BillBrasky

So I have been toying with the idea of starting to reload and I've been trying to figure out what kind of cartridge I want to build. I have a .308 with a 1-10" twist and an 18" barrel so it prefers the heavier loads (168-200 gr) versus lighter loads, which is fine because I want this recipe to work for deer and the occasional elk. My best groups were with M118L loads with a 175 gr SMK, but the only hunting bullets I can find in that weight range are Berger VLD's, which aren't widely available and have a checkered reputation (some people swear by them and some people swear at them).

When I look at match bullet weights it seems like the go-to bullets are either 155, 168 or 175 grains, while the majority of hunting bullets are either 150, 165/168, and 180 grains. If the match weight bullets are supposed to optimize energy retention over long distances, then why is the match load 5 grains lighter than the hunting loads? Is the amount of case capacity lost negligible when going up five grains of lead? Or is it just economics--it's cheaper to make an all purpose medium-heavy bullet that will work better for the 30-06, 300 WinMag, etc., but will still work "pretty well" for the smaller cased 308? Anyone have any thoughts on this?

BillBrasky

I understand that BC is a large part of the terminal ballistics of a load, but there is also the matter of energy transferring from the expanding powder to the bullet itself. When a bullet becomes larger and must be seated deeper, it's extra size comes at the expense of case capacity. For instance, the 175 and 180 grain SMK's have virtually identical BC's between 2800 and 1800 fps, but the heavier 180 grain bullet will need to be seated slightly deeper than a 175 grain bullet, correct? That would mean that the slightly smaller bullet with the same BC may have an edge because it would allow for more propellant which means a higher muzzle velocity and energy.

My question is whether the standard 180 grain hunting bullets are much more available because the amount of powder being lost is inconsequential regarding ME and MV, or if it's because the larger cases of the 30-06 et al., are better suited to the heavier bullet and it's cheaper to produce one bullet that works decently in all .30-cal weapons.

If it doesn't make one bit of difference between the 180 and 175 grain bullets, then I was thinking of a 180 grain Partition or Ballistic tip as being my load of choice. If there is a substantial difference between the 175's and 180's, then it may be worth it to try out those 175 grain VLD's.

goatbrother

Could be the SMK is sleeker, longer, and has longer bearing surface causing the bullet to be seated deeper in the case thus reducing capacity and the longer bearing length causes more friction and thes increases preasure enough to warrant the reduced powder charge.

Prairie Wolf

I think you are splitting hairs here. In theory, the lighter bullet should go faster, but the difference in weight in this case is so small it might get lost in the other variables. The BC's may vary slightly from the manufacturer's numbers also, and they will vary from gun to gun. Some guns spit the bullets out with a yaw angle and it takes awhile to stabilize, and they have a lower BC till that happens.

The 180 grain hunting bullet is most likely shorter because it won't have as long a nose, and maybe not a boat tail.

I would guess the weights that are available are because that is what we've always done. The 150, 165, and 180 are what has been marketed to the public from way back, and the match bullet weights were probably specified by the military.

Realistically, the only place you can have substantial differences are in BC, accuracy, and terminal performance.

The differences in velocity are not worth the effort.

The differences in BC won't come into play until you get way out there.

The differences in accuracy matter a little more, but again, not until you get way out there, as long as you are getting decent accuracy to start with.

The differences in terminal performance can be important, but if you hit them where it counts it hardly matters, as long as you get some expansion. Sierra says don't use SMK's for hunting but some people do anyway. We have gotten pretty carried away with premium bullets these days but a deer won't notice the difference. Premium bullets just aren't necessary unless you are getting way out there, or shoot a magnum that blows up plain jane's.

BillBrasky

Thanks for the detailed reply wolf. I was wondering if I was making too big of a deal out of the weight differences, but it never hurts to ask.

With regard to premium vs cheap soft-point bullets...

The main reason I was curious about energy and velocity was not so much a concern about deer, where a .308 is more than enough, but for elk. Right now the 180 grain winchester power points work just fine on deer out to about 300 yards, but I'm guessing that will not be the case if I come up on a big bull at the same distance. A lot of what I have read about the accubonds and Barnes bullets says they're great on penetration but they need to be at a decent velocity if they're going to expand. On the other hand, softer nosed bullets may expand too rapidly or may not stay together when hitting a bone so I would be reluctant to use the power points in that situation.

Another note about my gun is that the action is kind of weird. It's not quite a short action, it's not quite a long action... it's somewhere in between. That being said, the magazine holds 200 grain bullets just fine. Granted they're at a lower velocity than the 180's, and they won't shoot nearly as flat, but would this weight in a soft point or powerpoint still work on bigger, thick-skinned game?

dig4gold

168 grain Noisler Balistic tip does the job on elk very nicely. I shoot .308. Wanna see the pictures? It also has a very high BC of .490!168 seems to be the weight of choice for a lot of bench shooters. There is load data on the Nosler site also.

homers brother

There was a time, not so long ago, when a .308 and 150-grain bullets were perfectly adequate for deer. In the years that have ensued, deer have morphed genetically to the point that they are now nearly impervious to anything under a 180 grain bullet launched out of a case with the word "magnum" stamped upon it.

As a kid in SW Colorado in the late '70s, we joked that anything bigger than a .30-06 at Gardenswartz, the Outdoorsman, or Kroeger's was stocked for the elk hunters from Texas who'd show up at La Plata County Airport with a big Stetson on their head and nothing else but a wad of Benjamins in their pockets. Old timers still using their .30-30s laughed at us.

The sad truth is this - using a .308, 150s are perfectly adequate on deer. 180s should be fine out of your 1:10 barrel (my 20" 1:10 likes heavier bullets as well) for elk.

Read less, hunt more.

HatchieLuvr

"Split the difference" and put a 165 TTSX Barnes in your old '06 and you're set for anything with hair this side of a brown bear (and in a pinch that would work as well, but were I goin especially for the big bears I'd want alot more frontal area and weight than any of the popular deer calibers!)

If your 308 just wont shoot 165/168s as well as 180s then I'd stick the 180 TTSX in it and never look back. Inside of 400yds you nor the animals are going to tell a tremendous difference between the 165 or the 180.

To answer your original question, yes you're splittin hairs 175 vs 180... No sense in trying to rework a wheel that's been in existence for over a century!