270 and Long Distance

[M.O.A.]

well now that i get to looking the hornaday SST and interbond both have a somewhat high BC of .525 for there 150s and the bergers are a little higher at .531 so thise may be ok at 1000 yards ;-}

[sortafast]

I have been going over and over what long action type caliber to do my 110 up in. Its a stripped action with the 30-06 sized bolt face. I thought about the 270, and in the short range, i like it enough, but like everyone has said, for LR stuff the bullets are lacking. I want to keep the 30-06 sized case so I was pretty well set on doing a 30-06 ackley improved, then someone brought the 280 Ackley Improved to my attention. Running some numbers in a ballistic calculator, it looks like the 30-06AI will stay supersonic to about 1000-1100yds depending on bullet choice and muzzle velocity. The 280AI can go to about 1500yds before going transsonic. I didn't really bother running the calc for the 270, but if you want to, the ballistic calculator on Vortex Optics site is free and seems pretty decent. Not only is the BC a big part of getting out there, you also want to take into consideration when the bullet will start to go transsonic. Thats when it will start to destabilize some and accuracy can start to suffer. From what I have read, this is around 900-1100fps depending on the atmospheric conditions.

[M.O.A.]

i would say go with the 280 AI it gits the most out of being inproved from what i have read i and is fastly becoming one i am looking at too ;-} that or the good old 7MM mag ;-}

[sortafast]

i would say go with the 280 AI it gits the most out of being inproved from what i have read i and is fastly becoming one i am looking at too ;-} that or the good old 7MM mag ;-}

ahh, but the 280AI gets just about to 7mm mag with out all the recoil, or so I am told.

[r3dn3ck]

I don't find there to be any real perceptible difference of recoil in similar weight rifles between several .30-06 based rounds and 7mag. My .270 felt identical to my 7mag though the 7mag has a significant amount more muzzle blast. None of them, even the 7mag kick exceptionally hard though I would argue that the -06 based rounds kick too hard for their performance and so the 7mag made more sense for me and I've been divesting myself of the .30-06/.270/.25-06 guns for the most part.

I don't know what loads people are running in the AI versions of the .280 but I don't see it getting full 7mag velocities (I could be wrong, it's happened before), maybe REALLY close but not all the way there. I think the biggest downside to the 7 rem mag is the rather large appetite for powder. Well... that and close range shots devastate a lot of meat when hunting mid-size and large mammals. As a paper puncher .280 might be better (I think we have an argument there for 7mm-08) but for anything against live targets I'd probably take the more common and powerful 7rem mag.

[helotaxi]

ahh, but the 280AI gets just about to 7mm mag with out all the recoil, or so I am told.

No free lunch. With the velocity comes the recoil. No way around it. That said, the 7mm Mag isn't a very hard kicker anyway. Not something I'd want to settle down behind for a long day at the bench but 20-40 rounds with a good recoil pad, even with a really light rifle aren't uncomfortable.

On the -06 format, don't forget the 6.5-06. For a given BC and SD, 6.5 bullets are going to be lighter than their 7mm counterpart meaning that velocity stays about the same, despite the reduction in bullet base area, and recoil is reduced. I'm in the 280 AI camp personally simply because I already keep 7mm bullets on hand (though my next project is my long range hunting rifle in 7 WSM) but if you're not already committed to a certain caliber, it's worth a thought.

[FUBAR]

Someone said long range shooting is speed, well many with speed just fall off...

No revaluation, but it's-- speed + weight + BC. ( I would add sectional density for long range hunting)

However, tell that to the guys shooting 45-70s and such out to 1200 yards, with iron sights! Plus they have been doing it for 100 years or so!

A 270 will serve you well, study the published load data, and work yourself up a load. That's what's fun to me, getting the most out of each rifle...

Just for the record, I have a very fine 7mm mag, and a very fine 280AI. I consider my 280AI one of my very favorite rifles, of all my rifles, not just compared to the 7mm mag-- and I love overbores!

[helotaxi]

Other than energy on the target, weight has nothing to do with it. You can predict the flight of a bullet without knowing anything about the bullet's weight, in fact. All you need to know and all that matters WRT bullet trajectory is muzzle velocity and ballistic coefficient. Despite what seems intuitive, bullet weight doesn't have anything to do with wind drift.

The reason that the 45-70 was shootable to those ranges with the low BC bullets that they shoot is that the low muzzle velocity means that the bullet doesn't lose that much velocity as it goes downrange. Wind drift is proportional to velocity loss. An interesting exercise in that vein is running the wind drift numbers on the .300 Blackout shooting a subsonic 220gn SMK.

