Home Forums Hunting & Shooting Long Range Hunting At what rane do ballistic coefficients matter. More than powder column for you?

Beyond the question of " what a person themselves feel is long range". We have the physics questions of.

1). How BC impacts energy and tracking
2). Recoil per bullet weight - if you are targeting a specific BC level or higher

But under normal conditions most of this BC thing is negated befor "x" yards.

What is the X for you

Completely depends on the round being shot.

At the point where a bullet with a crappy BC would be moved out of the kill zone in a 10 mph crosswind, and a bullet with a good BC would stay in.

SS,

For me it's the distance at which:

-I have a high level of confidence in being able to put the first round right in the boiler room.
-The bullet will arrive with enough velocity to ensure good expansion.

Condition dependent, the 1st criteria is about +/- 500 yards for me. I like to practice at much longer ranges than that though. Makes me a better shot at ANY distance. As a result I tend toward bullets that make the long distance stuff easier, VLDs, Scenars, etc. The upside is there are some very high BC bullets out there (Berger Hunting VLDs) that have given me noticeably quicker kills than more mainstream hunting bullets have for me. That's a win/win as far as I'm concerned. Easier to get hits with AND more DRT kills. Hard to not like that.

Back to the numbers. There's countless combinations of cartridge and bullet that you could use for comparisons, but I'll use the ones I shoot the most. I like them all for different reasons, but three of my favorite cartridges are the .270 , the .260, and the .308. The .270 will launch a 130gr Bullet at about 3100. My .260's favorite load will launch a 130gr VLD at about 2940. My .308's favorite load is launching a 155gr Scenar at about 2865. Drop is always very predictable but wind is voodoo. My #1 criteria is to put the bullet in the boiler room. Any bullet that minimizes wind drift is gonna help me the most with putting the bullet in the boiler room so let's look at where the BC of .260 load begins to overcome the muzzle velocity of the .270. When comparing the .270 to the .260, this is MUCH sooner than one might expect, especially given the 160fps muzzle velocity advantage of the .270. By 100 yards, the .260 has less wind drift than the .270 and the gap widens in the .260's favor from that point forward. The .308 lags behind both for a couple of reasons. Doesn't have enough case capacity to get really high muzzle velocities and you don't start seeing the really high BC numbers until you hit 200 gr or so. The .270 and .260 both maintain the wind advantage over the .308 from the muzzle all the way out.

I like impact velocity too. Ensures good bullet expansion. So maybe the .270 will keep the advantage in that department... For a little bit, but not terribly far. Before 500 yards, the .260 is hitting with more velocity than the .270. The .308 is starting out slower AND has lower BCs, so isn't even in the game as far as impact velocity goes.

The .270 uses quite a bit more powder than anything on a .308 case and the .308 is shooting heavier bullets than most other stuff on the .308 case. Recoil is pretty much a wash between the .270 and the .308, but the .260 handily wins in that department too.

For nostalgia reasons, I have really been itching to get a .270 again. For eagerness to please, barrel life and logistics reasons, I have really enjoyed shooting my .308. For performance reasons, I think I'm gonna screw my .260 barrel back on the Stiller�

John

To the OP: I like Hondo's answer better than mine, go with this!

Beyond whatever range you need to start correcting for drop/wind to get a good hit.

There is a specific break even point at which velocity loses to BC. It differs between cartridges and bullets though.

High BC bullets always help with wind.

Stated in such a way that all the replies are as meaningless as the question....some rethinking or rephrasing will be necessary to get a better answer to your quest.

OK, a little gack,

300 WinMag, 150gr Accubond 3300 fps, 4500ft el,



308 win, 208 AMax, 2600 fps, 4500 ft el,




In this comparison, the 308 with the slower high BC bullet is about equal (for practical purposes) to the 300 WinMag in drift and energy at 400 yards, and bests it past 400 in drift and energy.

Hondo that's a great post!

It was, but I think MM's was more telling, 3,300 vs. 2,600 fps, all there in black & white.

I'm in the 308/30-06 camp. But, when you mate a high BC bullet with plenty of powder, things get really good.

One of my shooting buds launches 215gr (BC .696) Bergers at 3000 fps from a 28" 300 WinMag. It's sick.

Spend some time on a ballistic's program

Spend even more time burning up some powder.

At 400-450 yards, you really start to see the high bc bullets start to shine, but if you shoot in high wind areas, the high BC bullets are the only thing that you should consider.

After hearing about the wonders of the 6.5 I checked to see if G.S.Custom makes a bullet for me. They do. The jump in BC caused me to order a new barrel, reamer and a few hundred 6.5 106 grain bullets (.516 BC). These will replace the .257 85 grainers (.383 BC) I now use.

Based on doing so many wildcats I think the velocity of the new bullets will be about 3,650 feet per second. Although the .257 starts 150 feet per second faster it looses quickly even in the short run. Arbitrarily I chose 2,200 feet per second as the minimum impact velocity. That means the .257 bullet runs out of steam at around 625 yards. The 6.5 bullet exceeds that by about 200 yards! Wow! The slower higher BC round, on paper, matches the faster lower BC round about 200 yards as far as velocity goes. Windage is better by the time they get to 100 yards! The 10 mile per hour wind drift at 600 yards for the .257 almost 25�. At the same range the 6.5 wind drift is only a little over 17�. 50% more for the .257. Really no contest.

These ranges are unrealistic for me at this time, but I�m putting my money where my desire is. Besides I think wildcatting is a disease I have.