Nosler light for caliber bullet wall thickness

[longwinters]

Question.

I understand that the 7mm 120 Ballistic Tips have a heavy wall for their size. Is this only true for the 120's or are there others, in different calibers, that I don't know about?

Long

 

[1Shot]

I know most 30 cal 125 gr bullets are light constructed varmint bullets but the 125 gr Nosler ballistic tip is not. It is a great white tail deer bullet in the 2200 to 3100 fps muzzle velocity range.

 

[JD338]

long,

The 7mm 120 gr BT jacket is actually the 140 gr jacket cut back to conform to the 120 gr bullet weight. This makes the jacket thicker on the 120 gr bullet, thus making for a very robust bullet.
The 7mm 120 gr BT is the only bullet in the Nosler BT line that has a thicker than normal jacket. All the other offerings have their own specific jacket.

JD338

 

[PPosey]

And thats why that little 120,,7mm is such a great deer bullet in the 7mm-08

 

[FOTIS]

And thats why that little 120,,7mm is such a great deer bullet in the 7mm-08

Yup it works great! This one is from a buck at 3000 fps impact velocity.

4 shots at 200 yards with the 7mm-08
1.1"

 

[PPosey]

I've never recovered one in that good of a condition, most had lost most of the lead,,,,,, had alot of pass throughs though

 

[Anonymous]

Years ago, about 1997 I'll guess. I was working with a .338 Lapua. The tech's at Nosler told me that the jacket of the 200 grain Ballistic Tip weighed just over half of the total bullet weight. If memory serves it was something on the order of 107 gr. As I understand, this bullet is not available today, so all that being said, I guess this might not help you much...... Added to this, I did shoot a couple of antelope does with the bullet out of a .338WM and felt like they performed well. My best guess is that any of the larger calibers will have a substantial jacket.

 

[TN deer hunter]

Here is a picture of the 140gr BT and the 120gr BT sectioned.

[/img]

 

[Guest]

All I can say is, WOW! That little 120gr is one stoutly constructed BT. It's noticeably thicker all the way up the jacket once you get past the base area.

 

[JD338]

TN deer hunter

Thanks for posting that picture.
A picture is worth a thousand words!
Now I am even more impressed with the 7mm 120 gr BT.

JD338

 

[TN deer hunter]

Here is a 80# doe my nephew shot through both shoulders @ 30yds with my .280 using the 120gr BT under a heavy dose of RL19. The little 120gr BT held up pretty good, nice exit hole and great 25yd blood trail.
:grin:

[/img]

 

[Savage99]

long,

The 7mm 120 gr BT jacket is actually the 140 gr jacket cut back to conform to the 120 gr bullet weight. This makes the jacket thicker on the 120 gr bullet, thus making for a very robust bullet.
The 7mm 120 gr BT is the only bullet in the Nosler BT line that has a thicker than normal jacket. All the other offerings have their own specific jacket.

JD338

Are you sure that the 120 gr BT's jacket is thicker than the 140 gr BT's at the same point? Don't you really mean that the 120's shorter jacket is a little thicker at its ogive than the 140's at its ogive?

Another thing is that a 140 gr would be going slower and in theory penetrate deeper than the 120.

 

[JD338]

long,

The 7mm 120 gr BT jacket is actually the 140 gr jacket cut back to conform to the 120 gr bullet weight. This makes the jacket thicker on the 120 gr bullet, thus making for a very robust bullet.
The 7mm 120 gr BT is the only bullet in the Nosler BT line that has a thicker than normal jacket. All the other offerings have their own specific jacket.

JD338

Are you sure that the 120 gr BT's jacket is thicker than the 140 gr BT's at the same point? Don't you really mean that the 120's shorter jacket is a little thicker at its ogive than the 140's at its ogive?

I have been told by Nosler that they use the 7mm 140 gr BT jacket and cut it down to make the 7mm 120 gr BT. You are correct that this would give a thicker jacket at the ogive as well as the nose of the 7mm 120 gr BT. However, looking at the photo above could lead one to rethink this as the jacket of the 7mm 120 gr BT appears to be thicker than the 140 gr BT.

Another thing is that a 140 gr would be going slower and in theory penetrate deeper than the 120.

True but to a point. The longer jacket can create more drag and reduce penetration.

JD338

 

[Savage99]

JD338,

Either the jackets are the same thickness, the same temper and alloy and the cores are the same material or not? What is it?

I see the 120 gr BT as just an internet fashion. It operates above the optimum speed for best performance from a cup and core bullet.

 

[JD338]

JD338,

Either the jackets are the same thickness, the same temper and alloy and the cores are the same material or not? What is it?

I have been told by Nosler that they use the 7mm 140 gr BT jacket and cut it down to make the 7mm 120 gr BT. They don't alter the manufacturing process or use different Pb alloys.

I see the 120 gr BT as just an internet fashion. It operates above the optimum speed for best performance from a cup and core bullet.

Because it has a thicker jacket.

JD338

 

[Guest]

JD338,

Either the jackets are the same thickness, the same temper and alloy and the cores are the same material or not? What is it?

I see the 120 gr BT as just an internet fashion. It operates above the optimum speed for best performance from a cup and core bullet.

According to Nosler, the 120 is the 140, only cut down (from the tip) to be a 120gr instead of a 140gr. What this means is that the jacket is thicker in portions of the bullet than at comparable points along the 140gr bullet jacket. It also means something that hasn't been discussed yet. It means that the jacket comprises a greater percentage of the weight of the bullet, meaning the lead comprises a lesser percentage. In light of that, and due to the alloys being the same, the 120gr contains a higher percentage of gilding metal and a lower percentage of lead, which in effect means that the jacket is thicker than that of a 140gr bullet, since we are making an indirect comparison due to the discrepancy of bullet weight and overall length.

