Home Forums Hunting & Shooting Ask The Gunwriters 6.5mm 120BT's vs 7mm 120 BT's

Over the years, I've seen NBT's shoot slightly tighter groups than NAB's.

What's your experience with these two?

DF

Thanks whttail you sir are a cool kid ha! Please teach me oh yoda to do such thinks from the iPad.
Big Ed

Originally Posted by rickt300

I have just taken possession of 4 boxes of 120 gr. Ballistic Tips to run in a 6.5 Grendel. At 2500 fps I expect good expansion and penetration from them along with fine accuracy. For years I avoided using Ballistic Tips because of the bad press they got early on but when that turned around I found them great bullets. A favorite is the 150 gr. .284 diameter Ballistic Tip. This bullet will do a heck of a lot of work out of a medium 7MM rifle.

Indeed. I have loaded that in my 7x64 and shot groups down to .35 inch. One of these bullets hit a young boar running away. It entered down its left flank behind the last rib and exited out the throat. Penetrated over two feet.


I have some 100, 120 and 140gn 6.5mm Ballistic Tips but have only shot paper with my 6.5x55. All have grouped under an inch at 100m (3 shots). The 120gn Ball. Tip will be the first bullet I try in my 6.5 CM when I get it.

I don't have anything with iOS, so not much help. Easy-peasy on a PC.

Those are my findings as well, particularly with the 6.5mm 123 grain SST and the early versions of the 129 SST. In a 24" 6.5x30-30 AI, the 123 grain SST proved to be exceedingly accurate. I decided to try it when the 120 grain Noslers were hard to find. On several hogs, including a couple of bruisers, I got excellent terminal performance with a load that clocked right at 2600 fps. Then came an opportunity for a double when a 50 pound shoat stepped in front of a sow (she was on a bit of a downhill grade, and they aligned perfectly). I took the shot from about 165 yards. The shoat dropped, and the sow disappeared into the brush. I was confident she was down just inside of the brushline. But there was no blood and no other indication of a hit. I went back to check the shoat, and I quickly saw that there was NO exit. No substantial piece of bullet was recovered from this ribcage shot, and the innards looked like I dropped a frangible bullet from a 22-250 into there.

But I never judge a bullet from one incident and kept using it. Things were going well again until I experienced two more with poor performance. That -- coupled with the shoddy performance of the early versions of the 129 grain SST -- turned me away from them for good.

As for anyone who may be curious, the 6.5mm 120 grain Ballistic Tip will out-penetrate the Hornady 123 grain SST, as will most hunting BTs when run against a comparable cup-and-core projectile.

Bobby,

SST's have been toughened up considerably since their introduction--much like SOME Ballistic Tips.

A good example is one of my local friends, who handloads 162-grain SST's for his family's several 7mm rifles, mostly 7mm Remington Magnums. He killed a bull elk last fall with his 7mm RM at around 150 yards, the SST entering behind the left shoulder and breaking the right shoulder. He found it perfectly expanded under the hide on the far side, with the core firmly inside the considerable shank left on the mushroom.

Last fall I took part in a gun-writer hunt in South Texas, where close to 30 pigs and deer were taken with .308 Winchesters and factory loads with 150 SST's. The largest pigs and deer weighed close to 200 pounds, and not a single SST was recovered, even on severe bone and angling shots.

Most of today's hunting bullet manufacturers tweak their products to improve performance, both in accuracy and on game.

It is surprising that bullet companies do not advertise what they have done to improve performance. We are therefore left with beliefs that are no longer true. While grateful for Mule Deer to update us, it seems to be a marketing benefit largely ignored.

IMO, it would be helpful for companies to put out a notice of changes so we'd know. Once I got burned with early NBT's, I would never have used them again, but I learned they are now a different bullet. And I learned that here on the Fire.

Same with SST's. I think makers would benefit with a more heads up, transparent approach. But, I guess they'd have to admit the weakness of earlier versions, as if we didn't already know. Maybe their PR/marketing types discourage that. There's power in knowledge. Maybe good marketing, too.

After reading JB's comments on SST's, I'm more likely to try them again. Like NBT's, they've always been very accurate. Depending stictly on Nosler and Hornady info, I'd never again use either one, be off and running with other choices.

