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BlackpowderSweden
04-26-2013, 11:24 AM
I have been testing with the 6.5 Cruise Missile in my 6.5x55
So far have been quite succesful!

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC0021135.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC0021135.jpg.html)

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC00213.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC00213.jpg.html)
Nose Sized to bore dimension (6,49)

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC00214.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC00214.jpg.html)
Base Oversize to fit the case neck when chambered, with minimal blow by

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC00212.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC00212.jpg.html)
Catridge OAL

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC00216.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC00216.jpg.html)
Brinell Hardness

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC0021735.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC0021735.jpg.html)
Group 50m Benchrest

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC_1808-Kopia.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC_1808-Kopia.jpg.html)
100m Group

http://i68.photobucket.com/albums/i15/Nijoto/6-5x55/DSC00174-Kopia.jpg (http://s68.photobucket.com/user/Nijoto/media/6-5x55/DSC00174-Kopia.jpg.html)
Another 3-shot 50m group

Blintersifrid
04-26-2013, 01:47 PM
Wow.

That's quite the projectile there.
I see how it got its name.

How much does one of those weigh?

'Sifrid

Char-Gar
04-26-2013, 02:07 PM
How fast are they flying?

ukrifleman
04-26-2013, 02:40 PM
I use the Cruise Missile bullet in my 6.5x52, M91 Carcano with some success.
I trialled the original 170gn bullet, but found the best for my rifle was a cut down mould that produced 150gn bullets.
ukrifleman.

BlackpowderSweden
04-26-2013, 02:44 PM
The bullet weighs 170gn
I was using 16gn old Norma R123, similar burnrate to 2400?
Velocity was about 1650fps
Will try some Norma 200 and XMP5744

justing
04-26-2013, 02:46 PM
that's one big boolit.

BlackpowderSweden
04-26-2013, 03:47 PM
Ukrifleman, I have two moulds as well, have been thinking of milling down one of them like you have done.
Then I would probably not have to size down the nose to make it chamber.

hickfu
04-26-2013, 03:58 PM
Hey those look pretty cool, Maybe I should try something like that in My 6.5x57 Mannlicher....

Doc

ukrifleman
04-26-2013, 04:23 PM
The cut down mould works well for me. I use the bullet un-sized at .2695 in my Carcano, with the gas check attached with Loc-Tite and lubed with 2 coats of Lee Liquid Alox.
ukrifleman.

Larry Gibson
04-26-2013, 04:50 PM
From the bullet holes there appears to be some instability?

Larry Gibson

swheeler
04-26-2013, 05:27 PM
Larry beat me to it, shows up real well on targets

Bullshop
04-26-2013, 07:25 PM
I thought so too. Drop the load a grain and shoot another target. If the holes are round we learned something. Another way to try is add a grain and shoot another target if they dont hit it or if the holes are more oval we learned something.

45 2.1
04-27-2013, 10:08 AM
I thought so too. Drop the load a grain and shoot another target. If the holes are round we learned something. Another way to try is add a grain and shoot another target if they dont hit it or if the holes are more oval we learned something.

I'll save you some trouble.... they begin to keyhole when you reduce the velocity to about 1350 fps. Of course, going up in velocity will make them quite stabil.... but that depends on some things like loading them properly.

Bullshop
04-27-2013, 11:44 PM
I guess it will depend on the twist. My current rifle has a slower than normal for caliber twist of 1/10" There will be other things that effect it as well like boolit hardness and pressure. All powders are not created equal. How about barrel ware?
Another thing I was getting at is that, and I am not silly enough to say this will always happen to everyone but it did happen to me is that shooting the CM fairly soft in a milsurp barrel with a fast powder at some point near the upper end of pressure for the powder the boolit would make a buzzing noise in flight and never touch the target. Any of those boolits I found in the berm were bent in a C shape. I cant confirm if they bent in flight and that is what made the buzz noise or if impacting the berm is what bent them.
Maybe I was just pushing them beyond the alloy limits and they were loosing the groove but I did not get leading that will usually result in such a case.
I do know that I have heard the buzz noise before when shooting long 45 cal rifle boolits with too slow a twist for the length of the boolit.
Those boolits would group great at 100 yards but somewhere at about 250 to 300 yards they would loose stability and begin to buzz. At that point they would greatly increase in drift and drop. A buzzing boolit offers greater side area for wind to push against and frontal area to add drag.
I dont understand why the 6.5 CM would begin to buzz at a certain pressure/velocity like the long 45 with insufficient spin when the 6.5 has adiquate spin. If not inadiquate spin then something else, what?

BlackpowderSweden
04-28-2013, 01:09 AM
So far I have only tried 15, 16, 17gn of R123 and 16gn seemed to be the sweet spot accuracy wise.
Then I have tried different lubes, rcbs green, Lee la, ls alox 2500, ls caranuba red, and the rcbs green have shot the tightest Groups.
Then I have tried different alloys, first 20% lino 80% pure lead for about 16brinell , then tried 3% antimon alloy for about 11 brinell, the harder alloy had the better accuracy.
My Gun has a New barrel with a 1-8" twist, chambered it with a clymer standard reamer, wich seems to have a Long lead.
I Think that my stability issues are beqause the bullet is to Heavy.

