Saturday, March 22, 2014

The .30-06 Project....Eating Ballistic Celery, Pt. 3

The Heavyweight...180 grains.
In the early part of the 20th Century, when the '06 was first getting it's legs under it, bullets looked much the same as they do today on the exterior- except they were far different internally. The jackets tended towards thin and the bonding process common today in which the bullet jacket and core are molecularly bonded together was still several decades off. Those early bullets when pushed to previously unheard of velocities by smokeless powder quite frequently just came apart on impact. Ballistic engineers back then handled that in a couple of ways. The first was to simply make the bullet "full patch" or as we know it- "full metal jacket" in which the bullet is designed for zero expansion by virtue of a continuous gilding metal jacket. Such ammunition was frequently used in sporting applications back then but serious wounding and slow, sloppy kills were the result. In modern times this type of ammunition is frequently prohibited by law for hunting and common decency prevents us from using it in the few places where it is legal outside of very special applications in which it is appropriate.

The other way they helped that bullet survive the impact velocity is of more interest to us. They simply made it heavier. Where the 150gr could hit 2950 fps and often ruptured on close shots, engineers made the bullet 180grs which slowed it down to 2650 or 2700 fps or so. The result is one of the most splendidly boring ballistic combinations ever devised by man. The bullet would survive an almost point blank hit and if it did rupture the fragments were large enough to be effective on their own. Penetration was greatly increased and hunters soon learned that two holes are better than one when it comes to letting hot blood out and cold air in. In fact, for a guy switching over from the .30WCF or even one of the big black powder rounds the amount of penetration was staggering from the these heavy for caliber bullets at moderate speeds. This result was not only great on big bodied deer but on elk, moose, name it. The 180gr@2700fps was THE cartridge that made the '06's reputation as a game cartridge. When combined with a rifle scope the American hunter was deadly to previously unheard of distances on larger game than ever before and the cartridge became a worldwide success and today counts for an enormous number of game animals.

In my own experience I've used it and it works. In my test rifle the 180gr. Corelokt produced groups of 2" with regularity- good, but not stellar, although one would have to come up with a pretty bizarre scenario where that wouldn't suffice as a hunting rifle to typical ranges. Performance on game was perfected decades ago and most .30 caliber 180gr projectiles are made to function at '06 speeds to perfection and most deliver the goods. As far as gun writing goes this whole bit makes me want to yawn in the worst way. Effective, cheap and plentiful is how I'd describe the 180gr '06 cartridge.

I do find it interesting that people insist on using the newer, tougher projectiles in the 180gr '06. Really tough bullets like the TSX, Bear Claw and Etip- those bullets are made for magnum speeds not the plodding velocity the '06 generates. Plain Jane cup and core bullets for the '06 have been around for a century and were perfected a generation or two ago. There is simply no replacing the sheer amount of R&D and real world experience that has went into .30-06 ammo...regardless of what the marketing message might tell you.

And speaking of marketing...

The Middleweight ...165 grains.
A fairly new product, the .30-06 (and .308) 165 gr bullet was touted as being the ultimate compromise in velocity and bullet weight. Let's be honest here- there isn't enough trajectory and velocity difference to make any of these more appealing than the other. The difference between the 150, 160, and 180gr over 300 yards isn't more than a couple of inches and no one can typically hold that in the field anyway. Bullet performance is likewise uniform since we figured out how to taper and bond bullet jackets long before the 165gr load saw the light of day. It is there though and has gained acceptance in the marketplace although I think the 165gr weight is best served in the .308 Winchester since it's short on case capacity to shoot the 180gr to really useful velocities. There is no reason to overlook it in the '06 if you have a rifle that likes it though, but it really doesn't serve much of a technical purpose. It shoots almost as fast as the 150, it kicks a little less than the 180... but the only real difference is on the ballistic table and you can't kill anything with one of those.

My rifle shot it pretty much the same as the 150 and 180gr. and while there is nothing really wrong with it; you sure don't gain much range over a 180 and you sure don't get much more bullet than the 150gr. It may be my old age showing, but I just can't think of a real advantage for it. It is, for all practical purposes, the answer to a question no one asked.

In reality, outside of my traditionalistic prejudices, the '06 shooter will be well served shooting either 150, 165 or 180 grain bullets of good quality for almost anything that walks in N.America and most other places. If I had moose or elk on the menu (or hunted in serious bear country) I'd lean toward the 180 and if I primarily hunted eastern White-tailed deer or antelope I'd lean to the 150 but there really are no wrong answers if the hunter is a good shot and gets to practical range. Shot placement and bullet construction trumps everything else and the '06 has a lot of offer there.


Phillip said...

More good stuff. As I mentioned before, the 180gr is my go-to for the -06. That's mostly because I find it good for anything I'll hunt with this rifle, from elk and hogs to deer and exotics... but even moreso because I don't like to re-zero my rifle for different loads. With my Savage 110 from the bench, I get MOA performance from the 180gr ETips, Accubonds, and Barnes TSX. But of course, every rifle is different.

I also use the ETip, in part because it was required by law where I hunted in CA (and hope to hunt again), but also because I do like the idea of using a lead free projectile.

As far as the ETip and Barnes TSX being designed for high velocities, I'd challenge that a bit. The ETip does seem to handle 3000+fps reasonably well, but it performs admirably at the velocity I get from Winchester's factory loads as well (advertised 2750fps).

The TSX, in my experience, has some problems when it gets up past 2900fps, as the petals tend to shear and you end up with a solid blank (think FMJ) passing through the animal. It still kills, but there is often a challenging tracking job required for recovery. I guess this is addressed somewhat in the Tipped TSX, but my experience with the tipped bullet has been limited to a couple of whitetails inside of 100 yards with the -06. They are accurate and deadly, but the velocity from the Savage was nowhere near 3000.

hodgeman said...

I have to wonder if the comparative impact ranges might have something to do with it. I've seen several of the mono metal bullets recovered with impact speeds of 2000-2400fps that simply didn't expand at all. One sample could have been wiped off and shot again!

I've also heard of petals sheering off on closer range shots at high speeds but haven't seen it personally.

I like the idea of a lead free bullet but my favorite rifle shoots Accubonds so well I don't tend to mess around much... .5 to .75 MOA with a very good hunting bullet is just too good to change.

Phillip said...

I hear ya about the low velocity shots, and I know for a fact it's been the nemesis of many of my lead-free shooting friends. It's particularly apparent with muzzleloaders and shotguns, and has been the source of a lot of belly-aching... rightfully so, since these guys are required by law to use non-lead ammo. However, I also think a lot of guys are stretching the limits of these slow-moving slugs when it comes to shooting distance... and that's always going to be a strike against performance, even with lead. Smokepoles and smoothbores simply weren't intended to be 200 yard guns, and even though technology makes it "possible", it doesn't make it advisable. It's just asking too much from your ammo.

I've witnessed the petal shearing at least twice (and a couple of times where I'm not sure what happened), and I've heard about it more than I care to say. I don't hear about it with the ETips or the Hornady GMX (which was designed specifically to avoid petal shearing at high velocity).

I (and my rifles) do like those Accubonds, by the way. I've shot a lot of critters in TX with them, out to 285 (which about as far as I'll ever shoot game) and they did the trick every single time.