I have heard about Woodleigh's past run of 900 grain .585 bullets, but have been unable to find any. Does anyone have any they would be willing to sell, or know of any seller/bullet maker where I can get 900 grain jacketed or solid bullets? Thank you.

Ken-I have two Karl sent me . Ask Huntingtons,
maybe they'd get them in from Australia.
Sometime will shoot them in 585HE to see
what it'll do.Ed

I bought a lifetime supply when the opportunity arose, but I do not wish to diminish that supply.

quote:

Originally posted by 500grains:
I bought a lifetime supply when the opportunity arose, but I do not wish to diminish that supply.

Where did you get a 1x10 twist .585 barrel, Dan? Just wondering, as I have never seen one listed.. and, according to your well expereinced statements, anything slower is worthless, and, well, you might as well give those bullets away, without a 1x10 barrel

jeffe

Jeffe,

All we are saying is give twist a chance. (Beatles melody : "Give Peace a Chance")

The A-Square manual shows data for the .577 NE with a 1:30" barrel.

A-Square used a 1:12" twist on the .577 Tyrannosaur, to develop that impressive data for 750 grain bullets.

They shot it enough to know it worked well.

10" or 12" it's all good.

Ye Olde Slowe Twiste Barrels are not junk.

However, they can be improved upon if a rifle builder is not so silly about the Greenhill formula.

Pressure and velocity changes between 7.5" twist and 14" twist artillery barrels are LESS THAN ONE PERCENT.

ACCURACY differences between a 10" twist and a 15" twist barrel are LESS THAN 0.1 MOA at big bore hunting rifle ranges.



Where is the beating a dead horse emoticon when you need one?

**********************************************

Jeff, I will be delighted to discuss twist with you further after you get some experience shootingsome animals on which penetration matters.

Kenneth,
You better use faster than 1:30" twist with those .585-caliber/900-grain Woodleighs if you can find them.

A .585/750 grainer has SD = .313

A .585/900 grainer has SD = .376

Yep, better think about a 10" or 12" twist. The faster twist selection allows greater chances of success with a greater variety of bullets, always better with the long/heavier than usual ones, and never a problem with the standard or shorter than standard ones, in a big bore hunting rifle.

It was a special run by Woodleigh, eh?

I fired a dozen or so of them from Mitch Carter's .577 T. Rex. 900 grains at 2200 fps taught me about TORQUE and how to hold onto the rifle like I meant it.

RIP

I believe you are far closer to understanding twist, with your statements of Give Twist a chance .. I nearly spit coffee on my keyboard.

and "if shot enough, there would be some difference" ... THose are fair and level headed statements.

quote:

Originally posted by 500grains:
Jeff, I will be delighted to discuss twist with you further after you get some experience shootingsome animals on which penetration matters.

Dan,
and I would be delighted to hear your opinions on gunbuilding, pending the same circumstance. After all, there's more to hunting or gunsmithing than placing an order, no?

as usual, though, you avoid the question, what TWIST is your 585?

Let's see, on terminal ballistics, Which group would you think has more field expereince and customer feedback...

Art Alphin,


HH, Purdy, Rigby, Jeffery, and, oh Schuler?



Dan,
the offer stands, I'll give you $100 for either your too slow twist doubles, or your too slow twist 585 nyati... after all, according to YOU, anything less than 1x10 is WORTHLESS...

jeffe

quote:

Originally posted by jeffeosso:
RIP

I believe you are far closer to understanding twist, with your statements of Give Twist a chance .. I nearly spit coffee on my keyboard.

and "if shot enough, there would be some difference" ... THose are fair and level headed statements.

jeffe

Thanks, Jeffe. I think you are making progress toward full understanding too. Hang in there. Soon you will get it. Extra twist in a big bore hunting rifle can only help, as long as you don't go any faster than 1:7.5".

quote:

as long as you don't go any faster than 1:7.5".

That is not a twist rate. That is a thread pitch.

Hog Killer

quote:

Originally posted by 500grains:
I bought a lifetime supply when the opportunity arose, but I do not wish to diminish that supply.

Dan, that is a post I would expect from a 6 year old. The same as them going: "nan,nana,nan, nana, I go mine and you can't have any". Shame on you.

The man was asking for a source. Not what was in YOUR inventory.