JeffinNZ
04-28-2013, 03:20 AM
Ah yes, the oval boolits holes showing the presence of the Cruise Missile.

Tom Myers
04-28-2013, 09:19 AM
I was using 16gn old Norma R123, similar burnrate to 2400?
Velocity was about 1650fps .



My Gun has a New barrel with a 1-8" twist, chambered it with a clymer standard reamer, wich seems to have a Long lead.
I Think that my stability issues are beqause the bullet is to Heavy.

Twist rate is influenced by length (although length also influences weight)
Scaling out the image of the Cruise Missile bullet, the length appears to be close to 1.378 inches long.

Although this calculation formula is only a guideline, I have found it to be a reliable indication of the velocity required to adequately stabilize a bullet base upon caliber and twist rate.

V = ( L * T ÷ D² ÷ 3.5 )²

To find velocity, "V"
Enter 1.378 as length ,"L"
Enter 8 as twist, "T"
Enter 0.267 as diameter, "D"

The minimum calculated velocity for optimum bullet stabilization is 1952 fps.

You can eliminate the calculations by using this online Twist / Velocity / Length (http://tmtpages.com/twistrate.htm) calculator.

Hope this helps.

Bullshop
04-28-2013, 10:14 AM
"I Think that my stability issues are beqause the bullet is to Heavy. "

Or are they bending? Do you hear a buzzing sound from the boolits in flight? Maybe that very slight tipping would not cause the buzz noise. Once they start wobbling enough to print very elongated holes on the target they do buzz.

45 2.1
04-28-2013, 11:50 AM
The minimum calculated velocity for optimum bullet stabilization is 1952 fps.

It surely does............. Oldfeller wanted a heavy hunting boolit for the 6.5 Swede and this is what we came up with. Some other folks besides me have taken the Cruise Missile well past what has been discussed on the forum here.


"I Think that my stability issues are beqause the bullet is to Heavy. "

Or are they bending? Do you hear a buzzing sound from the boolits in flight? Maybe that very slight tipping would not cause the buzz noise. Once they start wobbling enough to print very elongated holes on the target they do buzz.

Stability issues come from trying too low a velocity. See the above post by Tom. Full tilt the Cruise Missile will hold 2 MOA providing its loaded correctly and the shooter is up to it..

BlackpowderSweden
04-28-2013, 12:22 PM
I will try for higher velocity with XMP5744 and Norma200

45 2.1
04-28-2013, 12:37 PM
This thread may help you some:
http://castboolits.gunloads.com/showthread.php?70923-Milk-Jug-300-Yard-6-5-Swede

swheeler
04-28-2013, 12:50 PM
I think you will find that bullet to be closer to 1.260" long checked, by Toms calculator with 1:8 twist and .267 the velocity needed would be 1632 fps.

Dutchman
04-29-2013, 02:20 AM
Hej

50 yd from a scoped Carl Gustaf m/38. Load was 13.8 grains 2400. Bullet diameter is .267". This batch of Cruise Missiles are from one of the original single cavity molds purchased from Gardner's Cache in Illinois http://gardnerscache.com/6_5mm_170_fp_g_c.html .

I did try upping the load 1 gr at a time but the tilting did not diminish. I've not put a lot of time into this bullet. The idea of sizing the nose separately from the body seems way too labor intensive for my tastes. There may be hope for this bullet as cast from the original mold but the 2 cavity molds sold now by Mid-South are so much oversize as to be utterly useless in 6.5x55.

I do intend on working a little bit more with the Cruise Missile this summer.

http://images52.fotki.com/v727/photos/2/28344/157842/65x551701382400ab-vi.jpg

Scope is Tasco 6-18x44 target scope. Best ammo testing platform for 6.5x55 :).

http://images56.fotki.com/v1602/photos/4/28344/9895637/DSCF1959p-vi.jpg

JeffinNZ
04-29-2013, 03:51 AM
Departing at 1750fps the CM will hold 2 MOA in my Carcano BUT the holes are always oval. Wallabies didn't seem any the wiser.....

Bullshop
04-29-2013, 09:42 AM
If these are reaching the required rotational velocity for stability and I see buy the numbers posted they are could someone please explain the oval holes in the target?
Since the ovals are in random directions the angle of entry is not a valid reason so dont go there.

Tom Myers
04-29-2013, 10:12 AM
If these are reaching the required rotational velocity for stability and I see buy the numbers posted they are could someone please explain the oval holes in the target?
Since the ovals are in random directions the angle of entry is not a valid reason so dont go there.

My understanding of the process may not be correct, but I believe that oval holes are not always an indication of bullet instability. A bullet may be stable but the nose can be oscillating or precessing about the axis of the bullet path.

The oscillation can be cause by launching errors such as bullet/case run-out or bullet base/barrel crown irregularities causing the misalignment of the bullet axis to the flight path axis.