Now, as to the 'internet fashion' idea and the 'optimum speed for...a cup and core bullet' I'll refer you to the information found in my loading manuals. While Nosler generally recommends the Ballistic Tip bullets for deer and other thin-skinned game, at impact velocities under 3000fps, the 180gr .323" Ballistic Tip I'm shooting through my 8x57 is rated for elk, according to Nosler. It is the last remaining BT rated as such, now that everything above 8mm has been replaced by the AccuBond, but all these 8mm and up BT's were rated for elk - meaning they were suitable for it at 3000fps impact velocity (which I'm clearly not getting from my 8x57). And yet they are traditional cup-and-core bullets. Additionally, Speer rates their Hot-Cor bullets (which are traditional cup-and-core) for velocities well within the range that a 120gr .284cal bullet might be pushed along by something like a 7mmRemMag or 7mmWby, both of which exceed the Nosler recommended impact velocity for a good distance out past the muzzle. Further, Hornady offers suitable muzzle velocity ranges for .284cal bullets in the same 120gr weight range and deemed appropriate for medium game such as deer in the 2600-3600fps range, demonstrating their faith in the bullets' abilities to hold up under such conditions, despite being traditional cup and core bullets.

Don't misunderstand me - I wouldn't dream of launching a 120gr BT at an elk from a 7mmSTW, as it's just not appropriate. But launching one at a white-tail from a 280Rem or 7mmRemMag (with a muzzle velocity in the range of 3200-3400fps possible) would not be inappropriate if the ranges and size of the deer involved were known to be within the design limits of this bullet. To say cup-and-core bullets are not capable of operating [properly] at the speeds attainable is a blanket statement that bears little basis in fact. Would I choose something else with stouter construction than the 120gr BT? Probably. But would I be well gunned with the 120BT? Also, probably.

 

[Savage99]

You said its jacket was the same thickness and so did Nosler?

To me this 120 BT aura is just a long line of unclear inferences. No facts.

Measure the actual thicknesses on each bullet along with each jackets alloy, temper and the lead cores as well.

 

[JD338]

You said its jacket was the same thickness and so did Nosler?

To me this 120 BT aura is just a long line of unclear inferences. No facts.

Measure the actual thicknesses on each bullet along with each jackets alloy, temper and the lead cores as well.

If you give the 7mm 120 gr BT a try, you just might surprise yourself. :wink:

JD338

 

[TN deer hunter]

Steve Timm is very fond of the little 120gr BT in fact had this to say about using it;

"Heck, I don't know. I've killed two six-point bull elk, a slew of Montana mulies, a few 140/150-ish whitetails and a bunch of prairie goats with the 120 Ballistic in the 7-08 Ackley.

I've also blasted a middling moose and a bunch of other stuff with the 120 Ballistic in the .280 Ackley.

My opinion is: Yup, the 120 Ballistic will do just fine. I've never had to shoot any critter twice with it and the penetration has always been waaaay more than adequate.

One of the elk was shot straight through the center of both shoulders at about 375 yards. The bullet penetrated to the far hide and was a lovely big ball (deadliest mushroom in the woods). Both shoulders broken, but very little meat ruined. The shoulders were "rattley," if you know what I mean.

The second bull was about as far. I was above the bull and he was looking up the hill straight away. I held the crosshair in the center of the neck, using the straight spine-line, and dropped the bullet precisely between the shoulder blades. The bullet broke the spine, he was most sincerely dead, and the bullet penetrated to just under the chest hide.

I found both of those bullets.

I've shot good-sized Montana mules with it. Two that I shot in the chest had the bullet exit the azz (one was right below the bunghole, which was very cool )

The only two 120s I've recovered were on the two bull elk. Every other one; moose, deer and antelope have exited.

If I were going deer or antelope hunting tomorrow, I would load 120Ballistics in either my 7SGLC or my .280 Ackley. The 120s are tougher than 140s, they shoot flatter, they recoil less and they just plain kill $hit.



Steve"

After reading several of Steve's articles and seeing some of the animals he has taken with his .280AI and the 120gr BT I had to try it in my .280. So far this bullet has really impressed me and I quit using BT's a few years ago after a few bad experiences but I believe the 120gr BT is different and a great bullet for the .280. I think Steve has a little more knowledge and experience than most so why would I not give them a try. :grin:

 

[Guest]

You said its jacket was the same thickness and so did Nosler?

To me this 120 BT aura is just a long line of unclear inferences. No facts.

Measure the actual thicknesses on each bullet along with each jackets alloy, temper and the lead cores as well.

Ok. I'll say this as clearly as I know how:

1. I called Nosler.
2. They said the 120gr BT is the same bullet jacket as the 140gr BT, only cut down (from the open front, obviously) to be short enough to then end up 120gr when fitted to the core. They also stated that the jacket is the same alloy as the 140gr, and the lead core is the same alloy as the 140gr.
3. I deduced from the information they provided that the jacket would then be thicker at the tip than the 140gr BT, based on the taper of the jacket from base to tip.
4. I further deduced that if the jacket is thicker at the tip, then the jacket makes up a greater percentage of the bullet weight than the core.
5. That lead me to the conclusion that the lead core was a smaller percentage of the bullet's weight.
6. Bearing in mind that the alloys are the same - within manufacturing tolerances, of course - the 120gr BT has a greater percentage of it's weight in the jacket than the 140gr BT. Additionally, this indicates that the jacket wall of the 120gr BT is proportionally thicker than the jacket of the 140gr BT, based on the size of the core versus the size of the jacket. The key term here is proportionally thicker.

If this is still a mystery to you, feel free to continue to shoot whatever you like, and leave the 120gr BT's for the rest of us to play around with. My son will be expecting a big box of them for his first 7mm rifle in the very near future.