Hog Killer

My 585 has 1 to 22 twist. It stabilizes fine, penetrates ok at my speeds. The difference
between pressures of a 1 to 10 and my 1 to 22
is a inverse function of the difference in velocities with same powder load.
I, from testing over the years, know if I had
1 to 10, my velocity would be over 5% less
than 1 to 22. Ed.

Gentlemen,

My .585 only had a 1:18 twist and it only got 2.5 to 3.5 feet of penetration on body shots using solids. Obviously it needed a faster twist. (velocity was 2250 fps, 750 grains, Woodleigh and TCCI RN).

Oh Crap back at it again! 1:10 twist making any difference is pure BS and you guys know it. Try shooting the animal in the right places with good bullets and you won't have to worry about this crap. BTW my .585 Nyati and the .600ok have 1:18 twists and I have and have had no complaints about penetration. Don't think I'll hear any either. -Rob

/

how is mitch?

I only have two.........given to me by Karl and I do not want to part with them

quote:

Originally posted by ALF:
500 gr:

Robgunbuilder is correct in that there is no evidence that altering projectile rotational velocity by changing rifling twist in an already stable projectile in flight has any effect on projectile penetration in dense media.

Yes, there is. Since you do not buy into supercavitation, then you must be an adherent to the shoulder stabilization of bullet penetration. More yaw = poorer shoulder stabilization. Less yaw = better stabilization and remaining stable longer.

Unfortunately, relatively few people distinguish between bullet stability in air versus bullet stabillity in an animal. But those are two different worlds.

The shoulder stabilization concept
is born out in real world, but shoulder stabilization isn't much affected by spin if slug is stable at the target, but affected by
the shape of that shoulder.IE, flat large diameter bullet fronts give sharper shoulder,
and penetrate better than
rounded shoulders that come with round and spitzer points.The penetration of Bridger flat
nose is huge at slow twists Rob and I use
in 12GA FH, In my case clear through
a 5-6 foot bundle of hardwood.Ed.

/

Some guys have so little regard for twist that they might as well shoot smooth bores.

Alf- Well written and clear. Your arguments are sound and your observations quite valid in my opinion at least. However, my friend I doubt you will convince the "experts" here with mere scientific facts. They want to believe that a magical 1:10 twist will over stabilise a bullet ( whatever thats supposed to mean) resulting in superior penetration irregardless of about 6 other much more important factors.I agree with you and Ed in that the only rational for the penetration of flat point bullets is their shoulder stabilzation effect in dense media which is geometry, density , velocity dependent and spin independent. -Rob

Hey!
I like the fast twist because it allows better use of the long monometal bullets for hunting, and things like 2.5" long target bullets in the 500 A2.

I have had great success with the 10" twist pushing 750 grainers to target accuracy with the slow 2150 fps MV of my 500 A2 out to 942 yards in the cow pasture.

The rotational speed of this would be similar to 15" twist in a 50 BMG.

The same 10" twist barrel with .510/570 grain FN solid at 2400 fps will reliably penetrate 8 feet of buffalo from rump to departing neck. If the head were lower it would probably exit through the skull, Texas brain shot style.

I found no difference in penetration ability of 10", 16" and 18" twist .475 rifles with the same FP/FN solid bullets loaded to similar velocities for comparison in the Iron Buffalo bullet trap: varied twist with 2100, 2300, and 2500 fps.

Agreed shoulder stabilization has nothing to do with twist, nor does a badminton birdy.

I remain a champion of fast twist in the over .40 bore but I will concede some ground and allow as slow as a 12" twist, since I have had such good luck with them.

The main thing is better bullet variety/flexibility.

Nothing gets my goat worse than wanting to use a longer bullet in a big bore and not having enough twist to handle it.

I would always rather have more than enough twist in a hunting rifle, than not enough.

The fussy 1000 yard target shooter should go with the twist only fast enough to stabilize that one special bullet.

Just for fun then: I'll change my signature line to approve 12" twist, especially since all my .375's, some of my .416's, and .458's too, are that twist.

Never any need for anything faster than 10" or 12" twist in any hunting rifle of .375 or larger caliber.