[FUBAR]

The reason that the 45-70 was shootable to those ranges with the low BC bullets that they shoot is that the low muzzle velocity means that the bullet doesn't lose that much velocity as it goes downrange.

What???

Some of those old 250 or so grain bullets have about 3000 fps muzzle velocity and are down to 600fps by the time they reach 1000 yards and in the 500fps range at 1200 yards.

In fact they have lost Half their muzzle velocity in the first 300 yards!

Ok if we forget "weight" as a factor in windy conditions, I understand the argument. There is no way however to exclude "weight"--without a certain sectional density the projectile will never have a design that supports the BC nor withstand the launch....

[handirifle]

To my knowledge there never has been a 45-70 round loaded with a 250gr bullet at 3000fps. Barnes has an X bullet that weighs 250gr but it is the only one that I am aware of.

The 45-70 was so effective, BECAUSE of the bullets weight. An object in motion, tends to stay in motion. Newtons law, and thus the heavier the object is, the harder it is to stop. Velocity is a factor, but if velocity and BC was the end all, then one would be unable to explain why a 400gr (typical bullet weight) 45-70 bullet will penetrate 8-10 times as many water filled milk jugs of say a 243 and a 100gr bullet. It's called momentum.

There is a documented test of the 45-70 at over a mile, where a 400gr bullet at around 1300fps MV, was fired into a 4" thick wood target over a mile away. The bullet went completely through the target and over a foot deep in the sand behind it. Which is easier to stop, a train doing 30 mph, or a car doing 60?

Slam a car doing 60 into a 5000lb car and it will stop in a few feet after impact, slam a train doing 30 (or 20 for that matter) into a 5000lb car and 1/2 to one miles later it will stop. Momentum!

[Panozguy]

You guys are getting over my head quickly, so I'll just keep it simple. Of all the people I know who shoot at distance, not one of them shoots a .270 at the range - and we're talking a lot of people here. .308? Sure, plenty of 'em. 7mm, 6mm, 6.5mm variants? Sure, plenty of them. Even .223. But not ONE single .270.

Buy what you want, but there must be some reason for this...best of luck, OP.

Edit - I mean long distance target practice, not hunting. Punching paper or steel, which I believe was the original purpose of this thread.

[FUBAR]

Your right, there is only a couple and we are not talking lever guns with short barrels... even with a "Quigley" type Sharps rifle, 45-110 & 34 inches of barrel, no one would use a 250 gr bullet, even though the could get amazing muzzle velocity.

My point was even with a 45-?? it takes mass/weight/SD, around 400 gr, to support the design/BC and maintain velocity....

My 6-284 uses a 1-8 twist barrel by design, in order to use the highest weight/BC bullets made, and it is no fluke that the 117 gr DTAC has the highest BC (600)

However drop the powder and velocity a bit and my 6-284 is routinely out shot by the other more common Benchrest 6mm's at 1000 yards

The above fact is not an issue for me because I'm not concerned with fractions of an inch at 700 yards, I would rather have SD and energy, but that's just me:cool:

[358Hammer]

"Even .223. But not ONE single .270."

Fubar has a wonderful example: There are a number of ways to accomplish a given task and his is just one way. When the 270 first came out it was one of the fastest kids on the block and writers with sharp pens made it something even better than it was. Bullet technolgy was way behind back when the 270,308 Norma Mag and the various fast cartridges were wounding game because of inferior bullet construction..

Technology and knowledge advanced and for various reasons (money) high BC bullets for the 270 Winchester were down on the money scale and the screaming 270 ballistics just kind of got put on the back burner when the 300's were eating up the long range circle.

When the first 223 won a long range match I am sure it was a novelty and many just smiled thinking it was a fluke. When that same gun did it again some started paying attention. Trends start and stop in the winners circle. When we started improvong that little 6 BR case there was a reason. Then someone took that little case concept and here was the 6.5 X 47 Lapua.

Now that the 270 has the bullets to compete it just needs someone to believe in it and start competing with it.

Neal

[Panozguy]

"Even .223. But not ONE single .270."

Fubar has a wonderful example: There are a number of ways to accomplish a given task and his is just one way. When the 270 first came out it was one of the fastest kids on the block and writers with sharp pens made it something even better than it was. Bullet technolgy was way behind back when the 270,308 Norma Mag and the various fast cartridges were wounding game because of inferior bullet construction..

Technology and knowledge advanced and for various reasons (money) high BC bullets for the 270 Winchester were down on the money scale and the screaming 270 ballistics just kind of got put on the back burner when the 300's were eating up the long range circle.

