.308 - 8mm - .338

Started by gitano, May 15, 2009, 03:41:28 PM

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gitano

It’s no surprise to anyone that has been here at THL for very long that;
 
1) I like the .308 Win case, and
2) I like the 8mm caliber.
 
These are purely emotional preferences and my intent is not now, as it never is, to “defend” those personal preferences. That doesn’t prevent me from continuing to extol their virtues as I see them. Such will be the case in this thread. I will be comparing two other calibers to the 8mm, one I also “like” (.338) and one I don’t (.308). But the point is not to denigrate those but rather to illustrate the relative “fitness” as a hunting cartridge, of the .308 Win case with the 8mm caliber. So…
 
The three cartridges in comparison will be the “root” of it all, the .308 Win, the wildcat 8mm-08, and the newly commercialized .338 Federal.
 
When a cartridge manufacturer gets the idea to commercially introduce a new cartridge, they truly undertake a daunting task from a business perspective. There are significant investments necessary and considerable risks involved. Mitigating the risks is precisely why they pay so handsomely for gunwriters (ptooey) to write favorable reviews. Of course when a new cartridge is commercially introduced, there are literally legions that line up to pan it, thereby (they believe anyway), demonstrating their “expertness” in the manly arena of “firearms knowledge”. The truth of the matter is, there isn’t a cartridge commercially available today that isn’t at least “good” as a hunting cartridge. Modern ammunition and weaponry are excellent hunting implements. The differences between them all is little more than tempests in teapots. So, when Federal (it wasn’t just them), introduced the .338 Federal cartridge, the usual full-spectrum of hoohah resulted. Personally, I really like the cartridge because I really like the .308 Win case and the .338 caliber. For me though, I wish they would have chosen the 8mm as the caliber to put on the .308 Win. case. Of course I know why they didn’t – 8mms just don’t sell in the US. Sad, but true. All of that notwithstanding, I am going to paper-whip what “might have been”.
 
(On a side note, during all of the WSM and WSSM frenzy, the .325 WSM (the 8mm version), was among the last of them to be rolled out, and its sales flag far behind the other variations on the WSM/WSSM theme.)
 
To make sure we are comparing apples to apples as much as possible, I’ll lay out some initial and boundary conditions.
 
1) All comparisons will be from 24” barrels.
2) Max SAAMI pressure for the .308 Win and .338 Federal is listed as 60,191 PSI. The wildcat 8mm will be held to the same. However, the pressure ceiling I will use for these comparisons will be 56,565 PSI because that is the standard for the model 98 Mauser bolt action rifle – which I also ‘like’. The .308 Win case is a “short” case, and rifles other than the M-98 Mauser could handle the short case with a short action and higher max pressures. However, 56,565 is only 6% down from the SAAMI max of 60,191. In other words, the 56565 is ‘pushing’ the limit of the .308 Win case.
3) Since bullets clearly can’t be “apples-to-apples”, I’ll pick the ones I feel are most similar – mostly in ballistic coefficient, since that most determines the external and terminal performance. Note that the difference between the diameter of the .308 and the .323 is 0.015”, and that the difference between the .323 and the .338 is also 0.015”.
4) All bullets will be seated to 2/3rds of a caliber. For the .308 that’s 0.206”; for the .323 that’s 0.216”; and for the .338 that’s 0.226”.
5) Charges will be allowed to go up to 105% of case capacity.
6) Charges that burn 100% in the barrel will be used instead of those that burn less even if the one that burns less generates a higher MV IF the difference is 50 f/s or less. If the difference is greater than 50f/s, the powder generating the higher velocity will be used.
7) Only powders available in the US will be considered. Apologies to our foreign members, but the permutations are too great if I include powders from around the world. Besides, this isn’t about “best”, so comparisons using ‘similar’ powders are reasonable.
8) Trajectory tables will be standardized with a maximum range of 300 yds, and sight-in distances will be for 6” targets – maximum of 3 inches above and below the line of sight – with the sight 1.5 inches above the centerline of the bore.
 