That is a near certainty.

quote:

Originally posted by Robgunbuilder:
I agree with you and Ed in that the only rational for the penetration of flat point bullets is their shoulder stabilzation effect in dense media which is geometry, density , velocity dependent and spin independent. -Rob

Rob, you mean like this??

1/4" steel plate @ 100yds



1.5" projectile, with a 1.125" meplat. AND ZERO SPIN.

Hog Killer

RIP - yaw has something to do with twist.

More yaw => earlier tumbling => less penetration.

Faster twist => less yaw.

However, Norbert says that fast twist penetrates deeper because the fast twist keeps the supercavitation bubble stable longer.

Sadly I will not be doing a fast twist / slow twist penetration test on elephant in 2007 because Jeffeoso has backed down from providing the rifle (on loan). Not sure if he does not wish to see the results, or if he does not wish me to see the gunsmithing!

quote:

Originally posted by 500grains:
Some guys have so little regard for twist that they might as well shoot smooth bores.

Dan,
do you actually believe this, or is it just "insult them" time?

just a question....


though, since you equate 1:18 and 1:15 as "smoothbores" , here's your moment to make a stand.. put up, or shut up...

Where would you like me to send that $100 for my 585 nyati with the "smoothbore" ?
jeffe

quote:

Originally posted by jeffeosso:


just a question....


though, since you equate 1:18 and 1:15 as "smoothbores" , here's your moment to make a stand.. put up, or shut up...

Where would you like me to send that $100 for my 585 nyati with the "smoothbore" ?
jeffe

What are you talking about? $100 for what?

500/Jeff
I see were well rested.. I'm just wondering if were going tho see a new "Twist" in this thread..
AK

Dan,
The minor yaw is corrected by the shoulder stabilization regardless of twist rate. Right?

The faster twist may have more nutation or "cone motion" if the bullet center of gravity is not concentric to form.
Thus a LESS THAN 0.1 MOA accuracy decrement with the 10" twist versus the 15" twist.

IT DOESN'T matter in a hunting rifle!!!

More than enough twist is always better than not enough twist in a big bore hunting rifle using appropriate bullets.

quote:

I found no difference in penetration ability of 10", 16" and 18" twist .475 rifles with the same FP/FN solid bullets loaded to similar velocities for comparison in the Iron Buffalo bullet trap: varied twist with 2100, 2300, and 2500 fps.

Then why use a faster twist?

I think it is important to differentiate your reference to the 500A2 / 50 BMG...you are introducing two different points here. First there is twist for "acceptable target shooting" and then there is twist for "acceptable hunting penetration".

I would agree that a 2.5 inch 750 gr. target bullet in either the 50BMG or the A2 might be better served with the 10" twist for accuracy purposes. It is an extremely long bullet.

On the other hand you say that a 10 inch twist 570 gr hunting bullet penetrates 8 feet of the iron buffalo. Would a 12 or 15" not be comparable in penetration ability? You stated above that you found no difference in the .475 bore then what makes the .510 so unique that it is any different?

quote:

Originally posted by akrange:
500/Jeff
I see were well rested.. I'm just wondering if were going tho see a new "Twist" in this thread..
AK

akrange:

I have conceded some ground and am now happy with 12" as well as 10", even on a 500 A-Square.

That is a new twist of sorts, for me.

quote:

Thus a LESS THAN 0.1 MOA accuracy decrement with the 10" twist versus the 15" twist.

I think your logic here might be off a bit. IIRC this variation of 0.1 MOA was determined from a "benchrest" rifle. These rifles have a very small standard deviation and variance between shots. You can't accurately say that your big bore is as consistant as a benchrest rifle can you (excluding 50 BMG)?

/

quote:

Originally posted by JMJ888:

quote:

I found no difference in penetration ability of 10", 16" and 18" twist .475 rifles with the same FP/FN solid bullets loaded to similar velocities for comparison in the Iron Buffalo bullet trap: varied twist with 2100, 2300, and 2500 fps.

Then why use a faster twist?

I think it is important to differentiate your reference to the 500A2 / 50 BMG...you are introducing two different points here. First there is twist for "acceptable target shooting" and then there is twist for "acceptable hunting penetration".

I would agree that a 2.5 inch 750 gr. target bullet in either the 50BMG or the A2 might be better served with the 10" twist for accuracy purposes. It is an extremely long bullet.

