I got the impression that they did back-to-back tests with everything the same (same rifle, same radar, same load, etc.) except the tip material. Changing only the tip changed their measured BC, so melting or otherwise, there seems to be something going on with it.

If that is really the only variable they changed, then there must be something to it.

quote:

Originally posted by jpl:
I got the impression that they did back-to-back tests with everything the same (same rifle, same radar, same load, etc.) except the tip material. Changing only the tip changed their measured BC, so melting or otherwise, there seems to be something going on with it.

If that is really the only variable they changed, then there must be something to it.

Did they publish their data, such that we can review it?

I think all of their data is on their web site.

Sam,

I still would like to see other manufacturers reproduce this effect and decide to switch to a more heat-resistant plastic tip.

I've become cautious about such claims, especially from folks who will gain financially.

AIU

Like I said, food for thought on the long range rounds. I shoot a lot of Sierra Match King and a little Berger, all metal no plastic, so it's more of a thought exercise at this point. I would guess if it does hold water we'll see a lot of new plastics being used, for example Sierra's TMK changing. If it doesnt, Hornady's new material may only last a while and the AMAX will make a comeback in the discontinued bullets.

I think it is still more theoretical right now even with Hornady's data being released. Could be no one has enough data to throw a BS flag.

(Except for 60 to 100 rounds a year, 2 or 3 matches, I don't shoot over 600 yards. My 1K rounds are a .223 loaded with a Berger or a .308 loaded with an SMK.)

I did some quick calculations using Bryan Litz's data and Hornady's ELD data.

First, note that Hornady has officially praised Bryan for his work and Bryan has noted that Hornady reproduced his BC data - almost exactly - using the Doppler radar technique. Both appear to know how to measure BC.

Hornady reports the G7 BC for the 208 gr ELD match bullet (new tip) to be 0.335.

Bryan had previous measured the G7 BC for the 208 gr Amax (old tip) to be 0.324...not a huge difference.

Indeed, if both were fired at 3000 fps at STP, the difference is only 4 inches vertical at 1000 yds (0.40 smoa). (I used Hornady's ballistic calculator.)

Given the usual mirage and shooter shake, it's very hard to hold consistently within 0.40 smoa circle at 1000 yds.

Finally, Bryan's measured G7 BC for the 208 gr Amax is 0.324 and his measured G7 for the 208 Hornady BTHP is only 0.319, essentially the same or a bit better for the Amax with the old plastic tip.

The BTHP - with the pointed copper tip - looks like the identical bullet to the Amax but without the plastic tip. If the tip-melting problem is significant, then the BTHP should have a significantly higher BC, not lower.

Bottomline:

IMO, the effect of the ELD tip does not appear to be that much, and possibly, negligible and of no practical significance, especially if you have an accurate BC for the bullet you are using.

Any further developments on this topic from Brian Litz or the other manufacturers, other than what's been posted on this thread?

In regards to how much heat is on the bullet tips as they are being fired.

There is a defense contractor in the Los Angeles area who is working on a new small arms projectile tracking system (for pilots to use when landing under fire).

They come out to our 1,000 yard matches and set up a kilometer away to track the bullets as we shoot them. They are using infrared technology and have commented that bullet temperatures can exceed 300 degrees C (570+ degrees F) travelling through the air. The heating of the projectiles is not just due to the heat picked up in the barrel but also the friction from the air resistance.

quote:

Originally posted by Fjold:
In regards to how much heat is on the bullet tips as they are being fired.

There is a defense contractor in the Los Angeles area who is working on a new small arms projectile tracking system (for pilots to use when landing under fire).

They come out to our 1,000 yard matches and set up a kilometer away to track the bullets as we shoot them. They are using infrared technology and have commented that bullet temperatures can exceed 300 degrees C (570+ degrees F) travelling through the air. The heating of the projectiles is not just due to the heat picked up in the barrel but also the friction from the air resistance.

The SR-71 is another data point to support your post.

Gimmick!
Have recovered enough BT & Accubond tips to know that they don't melt.

Cheers.

quote:

Originally posted by 416RigbyHunter:
Gimmick!
Have recovered enough BT & Accubond tips to know that they don't melt.

Cheers.

.

How far had the NBTs and Accubonds traveled?

there we have it! The difinitive answer from no less than the world renowned Physicist and Ballistics Engineer from OZ...

I believe Hornady's claim about plastic tips melting has credibility, although the effect on the G7 BC is small.

Specifically, if you look at Bryan Litz's BC data in his book "Ballistic Performane of Rifle Bullets", you'll consistently see a mild decrease in G7 BC from 3000 fps to 1500 fps.

This mild decrease does not occur with non-tipped or lead-tipped (all copper) bullets.

Given the manner in which Bryan measures BCs, this mild decrease in G7 BCs is entirely c/w the plastic tips of Nosler (and other) plastic-tipped bullets types melting, especially after traveling past 400 yds.

The plastic tip must be exposed to air friction for a sufficient length of time for the tip to melt.

It is always fascinating to read about the nuances shooting long range especially the technical validations of new or even established information.

But just for moment, let's consider another aspect of this development in particular. I'm not casting aspersions on Hornady but looking at this development from a different perspective.

What if the original AMAX tips were fine but Hornady was looking for a slightly higher profit margin without taking the chance of alienating too many of it's dedicated clientele by just raising prices? Say they came up with idea of coaxing some dollars out of the brand by simply applying a new tip but backed up with some quasi-scientific but fully believable 'data'? Simply set about convincing the buying public that they had noticed a slight deficiency, did their homework and then set about to correct that deficiency in order to supply the public with a better, improved product.

Voila! Instant profit margin improvement to go along with the product improvement. All they did was raise the price of the product from let's say $31.00/100 to $38.00/100. Result? Instant 23% profit on a minimum investment on existing technology but couched in favor of the shooting public with improved performance.

No harm intended just another way to look at some information.

Regards.

Data or profit notwithstanding, I've experienced excellent accuracy with the new ELD-X bullets in 6.5, 7mm and .30.

A friend just returned from an extensive plains game safari and reported excellent terminal performance on everything including blue wildebeest and zebra with the 143gr. ELD-X in a 6.5 Creedmoor. Darrell Holland's latest email report indicated similar results on NZ stags.

I look forward to giving these bullets a chance when the leaves turn.