The comparison ‘yardstick’ that I will use most, is my personal standard of;
1) Max 3400-ish ft-lbs at the muzzle for recoil mitigation,
2) Total vertical deflection over 300 yds of 12”,
3) Deliver 2000 ft-lbs out to 300 yds.
The cartridges don’t have to meet the above criteria; they will simply be discussed in the context of those criteria.
 
As I said above, this isn’t about “best”. Rather, it’s mostly “about” 1) discussing a case and caliber I happen to like, and 2) another example where performance takes a back seat to marketing reality – namely, “If you can’t sell it, it doesn’t matter how “good” it is.”
 
Finally, this is paper-whipping. It ain’t reality. As I said above, it is my heart-felt belief that every cartridge commercially available today is a satisfactory hunting cartridge in one light or another. Not one of the above three cartridges would kill any ‘deader’ than either of the other two. (Although… the one difference that probably does matter somewhat – “lethality” – is out of our reach to quantify.) Differences these paper numbers illustrate are no less “tempests in teapots” than any other comparison of three modern hunting cartridges. But it’s raining and I can't go to the range as I had planned.
These calibers are in the ‘no-man’s land’ of being neither “big bore” nor “small bore”. Therefore, I will be looking at both light-for-caliber bullets, and heavy-for-caliber bullets. I might even include some “medium” weights if they look interesting.
 
Here ya go…
 
The bullets that gave the “best” numbers were:
 
.308 – 125g Nosler Ballistic Tip
8mm – 125 Hornady Spitzer
.338 – 160g Barnes “X” ***
 
.308 – 200g Nosler Accubond
8mm – 220g Sierra BTSP
.338 – 250 Nosler Accubond
 
 
*** I used the Barnes 160 “X” in spite of the fact that I have extensive personal experience with this bullet, and I can’t get it to shoot straight AT ALL. However, it is the lightest bullet commercially offered in the US in .338, so I went ahead and used it for the light-for-caliber bullet for the .338 Federal.
 
I think I’ll ‘cut to the chase scene’ – the external ballistics/trajectory - since that is what most folks are likely interested in. If the external ballistics suggest a look at the QL “front page”, we’ll do so.
 
First, have a look at the trajectory tables for the light-for-caliber bullets:

 

 

 
Summarized:
 
Cal/bullet .. . MV f/s . . ME ft-lbs. . . . . V300 f/s . . . . . E300 ft-lb . . . . . D300 in.
.308/125 . . . . 3172 . . . . . . 2792 . . . . . . 2463 . . . . . . . 1684 . . . . . . . -2.5
8mm/125. . . . 3240 . . . . . . 2913. . . . . . 2206 . . . . . . . 1351 . . . . . . . -3.4
.338/160 . . . . 2885 . . . . . . 2957 . . . . . . 2153 . . . . . . . 1647 . . . . . . . -5.4
 
As you can see, the 8mm does a good job in comparison to its ‘relatives’ on either side.
 
Impact velocities are all over 2000 f/s, meaning that the bullets should perform as designed terminally.
 
Trajectories are all under the 12” ceiling - 5.5”, 6.4”, and 8.4”.
 
Muzzle energies are better (lower recoil) than an ’06 shooting a 180-grain bullet at 2800 f/s.
 
Terminal energies are sufficient (according to the experts) for elk in the .308 and .338, but… I’d be loathe to shoot an elk at 300 yds with anything other than the .338.
 
Were it not for the great BC (0.366) of the 125-grain .308 Ballistic Tip, the 8mm would “win” this comparison. I think that if there was a real light-for-caliber bullet in .338 – say 150 or even maybe 140 – it would do quite well in this comparison. It’s too bad US bullet-makers don’t make high-BC bullets for the 8mm, or low-weight bullets for the .338. That 125-grain .308 Ballistic Tip is a bullet I’m going to have to investigate!
 