When the first 223 won a long range match I am sure it was a novelty and many just smiled thinking it was a fluke. When that same gun did it again some started paying attention. Trends start and stop in the winners circle. When we started improvong that little 6 BR case there was a reason. Then someone took that little case concept and here was the 6.5 X 47 Lapua.

Now that the 270 has the bullets to compete it just needs someone to believe in it and start competing with it.

Neal

Point taken. And for the record, I actually hope it works! I'm not in any way hating on the .270. I would happily own and shoot one at the range if it proved to be superior to what I already own.

[helotaxi]

To my knowledge there never has been a 45-70 round loaded with a 250gr bullet at 3000fps. Barnes has an X bullet that weighs 250gr but it is the only one that I am aware of.

The 45-70 was so effective, BECAUSE of the bullets weight. An object in motion, tends to stay in motion. Newtons law, and thus the heavier the object is, the harder it is to stop. Velocity is a factor, but if velocity and BC was the end all, then one would be unable to explain why a 400gr (typical bullet weight) 45-70 bullet will penetrate 8-10 times as many water filled milk jugs of say a 243 and a 100gr bullet. It's called momentum.

There is a documented test of the 45-70 at over a mile, where a 400gr bullet at around 1300fps MV, was fired into a 4" thick wood target over a mile away. The bullet went completely through the target and over a foot deep in the sand behind it. Which is easier to stop, a train doing 30 mph, or a car doing 60?

Slam a car doing 60 into a 5000lb car and it will stop in a few feet after impact, slam a train doing 30 (or 20 for that matter) into a 5000lb car and 1/2 to one miles later it will stop. Momentum!
Bullet weight is captured insomuch as it matters for exterior ballistics in the bullet's BC. BC is made up of two components: sectional density (SD) and form factor. Weight only matters as a ratio with frontal area. That is the definition of SD. If you don't believe me run a ballistics curve on a bullet of your choice and then make no other changes to the inputs (same BC and velocity) and reduce the bullet weight to 10gn. You'll notice that other than energy absolutely nothing changes with regard to bullet drop or wind drift. Two bullets of the same BC fired at the same velocity will fly exactly the same even if one weighs 200gn and the other 50.

The same principles apply when examining terminal ballistics and penetration. Target penetration is determined by SD and velocity. Bullet expansion affects SD, so the rate of bullet expansion affects penetration. That means to get a meaningful comparison between bullets you need bullets of the same construction that will expand the same. Assuming that you have that, bullets of the same SD impacting with the same velocity, will penetrate the same regardless of weight.

Momentum matters, but it is certainly isn't the only factor. You have to account for resistance. That's why SD matters. Resistance/drag is proportional to the frontal area of the projectile. SD corrects mass for frontal area so you're comparing apples with apples. Why flies farther, a javelin or a shot put? The shot weighs more. Which would you rather be hit with assuming that they're traveling the same speed (given "neither" would be my choice, but anyway). Man quit hunting with thrown rocks once he developed the spear. He could throw the spear farther and it certainly penetrated more when it hit something, even though it weighed less.

[sortafast]

No free lunch. With the velocity comes the recoil. No way around it. That said, the 7mm Mag isn't a very hard kicker anyway. Not something I'd want to settle down behind for a long day at the bench but 20-40 rounds with a good recoil pad, even with a really light rifle aren't uncomfortable.

On the -06 format, don't forget the 6.5-06. For a given BC and SD, 6.5 bullets are going to be lighter than their 7mm counterpart meaning that velocity stays about the same, despite the reduction in bullet base area, and recoil is reduced. I'm in the 280 AI camp personally simply because I already keep 7mm bullets on hand (though my next project is my long range hunting rifle in 7 WSM) but if you're not already committed to a certain caliber, it's worth a thought.

I am not worried about recoil. The rifle is going to weigh 10lbs or better and I am going to run a brake and eventually a can on the end. I am pretty sold on the 280AI right now. Still kind of want to do a 30-06AI just to see what kind of difference I can get with it and how far I can get it to stretch it's legs. But I have been told that once you do one Savage you start working on another, not that its a bad thing, other than keeping my wife happy.

[handirifle]

helo taxi
I agree in part with your statement. The part I do not agree with is the comparison of a 200gr and a 10gr bullet with the same BC is virtually impossible in the firearms world. A 10 gr bullet with the same BC as a 200gr bullet, say in 30 cal, would be the shape of a sewing needle

Again, I will match a 400gr .458 bullet at 1600fps against a 30-06 180gr bullet, any day of the week when it comes to punching through gallon jugs of water. Use a FMJ 30 cal bullet so expansion do not interfere with penetration. I have seen it done MANY times, you'll see the .458 bullet pass through 10-15 jugs and the high velocity, high BC bullet will be lucky to go through 6.

