Does the shoulder stabilization negate any consideration of the bullet "going to sleep"?
Seems to me it would, and an FN solid is the best thing since flake powder. Due to this self correcting feature, with a proper truncated cone FN with a big meplat, any minor angle of attack departure from zero is self correcting with an FN.

Seems the elephant hunter striving to get as close as possible would want nothing but an FN solid.

Who in his right mind would use a round-nosed solid for any job requiring a "solid"?

Pondoro

Ha Ha.

B

Pondoro was on the right track with his criticisms of bullet shape, but he was too busy chasing native boys in his birthday suit and turban to get to the right answer.

Let us limit this to the modern day hunter who can't afford to have a bull run off from a deviated or insufficiently penetrating solid, especially the guy who wants to use a reasonable rifle that doesn't necessarily pack all the "Taylor Knock Out Value" to knock one out with a near miss of the brain.

To knock an elephant out with a near brain miss: I call that "gay bashing with Taylor."

I don't know RIP. Maybe you could talk Saeed into upping your post count to 10 or 11 thousand as a Cristmas present.

Will,
I knew that would yank your chain. If it is any consolation, they are running me out of Kansas tomorrow, back to Kentucky, and I wouldn't fire Miss USA either!

Rip,

FN solid? Are you intending to refer to North Fork solid [or www.gscustom.co.za solid]?

Jack,
It is about time you got this straight.

GSC makes the FN: Flat Nose

North Fork makes the FP: Flat Point

Since GSC was doing it long before North Fork, "FN" has become the generic term. Many people mistakenly call the North Fork an "FN" as you are doing. Since North Fork has established "FP" as the designation, then "FP" would be properly used to refer to a North Fork monometal copper solid.

To my knowledge, GSC was/is the pioneer of the monometal-copper-drive-banded-Flat-Nosed-Truncated-Cone solid, and the whole world should be eternally grateful.

If anybody can correct me on this, then have at it.

Now to publicize another great new invention by GSC: THE .395 CALIBER SP, HV, and FN.

What does Bridger call their solid?

Btw, first release...here's one (a .475 500gr) that came a couple inches shy of fully penetrating a cape buff lengthwise...



Canuck

quote:

To my knowledge, GSC was/is the pioneer of the monometal-copper-drive-banded-Flat-Nosed-Tuncated-Cone solid, and the whole world should be eternally grateful.

ps: btw, on this point I agree wholeheartedly.

quote:

Originally posted by Canuck:

quote:

To my knowledge, GSC was/is the pioneer of the monometal-copper-drive-banded-Flat-Nosed-Tuncated-Cone solid, and the whole world should be eternally grateful.

ps: btw, on this point I agree wholeheartedly.

Canuck,
Thanks for pointing out the truncation in my misspelling of "Truncated."

I believe Bridger's are called by "FN" designation by the maker himself.

I like to call them "BBFN" solids: Bridger Brass Flat Nose

quote:

I like to call them "BBFN" solids: Bridger Brass Flat Nose

I like it. I will call them the same henceforth (unless John decides he wants to call them something else!).

Cheers,
Canuck

quote:

Originally posted by Canuck:

Canuck

Second release of Canuck's recovered .475/500gr BBFN:
Nice closeup of some nose deformation and rifling engravure. Was it a Texas Heart Shot or front entry? Did it hit bone early on or late in its course?
Please and thank you.

Is not the Barnes banded solids essentially the same as Bridger's?

No, Will, it is not. It is an ogived FN, like you just filed the nose flat on one of their Round Nose Brass solids.

They are not banded either. They have extra cannelures cut into a shank that is sub groove diameter.

quote:

Second release of Canuck's recovered .475/500gr BBFN:
Nice closeup of some nose deformation and rifling engravure. Was it a Texas Heart Shot or front entry? Did it hit bone early on or late in its course?

It was a "bullet test" on a deceased buff. Frontal entry. Bullet fired approx. 6 feet from target. Very satisfying carcass "jump" on bullet entry (ahh, horsepower). Bullet hit spine very shortly after entering, and penetrated approx 12 to 18" of bone (not autopsied -- we went huntin' instead -- estimated from best guess of bullet path). Bullet found in rear ham, a couple inches shy of complete penetration.

2500fps muzzle velocity, 1-14" twist re-bored Ruger barrel.

Cheers,
Canuck

No flies on a BBFN.

quote:

They are not banded either. They have extra cannelures cut into a shank that is sub groove diameter.