Now let’s look at the high end of the weight range:

 
 

 
 
 

 
Summarized:
 
Cal/bullet .. . MV f/s . . ME ft-lbs. . . . . V300 f/s . . . . . E300 ft-lbs . . . . . D300 in.
.308/200 . . . . 2525 . . . . . . 2831 . . . . . . 2131 . . . . . . . 2016 . . . . . . . -7.6
8mm/220. . . . 2504 . . . . . . 3063. . . . . . 2094 . . . . . . . 2142 . . . . . . . -5.3
.338/250 . . . . 2386 . . . . . . 3160 . . . . . . 1996 . . . . . . . 2211 . . . . . . . -9.6
 
Again, the 8mm does a very good job relative to its ‘relatives’ on either side.
 
Impact velocities are at least 2000 f/s, (1996 is close enough to call 2000), meaning that the bullets should perform as designed terminally.
 
Trajectories are at or under the 12” ceiling – 10.6”, 8.3”, and 12.6”.
 
Muzzle energies are creeping up there, but well below the 3400 ft-lb ceiling, and only the .338 exceeds the ’06 180-grain at 2800 ft-lb yardstick of 3132 ft-lbs. Not one of the cartridges is “killing at both ends”.
 
These are all clearly 300-yd elk and moose cartridges/bullets.
 
So... The 8mm-08 would be far more interesting a cartridge to me than the 7mm-08 is.
 
Paul
Be nicer than necessary.

drinksgin (deceased)

#1
Paul, .338, 160, 300yd dr. ,5.4"x2=8.4"?
NRA life, TSRA life, SAF life, GOA, CCRKBA, DEF -CON

gitano

As usual Don, you keep an eye on me. Thanks! I appreciate it! The 300 yard drop should be -5.2" instead of -5.4" The total vertical deflection would be 3" high plus 5.4" low = 8.4" total.
 
Paul
Be nicer than necessary.

22hornet

Good work, as usual!
 
I use those 125gn Ballistic tips in my .308 and they are great. My load is quite mild but it works well for me.
43gns of AR2206H in a 21" barrel. My cases are Highland and they are quite abit heavier than Winchester.
 
Your energy levels in all cases are abit misleading. It doesn't take into account the larger diametre of the projectile, something that I believe does make a difference.
"Belief:" faith in something taught, as opposed to "knowledge:" which is awareness borne of experience.

gitano

I wouldn't actually call the energies "misleading", but we agree completely that diameter does make a big difference in "lethality". Unfortunately, "lethality" is very difficult to quantify.
 
I am aware of seveal "formulae" for determining "lethality", and most of them I don't waste time with. They're usually just some gunwriter's (ptooey) attempt to show how "smart" they are, or an effort to get their name in the "annals of firearms history". Most of them simply put an arbitrary number to what is already known - bigger diameter bullets generally take animals off their feet quicker. I don't need an equation to tell me that.
 
KE, while certainly not a measure of a bullet's "lethality", is in fact 'real', and does provide a measure of some component of lethality. It's just not a complete ruler. Have a look at this thread http://www.thehunterslife.com/forums/showthread.php?t=566
for my thoughts on what the real phenomenon is regarding how we might quantify 'lethality'.
 
Paul
Be nicer than necessary.

sakorick

#5
Quote Paul "Muzzle energies are better than an ’06 shooting a 180-grain bullet at 2800 f/s".


There you go again. 30-'06 180gr Nosler BT .507BC bullet 2800'/sec with a 250yd zero.


muz                          ME3133
100yards=   +3.0     E 2748
200yds         +2.4     E 2402
300              -4.0      E  2093

Now Paul, please explain that or are my numbers wrong? OBTW, the numbers for E are 100+ more with a 200 grain bullet.  Regards, Rick.
3
Talk to yourself. There are times you need expert advice.

gitano

I think you just mis-interpreted what I meant by "better", Rick.
 
