Home Forums Hunting & Shooting Ask The Gunwriters Bullet Manufacturers- Why Can't they do this????

I was just looking at the new Hornady GMX bullet. At first it looked promising, but then I saw their performance pictures for the 30 cal. 150 gr. and realized they have done it again; designed one bullet for four different rounds, 308 WIN, 30-06, 300 WIN MAG and 300 RCM. They show a near perfect and complete mushroom at 3400 fps, a lesser mushroom at 2700 fps, and almost none at 2000 fps. These might be great out of the magnums, but what about a 308 or 30-06 which have muzzle velocities closer to 2800 fps and are in the 2600 to 2650 zone at 100 yds.? The performance of these bullets never reaches it's full potential due to the lower velocity, and by the time it reaches 250 or 300 yds, it's almost useless.

Why can't they manufacture bullets that are more in tune with the real world velocity of the ammo they will be used in? This same bullet designed for a starting velocity of 2800 fps would be perfect in the standard 30 cal's. I know it would cost them more, but I'll bet they would make it up in increased sales.

End of rant!

You don't need these kinds of bullets in a 308 or 30-06.

They do produce such bullets. They're standard cup'n'core bullets, like the Hornady Interlock. Thank goodness they are in fact cheaper.

The necessity driving the innovation you speak of is magnumitis, and an obsession with penetration. If you don't suffer with either of those maladies, then save your money and buy those tired, out of style old cup'n'core bullets. The deer will in fact know the difference, but they won't have anything to say 'bout it at all.

InterBond is for the .308's and '06's. GMX is for Magnums.

you do if you want to hunt in certain parts of california

Exactly. And other parts of the country entirely too I suspect. Nosler, Hornady et al are getting ahead of the game so they (and we) don't get caught without a bullet that is, say, Minnesota approved. Me I'm glad they are doing so, I doubt Barnes could keep up with the demand if another state banned lead bullets.

Likely Hornady will bring out a .30 cal 130 grain GMX in a year or two and it will work just fine in our .308s and '06s.

That's my take on it anyway.

As a rough rule of thumb, Sierra and Speer cup and core bullets need to impact 2100 FPS or more to open reliably. Good old Hornady spire points open at 1700-1800 FPS. All three start to penetrate less above 2800 FPS.

Most people are surprised to learn that if you graph penetration on the vertical axis and impact speed on the horizontal axis, the line slopes down to the right. More impact speed yields less penetration.

Is that also true for monolithic bullets that loose petals and therefore have a smaller frontal diameter of the expanded bullet?

Yes, the faster the bullet impacts the larger the wound diameter and less penetration. A test a few years ago shooting Barnes 180 grain TSX in a 30-06 and a 300 RUM ballistic geletin blocks set at 100 yards with a chrono in front and rear to record the entrance and exit velocities. The bullet fired from the 30-06 exited with over a 100 FPS more velocity than did the bullet fired from the 300 RUM. The faster a projectile hits the harder the material pushes back and the faster the bullet slows. The same as in air

That's a little more difficult to say for sure.

The best data I have is that the Barnes X penetrates deeper than other bullets. I would say it's a fair guess that is because they tend to make a slightly smaller diameter wound channel.

Barnes X penetration depth is pretty constant from 1900 FPS impact to 2700 FPS, 20". The penetration drops down by 2-3" at 2800 and 2900 FPS. It then goes back up at 3000 and 3100 FPS.

It's possible that at 2800-2900 FPS the bullet is opening too much, too fast, and that at the higher speeds the bullet sheds its petals and penetrates more. It's hard to say.

As has been stated, the surprising result for copper jacketed bullets is that at too much speed, the bullet opens more and faster, resulting in a shorter wound channel. I'm not surprised at all with the comparison of the 30-06 and 300 RUM.

I haven't read Mule Deer's article on 2700 FPS being the ideal muzzle velocity, but the notion is clearly right for standard bullets. If your MV is above 2800, then it's a good idea to switch to a premium bullet. Below that, you probably won't notice the difference. Shooting a critter at fairly close range with a standard bullet at 3,000 FPS is an invitation to a bullet failure.

Woodleigh bullets are velocity disignated....

However, I don't see this as a problem. I have not had any bullet problems with todays premuim bullets in any weight or make or model at any velocity, they all work at up to 400 yards anyway...

The bullet companies have come to the point that they mostly all work on game of any size and at any decent range..I would not hesitate to use a Nosler 220 gr. 30-06 on any size animal, and have used the 150 gr. Noslers on all the plainsgame including 2000 lb. Eland with success, they preformed to perfection. Nor would I even be the least concerned with any weight bonded core bullet on any animal. I also use the same "premium" bullets in my 308 that I use in my 30-06 and 300 H&H and I have seen no differnce on game at the ranges I shoot them at. I have used the 180,165 and 200 gr. Nosler in all three calibers and some of the bonded core bullets...

If you shoot std. cup and core bullets then you should be more conscious of bullet weight and velocity.

This was not the case 40 years ago where failure was wasn't too uncommon with about any bullet except perhaps the old RN Corelokts. Failure being a bullet that didn't perform properly, even though it usually killed the animal, but keep in mind that bullet failure is a pretty good recipe for not killing an animal. If I have a bullet failure in a dead animal, I probably won't give that bullet too many more tries.

I think the bullet companies have done an outstanding job if you keep up with the technowledgy.

I have little use for cup and core bullets these days, the cost of a bullet is my least concern, the cost of fuel to get to the camp is....

previous discussion, with graph

The guy who did the research was Gary Scuichetti.

In this post I was arguing with denton's proposition that penetration decreases with speed.

I eventually decided to delete this post and to open a new topic.


PS - I would appreciate if you could go to the topic Penetration versus speed http://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/3453890#Post3453890

And give me your comments and counter arguments.

Penetration decreases with speed because of the larger expansion of the bullet as a general rule. In the case of a Tug, Tig,Light for caliber Noslers, that blow off the front portion penetrate more than convention soft nose bullets. Basic bullet 101.

I value your experience and advice, therefore I would appreciate if you could follow the link I gave above http://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/3453890#Post3453890 and comment/criticize the position I have taken on 3 types of bullets and 3 cases of penetration versus speed

Wonder how we reconcile this with those using Bergers(?); bullet "failure" after 3" of penetration seems to be a desireable characteristic in their view.I understand how the concept supposedly works, but have a hard time seeing it as "desireable" under all hunting conditions OTOH.

Maybe when it comes to killing animals all these subtle nuances of bullet performance aren't as important as we think they are.

cra....if vitals get destroyed,maybe so.....but no doubt we got better bullets now than we ever did....

I agree Bob, we're in hog heaven with regard to good bullets. I just think that we really tend to overthink the whole thing sometimes. I have to wonder how often a really good bullet saves the day when a poor shot is made, and how often a really good bullet is necessary if a shot is made right. Then, of course, we get into the issue of what kind of shot a person is willing to take. For me, working toward killing an animal with a single, certain, well-executed shot is another element of challenge in this hunting thing. Others may cite the "last hour of a high dollar hunt" scenario as justification for taking iffy shots. I have no argument with that either. To each his own. All that said, I probably agonize over terminal performance as much as anyone and probably with less justification. It's the same with accuracy. Most of my deer are shot at less than 200 yards, many under 50, with only one or two in a typical year out around 300 to 400. Despite that I don't feel good going into deer season without at least four or five rifles consistently shooting sub minute. At least I've gotten to where I'm happy with my woods guns if they're keeping everything under a minute and a half.

We complain about ammo prices now if they started doing specailized bullets for each cartridge the prices would go through the roof agian!!! Reloading is the answer.