DF

The problem is, we still don't know if all or some of the bullets have been "toughened up". So if you want to try a particular bullet, you won't know until you stick it into an animal whether it's been improved. That's a roll of the dice that I'm reluctant to take, as long as there are other options with "known" characteristics.

You pretty much have to take it upon yourself to cross section a bullet to examine its construction or shoot it into a constant medium to compare penetration and expansion every time you buy a new batch of bullets to find out for for yourself in these days of unannounced bullet change ups..

I guess one could use older ones on targets, new ones on game.

I wonder if companies would give lot numbers on toughened bullets if asked?

DF

I'd imagine if you order from a company like Midway that has high volume, the older lots have been sold, but no doubt lot #'s would confirm. Good info on the SSTs John.

Yes, you are indeed correct, and from personal experience I know that is certainly the case for both the 6.5mm/129 and .30/150. But the 123 SST is perplexing as these were current-production bullets from 18-20 month ago. I know that from talking to Hornady, and the guy I spoke with mentioned the 123 grainer was basically designed from the ground-up for the Grendel and did not think they had been tweaked, as have others in the SST line.

Perhaps I ran into a bad batch. Perhaps it was just sheer coincidence. But after the third instance of poor performance, I moved back to the Nosler 120 BT and 130 AB.

The picture of the 123 grain SST below (recovered from the hog in the other photo) is typical of the performance I had been getting -- about as close to perfect as one could hope for. Again, I never judge a bullet by a single episode of questionable performance, but three instances took me aback somewhat.

John, if you happen to know if they've changed the 123 grainer in the past 2 years, please let me know. They shot incredibly well with N160, and an average of six 3-shot groups at 200 yards from my 24" MGM Contender barrel in 6.5x30-30 AI was barely over 0.9".

Yes I emphatically understand what you are saying about my water medium is not as good as dry news paper and it’s not as accurate of a predictor of bullet performance. But, when comparing apples to apples,both the 120 bt and the 120 SST shot into water jugs,the SST held together and x2 102 bt tested did not hold together. Now I know that’s comparing a 6.5mm vs 7mm but that’s the only variable other than the 6.5 bt is traveling 250 fps faster. That might be a factor to. I’m planning on comparing the 7mm 120 bt vs the 120 SST and again the 7mm 120 bt is traveling 3k fps vs the 120 SST traveling 2,675 fps. Take it as you will but it’s good enough for me but I understand your superior knowledge on the newspaper subject.
Thanks,
Big Ed

Its even worse if bullets makers "toughen them up" and then "soften them up"? WTH is that? There is a time and place for cup and core, stout bullets and even monos. But how stupid are the manufacturers for not telling us? That would be like changing the formulation of a powder and not re-testing it and then updating their manual.

Bobby,

You may have gotten a bad batch. I have known that to happen with more than one brand of big game bullet.

whitearrow,

As I pointed out in an earlier post, when heavy-jacket Ballistic Tips separate core and jacket it doesn't really matter, because the jackets still retain over half the original bullet weight. A LOT of hunters still think jacket-core separation is automatically a "failure," and it could be when even big game bullets had relatively thin jackets. (Though I've had two thin-jacketed big game bullets leave their core at the ENTRANCE hole on buck deer, yet the cores penetrated on into the chest and killed them.)

Yes, 250 fps in muzzle velocity can make a BIG difference in cup-and-core bullet performance, so you are NOT comparing apples to apples.

Yes, your test medium sucks, and you're assuming single examples are meaningful. Shooting at least 3 bullets into media is better, and 5 much better yet.

sorry you see things as such mule deer. Nothing at all sucks about what I’m doing and I don’t have an unlimited budget to shoot multiple bullets into my limited test medium my wonderful water filled gallon milk jugs. If they can’t get it done on 2 tries that’s all I need to form an opinion. I guess you shoot deer more than once to get different takes on it if you don’t get the desired results. I enjoy what I do with penetration/expansion bullet tests because usually my 14 yr old son is my designated shooter. So,A lot more than bullet tests going on out there.
Thanks,
Big Ed

It's not apples to apples with a 250fps difference. Hard to compare performance with that much difference in velocity.

Glad you enjoy it with your son!

My point, however, is that most people shoot bullets into "media" in order to obtain a reasonable idea of what will happen when the same bullets hit game. Your method won't do that very well. But carry on....