When a bullet becomes unstable, the rotational force has slowed down to the point that it is unable to prevent the bullet from tumbling due to either oscillation or turbulence.

While in the pits, pulling targets at the 1000 yard range, I have seen some quite respectable scores produced with holes that were randomly orientated ovals. However, I would imagine that if the bullet had been launched without the oscillation or precession, the scores would have been even better. Another interpretation of the oval holes at the 1000 yard range could be that the bullet was just on the threshold of becoming unstable at that range.

45 2.1
04-29-2013, 10:28 AM
There are a lot of assumptions here: 1) 8 twist.... Metric twist rate of 200mm gives 200/25.4= 7.87", 2) the boolit stays at the unfired length you measured.... recover some and find out for yourself, 3) the formula is based on what form shape of bullet, 4) incorrect results based on calculated answers.

I can tell you more velocity produces round holes, so the formula has some problems it seems.

swheeler
04-29-2013, 10:34 AM
If these are reaching the required rotational velocity for stability and I see buy the numbers posted they are could someone please explain the oval holes in the target?
Since the ovals are in random directions the angle of entry is not a valid reason so dont go there.

Maybe just a quirk of this bullet, design flaw?

Bullshop
04-29-2013, 12:17 PM
So does the oscillation increase with range or is it stable for the bullets flight? That question is directed at a bullet with adiquate rotational velocity and not one that is beginning to loose stability due to inadiquate rotational velocity.
In so many words because of this thread via email I have been called a lier because I stated that I have heard the bullet buzz in flight at the point of becomming unstable due to insuffisiant rotational velocity for the boolit length.
In the case I mention this particuler boolit grouped very well at 100 yards but in shooting it at 500 yards somewhere inbetween 100 and 500 yards it became unstable and likely bagan to tumble and would radnomly scatter in a 50 yard area in the vicinity of the 500 yard target. Somewhere during its flight the instability caused an audable buzz that could easily be heard if one paid attention.

swheeler
04-29-2013, 02:32 PM
Daniel I believe what you witnessed may have actually been "nose Up" flight, with the side of the bullet exposed to air/wind resistance. This is more likely caused by the fast twist of the Swede and forward momentum decreasing faster than rotational momentum, the bullet trying to follow angle of departure and at 500 yards coming in nose up, exposing the side of bullet to air resistance, that'll give you the whirlly noise. As for someone calling you a liar by email, block them, I've had to block phone numbers to get peace and quiet from knowitalls before;)

Larry Gibson
04-29-2013, 07:41 PM
The "buzz" of bullets being unstable in flight is easily heard, even by someone who has become as deaf as I. Don't sweat the small stuff Dan, we know who probably sent the email........

The problem with long cast bullets in fast twist like the 6.5 Swede is at the velocity required for stabilization the RPM is already over the RPM threshold.....basically a no win situation......just an uniformed unitentional design flaw. May indeed also be some "bending" of the bullet due to rotational torque on the bullet nose as it exits the muzzle(?) which has all been previously discussed.

I'm in Dutch's camp; I find the gyratations of sizing the oversized driving bands and the nose down enough so the bullet will chamber when seated so the GC is at the base of the neck is more than I want to do, especially when cast bullets of 129 - 150 gr weight work well.

Larry Gibson

swheeler
04-29-2013, 08:16 PM
That's what I think too, design flaw. The little 6.5 Kurtz Buckshot designed seems to shoot just fine for everybody.

BlackpowderSweden
04-30-2013, 06:00 AM
"I Think that my stability issues are beqause the bullet is to Heavy. "

Or are they bending? Do you hear a buzzing sound from the boolits in flight? Maybe that very slight tipping would not cause the buzz noise. Once they start wobbling enough to print very elongated holes on the target they do buzz.

No, I've not heard any buzzing with this rifle and bullet.
I think the bullet is yawing a little, with this long bullet, a minor yaw will be very easy to spot.
I shoot it at 200m as well, and then it is even more visible on all bullet holes, and accuracy was not so good.

Bullshop
04-30-2013, 09:25 AM
So there is my answer, the oscillation increases with range. That now brings up another question, at some range will the oscillation become bad enough to begin the buzz? I think that going by what Larry and others said that answer is yes.
I also think that shortly after the detectable buzz begins at some further distance that boolit will tumble.

Good Cheer
04-30-2013, 09:44 AM
This topic is getting me worked up...
Got a beautiful 6.5x53R with a destroyed bore. Had bought one of these molds to try out in it. Reckon I'd best see about getting it fixed.

Larry Gibson
04-30-2013, 10:34 AM
So there is my answer, the oscillation increases with range. That now brings up another question, at some range will the oscillation become bad enough to begin the buzz? I think that going by what Larry and others said that answer is yes.
I also think that shortly after the detectable buzz begins at some further distance that boolit will tumble.

Concur.

Larry Gibson

BlackpowderSweden
04-30-2013, 03:14 PM
What load of XMP5744 would you estimate for a velocity of 1700fps?
I have shoot some amazing groups with 26gn XMP and 130gn jacketed bullets.