Well, the shank of NF's are subgroove diameter. And the bands are supposedly the groove diameter, or subgroove diameter in most cases.

There may be more bands in the case of Barnes but it is the same idea. The Bridger are the same.

The requirement for a drive band bullet is an ogive that meets the bullet shaft at barrel bore diameter and continues on to become the start of the base / heel/ boat tail, still at barrel bore diameter. In the shaft area are drive bands that are of barrel groove diameter to seal the gas driving the bullet. The combined area of the drive bands is less than half the total area of the shaft. The bullet is aligned by and runs on the faces of the lands. Only the drive bands are engraved by the rifling. No engraving occurs on the ogive of the bullet.

DRIVE BAND BULLET



GROOVED BULLET




DRIVE BAND BULLET




GROOVED BULLET

Gerard,

It is there any allowance ever made for barrels that are slightly oversized or undersized? I would imagine that this a nightmare for a bullet maker, especially for the solids.

If the barrel grooves are slightly undersized, will the bands just bend over to accommodate this?

Will,
This is the beauty of a drive band bullet. If the bore and/or groove dimension of the barrel is under size, there is still much less engraving to be done on a drive band bullet compared to a grooved or smooth bullet. Pressure remains much lower. To prove a point for ourselves, we have fired a 7mm HV bullet in a 270 Win. Accuracy was terrible and it was a mission to get chambered but the primer pocket did not even loosen up.

If the barrel is over size in the grooves, you will get gas leakage regardless of what kind of bullet is used, but a drive band bullet will be faster through the throat with less flame cutting than other types. We have a fair number of customers where we have identified oversize bores and for them we make bullets to the correct size. Our standard HV / FN bullet range is good for up to .015mm (.0006") oversize barrels.

/

Alf,
You ask:

quote:

Do we have evidence that having driving band bullets are in fact "better" than bullets with grooves cut in them?

Better in what way specifically. What are you looking for?

quote:

what would happen if you take a grooved bullet, add more grooves or making grooves larger leaving then very thin "bands" do we not just simply end up with a banded bullet?

Yes you do, provided you also terminate the ogive at a diameter equal to the bore diameter of the barrel.

quote:

Some of my rifles will not accurately shoot GSC HV's

Send me an e-mail with the details of rifle and bullet or post it here and I will try to help. There is always a reason for bad groups.

quote:

"drive band bullet will be faster through the throat with less flame cutting than other types"

By what means was this tested or validated??

Consider the full sentence below to bring the part you question into context.

quote:

If the barrel is over size in the grooves, you will get gas leakage regardless of what kind of bullet is used, but a drive band bullet will be faster through the throat with less flame cutting than other types.

Flame cutting is greatly increased when gas escapes past the bullet as it travels down the bore. It is more important to control this than the often quoted volume of propellant that is cited as the cause of throat erosion. The higher the pressure, and the more time the under size bullet spends traversing the throat, the worse the flame cutting will be. Due to the decreased engraving pressure of a drive band bullet (amongst others, no ogive to engrave and put the brakes on the accelleration of the bullet), pressure in the throat is reduced and the bullet spends less time in the throat. (It is faster through the throat thus reducing the flame cutting.)

quote:

Does the speed of the bullet in the throat have an effect on the rate of barrel deterioration at the throat? I always thought and so do engineers that build and design cannon and arms barrels that propellant type, composition and absolute adiabatic caloric value of the propellant are the major determinants in flame erosion at the throat.
( And they have evidence to prove it)

Actual velocity of the bullet through the throat is not relevant, it is temperature and pressure that primarily determines flame erosion and secondly the volume and particle characteristics of the propellant. Flame erosion is therefore mistakenly associated with high speeds. If increased speed can be had at standard peak pressure levels and with reduced temperature and pressure in the throat, speed is not the culprit here. New rules.

Propellant volume and particle characteristics we can control by choosing propellants with more circumspection. The primary factor of temperature and pressure is controlled by choosing a bullet that allows the least amount of gas leakage and by reducing engraving pressure and thus temperature and pressure in the throat.

From a bullet choice point of view:
The best situation will be with a drive band bullet that fits the bore and groove dimensions of the barrel properly.
Next best is a smooth or grooved bullet that fits the groove dimension of the barrel properly.
Worst is a smooth or grooved bullet that is under size for the groove dimension of the barrel.

