, but none on the 12 inch naval gun. sorry.
_________________ The human mind is the weapon, the gun is just one of its tools. |
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Dimitri Super Member
Joined: Nov 25, 2005 Posts: 5944
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Posted: Fri Aug 18, 2006 8:03 pm Post subject: Re: 5,000 fps! well, not yet |
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Arnt the original battle ship guns accurate to under 1 MOA ?? I thought I read that somewhere
As for them firing, I wouldnt want to be anywhere within 20 milies (their max range) from it
But seriously though Bushmaster would have this answered properly
Dimitri
_________________ A thousand hills, but no birds in flight, ten thousand paths, with no people's tracks. A lonely boat, a straw-hatted old man, fishing alone in the cold river snow. |
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Crackshot Super Member
Joined: Oct 23, 2005 Posts: 1693 Location: Mich
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Dimitri Super Member
Joined: Nov 25, 2005 Posts: 5944
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Posted: Fri Aug 18, 2006 8:23 pm Post subject: Re: 5,000 fps! well, not yet |
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Crackshot,
I didnt know that they were accurate to 26 miles thanks for the correction. Still pretty far. That would really require doing math for the Earths spin.
Also if I did the math right I guess they arnt Sub-MOA accurate. At 26 miles 1MOA is 13.3 yards. That means the battleships guns at that extreme range are accurate to 7.5MOA
Dimitri
_________________ A thousand hills, but no birds in flight, ten thousand paths, with no people's tracks. A lonely boat, a straw-hatted old man, fishing alone in the cold river snow. |
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