On the other hand you say that a 10 inch twist 570 gr hunting bullet penetrates 8 feet of the iron buffalo. Would a 12 or 15" not be comparable in penetration ability? You stated above that you found no difference in the .475 bore then what makes the .510 so unique that it is any different?

That was 8 feet of real buffalo: Bison, with the 500 A2.

The .475 tests with twist were "Iron Buffalo" or wood and water, and more like 7 feet there.

Faster twist has no significant pressure, velocity or accuracy decrement down to 10" rate, I am sure.

It is more flexible in bullet usability.

15" is optimum for 750 grainers in the BMG.

10" or 12" is optimum in the slower 500 A-Square with the same bullet.

There is a lot of silly fear of fast twist out there.

quote:

Originally posted by JMJ888:

quote:

Thus a LESS THAN 0.1 MOA accuracy decrement with the 10" twist versus the 15" twist.

I think your logic here might be off a bit. IIRC this variation of 0.1 MOA was determined from a "benchrest" rifle. These rifles have a very small standard deviation and variance between shots. You can't accurately say that your big bore is as consistant as a benchrest rifle can you (excluding 50 BMG)?

Of course I can, I am that good, and so are my 10" twist McGowen .510, .505, .475, and .423 caliber barrels!

You get the point. The benchrest rifle difference with twist would be more like 0.05 MOA, not 0.1 MOA. The hunting-range-accuracy, pressure, and velocity differences are negligible between 10" and 15" twist in a big bore.

I am willing to compromise at 12" twist. A new twist.

quote:

15" is optimum for 750 grainers in the BMG.

10" or 12" is optimum in the slower 500 A-Square with the same bullet.

By optimum are you referring to accuracy or penetration again. Given the 750 gr bullet selection for both cartridges I would agree with the above statement for accuracy purposes.

It however, does not add any creedence to the penetration point...which is the crux of the fast twist argument.

quote:

Faster twist has no significant pressure, velocity or accuracy decrement down to 10" rate, I am sure.

quote:

Extra twist in a big bore hunting rifle can only help, as long as you don't go any faster than 1:7.5".

Is it 10 or 7.5"...I can't see the scientific evidence here...seems to only add confusion, not eliminate it..

Where are Gerard and Chris Bekker when you need them! It's been a while since we had a 20 page rant. You know, this twist argument reminds me of a guy I used to work with. He had this old ass Ford pickup (or whatever) with a V6 in it. He said he was saving up to get the pulley to engage the other 2 pistons to make the engine a V8!! Ugh.

quote:

Originally posted by RIP:
Dan,
The minor yaw is corrected by the shoulder stabilization regardless of twist rate. Right?

No, actually I do not buy into the shoulder stabilization theory.

JMJ888:

You left the winking emoticon off the quote of the 7.5" twist comment.

You don't get a joke when you see one even with Mr. Winky? You have to learn the subtlties. Some of those Mr. Winky's have double entendre capability too.

The artillery studies did show no significant pressure or velocity changes with 14" down to 7.5" twist (less than 1%).

Optimum twist OF COURSE refers to accuracy, so stop getting confused about that too.

There is nothing proven about twist and penetration.

I am a stainless and synthetic type who likes monometal copper bullets, and the faster twist than the 18" to 30" stuff of yore. I want no part of marginally fast enough when it comes to twist. I want my rifles to work with all the bullets. Better more than enough twist than not enough twist, and that is a certainty.

I do draw the line at 10" just because I have used that so much and know it is great.

I am nowhere near as "Twist Timid" as some here are. At least I will dare to go with a 10" twist, and so far I am totally please.

What really got me started down the fast twist road was reading George Hoffman opine that he would prefer 12" twist for a .416 Hoffman, or any .416, instead of the slower traditional twist for the .416.

I am set in my ways. Stainless, synthetic, long bullets, and more than "enough" twist.

Use enough gun, and more than enough twist.

quote:

Originally posted by 500grains:

quote:

Originally posted by RIP:
Dan,
The minor yaw is corrected by the shoulder stabilization regardless of twist rate. Right?

No, actually I do not buy into the shoulder stabilization theory.

Good Lord deliver us!
We just recently got approval for shoulder stabilization here, after years of pooh-poohing it, and now you, 500grains, reject that???