Home Forums Hunting & Shooting Ask The Gunwriters Help Re: Ballistic Tip 6.5 & 7

I can’t remember. Which Ballistic Tip 120 grain bullet has a very heavy jacket, the 6.5 or the 7? If I remember the bullet was made with a jacket that is about half of the bullet weight. Was done to please silhouette shooters. Thanks.

The .284 be the one...

Yep, the 284 caliber.

I dunno about the 120 ballistic tip, but Ive been very impresse with the 7mm 140 grain flavor.

The 7mm 140’s work well on pigs and deer. If I remember right, the 120’s have a thicker jacket for silhouette shooting???

120 nbt was the one Gale Root redesigned at the request of 7mm handgun shooters to have a thicker jacket slowing expansion and providing longer dwell time on steel targets. Mb

Thank you all for the help.

Magnum Bob
Please elaborate on “dwell time”. I am not disagreeing; just don’t know.

dwell time
nounTECHNICAL

time spent in the same position, area, stage of a process, etc.
"dwell time at US airports has reached a new high—almost 70 minutes"

Time from initial contact (with the steel silhouette) to complete disintegration of the projectile.

Dwell time, interesting.
Long ago I built a gong on a wood platform on which I could practice shooting. I was shooting a 270w usually with 130 or 150 grain bullets. I tried some 170 Speer bullets and one of those would tear the gong from the platform whereas the lighter bullets didn’t disturb it in the least.

The 6.5 120 Ballistic Tip is pretty stout as well. Shot a pronghorn a few years ago in the right shoulder as it stood quartering toward me at around 250 yards, and found it under the hide of the left ham. Muzzle velocity was around 3100 fps.

The 6.5 has been really good for us at the deer camp, but we haven't yet diagonalized one.

Rin B , mathman hit it ,the problem was the bullets were coming apart so fast that the targets didn't fall over before the energy was gone. So jackets were thickened to slow
Expansion. That took care of the problem. Mb

I'll pick a technical nit. I'd say it was about better transfer of momentum.

No question the 7mm 120 is a stout little bullet and a great performer on game. I am just not sure if any of this carries over to the 6.5 mm iterations.

I think the 6.5 mm BT was designed to handle .264 Winchester velocities so may have resulted in the same stouter bullet as the silhouette bullets were designed for, but don't know.

Of these two no complaints on game for me.

mathman: why would momentum be more apropos than energy? Both are functions of mass and velocity. Not trying to pick a fight (I agree it's a nit). Just curious as to your rationale. Thanks

It has to do with the mechanics of the collision. The collision here is not elastic, elastic being the type of collision in which kinetic energy is conserved.

But do it Kill?

It do.

I understand that it is inelastic. The energy is used in tissue disruption. No bullet has enough momentum to knock an animal over. Seems to me that the energy would be of more significance than the momentum. But that's just a guess on my part.