I am linking muzzle energy to recoil. Therefore, "better" - at the muzzle - means less energy. Your figure of 3133 ft-lbs is exactly what I get for a ME for a 180 doing 2800 f/s. With the light-for-caliber bullets in the .308 case, the MEs are 2792, 2913, 2957 ft-lbs - all less - meaning "better" - than 3133. Since the heavy-for-caliber bullets have even lower MEs, they are "better" too.
 
There's no intent on my part to mean-mouth the '06 in this thread. I am simply using it as a yardstick almost everyone is familiar with.
 
Paul
Be nicer than necessary.

sakorick

Quote from: gitano;92931I think you just mis-interpreted what I meant by "better", Rick.
 
I am linking muzzle energy to recoil. Therefore, "better" - at the muzzle - means less energy. Your figure of 3133 ft-lbs is exactly what I get for a ME for a 180 doing 2800 f/s. With the light-for-caliber bullets in the .308 case, the MEs are 2792, 2913, 2957 ft-lbs - all less - meaning "better" - than 3133. Since the heavy-for-caliber bullets have even lower MEs, they are "better" too.
 
There's no intent on my part to mean-mouth the '06 in this thread. I am simply using it as a yardstick almost everyone is familiar with.
 
Paul
Okay Paul, I give up. I can't compete in a math game.....but my '06 can! Everyone on God's green earth compares their pet calibers, cases and performance to the '06 and after over 100 years in service of the military and sportsmen, I remain a huge '06 proponent and a skeptic at other wannabe's. On paper and in the field a classic that will not be usurped....at least not in my lifetime. I have nothing against the 308, 8MM-08 or the Hornady whatever it is. As a matter of fact, I am currently building a 308 on a Mauser action just for you, Paul. By the way, the 308 is a by-product of the M60 machine gun and the M-14 was the finest military service rifle ever made.......but I don't shoot semi autos/fully automatic rifles as a sportsman. By the way, just what's wrong with the 8mm-'06 in this comparison? :D Regards, Rick.
Talk to yourself. There are times you need expert advice.

gitano

QuoteI am currently building a 308 on a Mauser action just for you, Paul.
Does that mean you'll be giving it to me??? :bowdown: :sweetheart: :kiss:
 
QuoteBy the way, just what's wrong with the 8mm-'06 in this comparison?
Nothing "wrong", except that I was looking at the .308 case and the 8mm caliber. Personally, (now sit down, and take your heart medicine before reading the rest of this sentence),
.
.
.
I think the 8mm-06 is a "better" cartridge than the .30-06. :eek::greentongue:
 
The point of my initial post was to provide some paper-whipped numbers in light of the fact that when a new cartridge/case design is commercially introduced - like the WSM, WSSM, or .338 Federal - the .323 caliber is avoided like the plague when in fact it's a great caliber - and performance-wise, it cannot legitimately be argued that the .338 is "better". What can be legitiamately argued, in my opinion, is that the .338 caliber is a better seller in the US. And selling IS what matters in 'commerce'.
 
 
My use of the '06 as a performance yardstick has nothing to do with my 'attitude' about the .30 caliber. On the contrary, I use it because it is so widely known. Saying an unknown cartridge "kicks less than an '06" is like saying snake "tastes like chicken". Most folks haven't eaten snake, but have eaten chicken. Therefore they can get an idea about how snake might taste to them. In this example, if you can 'take' the recoil of an '06, you'll have no problem with the 8mm-08, or the .338-08 either for that matter.
 
Paul
Be nicer than necessary.

klallen

i tend to agree, it is unfortunate the 8mm class isn't better represented.  based on the aversion towards the class as a whole by the industry, i was a little suprised (happily so) to see it offered as an option in the wsm line of cartridges.  albeit, attempting to get away from the 8mm or .323 moniker as quickly as they could by calling it a .325wsm, it was/is still a nice move forward for the class.  maybe more will come.  i have no real need for an 8mm on that little -08 case, or the '06 for that matter, but certainly wouldn't be against a savage 14 american classic in .325wsm finding its way into my safe.  love to see how it would respond to the 200 gr. accubond.

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