7mm08 6.5 creedmoor or 308

[Trogon]

So your preference misses 17% more, has 300fps less impact speed, recoils nearly double, and creates tiny wound channels...

Fair enough. Im getting 2100 fps MV, which is a big different in the performance for barnes, so I'd argue there. But its a fun exercise to challenge the science behind what we believe and I'll participate in that.

 

[Formidilosus]

Not familiar with AB desktop version there. Is the hit probably figured with a combo of MV variation and an amount of potential error in wind call? How much wind error does this simulation figure.

I ask mainly because I feel (although I don’t have a full dope record to prove it) like my hit probably on a 12” target at 600 with my 16” .308 is much higher than 50% from actual rounds down range. And my 24” 6.5 even more so.


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The Weapon Employment Zone (WEZ) calculator, is a 6DOF calc that uses the inputs required to see the error when specified conditions are randomized for 1,000 simulated shots.
Provided that you input good data and not cherry picked BS, it gives VERY accurate results. We miss most often due to the biggest error in any given shot. With modern rangefinders, weather meters, chronographs, ballistic programs, and precise and correct ES of groups; the biggest variable and hence error is wind. I set the calcs above to a 4mph wind. A +/- 4 MPH wind caller is an average aficionado (recent school trained sniper) with cross canyon shots, or shots with broken ground between them and the target.

As for your hit percentage, in easy conditions hit rates will be much higher. A flat range, with relatively consistent and easy to read winds is not the same as shooting in the mountains. The same exact wind caller/shooter from above with with a +/- 4mph wind call, jumps up to a 97% hit rate in easy conditions of +/- 1MPH wind uncertainty.

Not knowing your specific 16” 308 load, I’ll use mine: 175gr SMK, 2,480fps MV, 600y impact speed of 1,514fps at SAC, 31% first round hit under moderate to difficult mountains conditions-


The same under easy conditions (+/- 1mph wind), 86% hit rate-



A 16” barreled 308 has virtually the same hit rate as a 24” barreled 300WSM with 165gr TSX’s....

 

[Formidilosus]

Fair enough. Im getting 2100 fps MV, which is a big different in the performance for barnes, so I'd argue there. But its a fun exercise to challenge the science behind what we believe and I'll participate in that.

What environmentals are you using to get 2,100fps impact speed at 600y (I’m assuming you meant impact and not muzzle velocity)?

2,100fps doesn’t help as much as most think with non fragmenting monos. You’re looking at caliber to .40cal size expansion, with minimal to no secondary permanent wounding due the temporary stretch cavity, because there isn’t fragmentation. Most wouldn’t be pleased if they saw what a TSX looks like after 6-8” of penetration.

 

[Trogon]

What environmentals are you using to get 2,100fps impact speed at 600y (I’m assuming you meant impact and not muzzle velocity)?

2,100fps doesn’t help as much as most think with non fragmenting monos. You’re looking at caliber to .40cal size expansion, with minimal to no secondary permanent wounding due the temporary stretch cavity, because there isn’t fragmentation. Most wouldn’t be pleased if they saw what a TSX looks like after 6-8” of penetration.

I threw in 168 barnes, since AE had that BC loaded up.

 

[Formidilosus]

I threw in 168 barnes, since AE had that BC loaded up.

There’s quite a difference between the 165gr TSX and the 168gr TTSX in BC.

The pressure you used is corrected, had to use 62° and 25.15inHg which gives a density altitude of 6,007ft. That’s what it took to match the impact speed at 600y with the 168gr TTSX that you showed.

Using you bullet- 165gr TSX, and those conditions, gives a impact speed of 1,952fps and a first round hit rate of 41%. Under the same conditions, the 143gr ELD-X at 2,868fps MV has a 60% hit rate with 2,158fps impact velocity at 600 yards.

 

[jerodmartinez]

The 7mm08 and the 6.5 creedmoor will keep a 140 class projectile up around 1800fps @ 600. They will start that same projectile at a modest enough velocity that it will still work well at 30 yards. So 600 yards really is the operating window of those for those two in true mtn rifle configuration. 308 won’t keep a 160 class at 1800fps at 600 with 20” barrel so 600 is a little far for it.

1800fps isnt arbitrary, it’s a common minimum operating velocity for big game bullets. Slower than this and they won’t open up right.

Anyway, 7mm08 is my go to, and here’s a few I can find without having to look bery far through my camera roll. @collierrifles.. Want to talk about about a boring rifle? This one is the only part of my hunt that I don’t ever think about.

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Might be a dumb question, but what is the black ring on the barrel that looks like electrical tape? Seen it on several barrels.
Thanks

 

[CBreeze]

Electrical tape so when I fall I don’t plug the barrel with snow or dirt and hopefully not **** up my crown. That ring is another 4-6” of tape so I can replace it after i shoot and start to pack out. The usual follow ups to your first question are about pressure in the barrel and harmonica of the barrel. The muzzle tape doesn’t affect pressure and the ring around the barrel doesn’t mess with harmonics

 

[jerodmartinez]

thanks

 

[woods89]

I want to put together a lightweight hunting set up for mountain hunting. Will be used for elk, mulies and blackbears. I’d like to have to be able to take game out to 600ish yards with this set up. My son has a 6.5 creedmoor, but I have never owned a 308 or 7mm08 - I have always had big magnums until recently when I bought a 6.5 PRC.
What are your recommendations and why?

Do you reload?

I can get a 156 Berger to 2650 MV with Reloder 16 at 2.820 COAL with my 22'' 6.5 Creedmoor. If I had a longer mag box I think I could find a higher node yet, but I'm out of case capacity. That bullet stays above 1800 fps to a little over 600 yds at my elevation of 1000 ft. I would consider this a fairly capable combination, although my only experience with this bullet is up close, with a sample size of one. I don't want to imply personal long range experience with this one though, as killing targets at 400 yds and one deer at 80 yds is the extent of my experience with them.

 

[EmperorMA]

Do you reload?

I can get a 156 Berger to 2650 MV with Reloder 16 at 2.820 COAL with my 22'' 6.5 Creedmoor. If I had a longer mag box I think I could find a higher node yet, but I'm out of case capacity. That bullet stays above 1800 fps to a little over 600 yds at my elevation of 1000 ft. I would consider this a fairly capable combination, although my only experience with this bullet is up close, with a sample size of one. I don't want to imply personal long range experience with this one though, as killing targets at 400 yds and one deer at 80 yds is the extent of my experience with them.

As frangible as Bergers are, I'd suspect you might get decent performance a bit below 1800 fps, as well.