Note that all this addresses the issue of throat erosion and barrel wear only.

/

quote:

Originally posted by Will:

There may be more bands in the case of Barnes but it is the same idea.

No they are not. The barnes bands are so wide that the material displace by engraving the rifling cannot just be pushed back into the groove behind the band, so your barrel must flex instead. GS and NF have thin bands and the band material from engraving the rifling easily displaces to the groove behind the band.

So, you can shoot GS and NF driving band bullets in a double, but you cannot shoot Barnes in a double. (If you already have, well, ...).

By the way, last time I called bridger, John was unavailable but the girl told me they were completely out of the bullet business.

quote:

Originally posted by Gerard:

... Worst is a smooth or grooved bullet that is under size for the groove dimension of the barrel.
Note that all this addresses the issue of throat erosion and barrel wear only.

That would be by definition a Barnes TSX or Barnes Pseudo-banded-pseudo-FN-brass Solid. No problem if a rifle shoots the TSX accurately, except that the rifle will need to be rebarreled sooner.

However, the ogived-FN-brass is not as efficient a penetrator as a truncated-cone-copper-FN, for several reasons, IMHO/SWAG.

500grains,
The Bridger Bullets were always so "on-again-off-again" that I never knew what to think.

Off-again now, you say:

That is sad. Hopefully it is only a temporary refocussing of business.

I am very glad I have enough .475 500gr solids to last me a LONG time though!

Cheers,
Canuck

quote:

However, the ogived-FN-brass is not as efficient a penetrator as a truncated-cone-copper-FN, for several reasons, IMHO/SWAG.

RIP,

At least you added a "IMHO" to this fanciful prejudice of yours.

Last year I saw a Barnes Banded FN Solid that had been driven diagonally clean through a bull elephant on a raking body shot. The rifle was a .450 Dakota.

The only reason the bullet was recovered was because it had struck a large tree on the other side of the elephant. The bullet had to be hacked out of the tree trunk from a depth of several inches.

That's enough penetration for me. I'm now a believer in the penetrating ability of Barnes Banded FN solids.

Plus the Barnes will feed in a bolt rifle.

quote:

Plus the Barnes will feed in a bolt rifle.

Just to be clear, are you implying other's don't feed in a bolt rifle??

FWIW, I have loaded GSC FNs, Bridger FNs and Northfork CPS's and have never had an issue with feeding.

Cheers,
Canuck

MR,

This just goes to show that you are toatlly unaware of the importance of twist rate, moon phase, and other critical factors concerning penetration and K.O. value!

Like I have said before, I am now also a beliver in the flat nose, which is most likely the dominant factor in the increased penetration, not bands, not mono's, not twist, etc.

I suspect Woodleigh will follow suite at some point. If the flat nose will feed (irrelevant for doubles) then have at it, assuming excessive(?) penetration is what is needed.

Have a great Holiday Season.

quote:

Originally posted by Will:
MR,

This just goes to show that you are toatlly unaware of the importance of twist rate, moon phase, and other critical factors concerning penetration and K.O. value!

Like I have said before, I am now also a beliver in the flat nose, which is most likely the dominant factor in the increased penetration, not bands, not mono's, not twist, etc.

Yeah, but can you PROOOOVE it, or is this just a gut feel.

/

Meplat diameter looks like a trade off.

Smaller meplate / better stabilization in air / less angle of attack.

Larger meplate / better stabilization in elephant, tree, Iron Buff, etc.

Alf,
I am all ears and await an opinion from Gerard Schultz or Mike Brady.

If they do not present such an opinion shortly, I am sure you will have found the proper equations to solve for the answer before New year's Eve.

Keep up the good work.

/

This is very interesting. On the surface it seems that smallest meplat diameter would constantly change along with rate of deceleration.

Meplat diameter is a trade off between what works best on the target (as large and sharp edged as possible) and what will feed reliably in the bolt rifle in which the bullet is likely to be used. Bullets that will be used in doubles only can have larger meplats and, once again, it is important to follow the bullet maker's recommendation of bullet/caliber choice. Interestingly, a larger meplat is created as the bullet penetrates, if the speed is high enough and if the bullet is made from copper not brass. This is good for creating a larger volume wound channel. It requires dropping some weight off the bullet to get the speed up and here the SD (slow and heavy) freaks lose out.

The ones on the left were stable and went deep - much better than the smaller diameter ones.

/