The big slow heavy bullets DEFY the "normal" theories of what makes a bullet penetrate.

You want examples, go to the http://www.garrettcartridges.com/luposafaris.htmlGarrett Ammo website and click on Lupo Safari's link. Read what the lowly 45-70 does to animals like the Rhino, with a bullet traveling at under 1600fps. There is no way in the world a 30 cal bullet at 2700fps and with a 550 BC, and 200gr weight would even come close.

[handirifle]

I am not worried about recoil. The rifle is going to weigh 10lbs or better and I am going to run a brake and eventually a can on the end. I am pretty sold on the 280AI right now. Still kind of want to do a 30-06AI just to see what kind of difference I can get with it and how far I can get it to stretch it's legs. But I have been told that once you do one Savage you start working on another, not that its a bad thing, other than keeping my wife happy.

I think the 280 AI is a great choice for what you want, whether it's paper or elk. Good bullet selection, good cartridge. The AI was standardized because there is no worry of overloading rifles originally chambered in 280.

[helotaxi]

helo taxi
I agree in part with your statement. The part I do not agree with is the comparison of a 200gr and a 10gr bullet with the same BC is virtually impossible in the firearms world. A 10 gr bullet with the same BC as a 200gr bullet, say in 30 cal, would be the shape of a sewing needleMerely an extreme example to demonstrate that weight itself has no bearing on external ballistics. If you want a real world example, take the .224 53gn Vmax fired at 3400fps from a .223 and compare it to the 75gn Hornady HP fired from a .243 Win again at 3400fps. The BC's of the two bullets are almost identical and they are fired at the same velocity and will have the nearly identical trajectories dictated by their difference in BC even though they are different weights. Likewise, compare the 105gn Hornady BTHP from a .243 @ 3000fps to the 178gn HPBT from a 300 Win Mag also @ 3000 fps. They have the same BC and will fly exactly the same despite the 70% difference in bullet weight.


Again, I will match a 400gr .458 bullet at 1600fps against a 30-06 180gr bullet, any day of the week when it comes to punching through gallon jugs of water. Use a FMJ 30 cal bullet so expansion do not interfere with penetration. I have seen it done MANY times, you'll see the .458 bullet pass through 10-15 jugs and the high velocity, high BC bullet will be lucky to go through 6.

The big slow heavy bullets DEFY the "normal" theories of what makes a bullet penetrate.

You want examples, go to the http://www.garrettcartridges.com/luposafaris.htmlGarrett Ammo website and click on Lupo Safari's link. Read what the lowly 45-70 does to animals like the Rhino, with a bullet traveling at under 1600fps. There is no way in the world a 30 cal bullet at 2700fps and with a 550 BC, and 200gr weight would even come close.
The bullets defy nothing. This is physics, not "notions". You're ignoring the most important part which is for the comparison to be valid, the bullets have to be of like design and construction. The large monolithic solids don't expand. In reality, the 150gn FMJ from a .308 does. Its spitzer design causes it to yaw when it hits the milk jugs and the bullet then usually rips apart at the cannelure. The yaw changes the sectional density drastically because now the side of the bullet is the frontal area. Fragmenting changes it even more drastically since now each fragment is a "bullet" unto itself with a very low sectional density. In contrast, the .458 solids, don't expand and their blunt shape also keeps them from yawing. The result is a constant SD and deep penetration. It performs exactly as the physics dictates that it would. If you had a similar .308cal bullet, shape and construction, with the same sectional density, it would weigh less (180ish grains to have the same SD as a 400gn .458 slug) but impacting at that same 2700 FPS, it would penetrate deeper.

Whether you agree or disagree, those are the facts. Don't just take my word for it. Do some research. Ge a copy of Applied Ballistics for Long Range Shooting. Bryan Litz, the chief ballistician for Berger Bullets, breaks all this down into simple terms. It's a very enlightening read from a guy with not just credibility in the shooting world but also with an aeronautics, physics and engineering background to back up what he's saying.

[r3dn3ck]

I was the one that said velocity is all that matters and I was perhaps a little heavy handed in my phrasing on the matter but the fact of the matter is that strictly speaking about drop, the more velocity retained over x period the lower the drop period. Helotaxi has done a fabulous job in explaining the physics behind this to everyone for me which I thank him for. All else being equal a bullet that retains velocity longer time will make it not only further down the road but be affected by gravity exactly the same as a slower bullet over the same period time. A slow bullet and a fast bullet get to different horizontal distances over X period time. During that time span they will drop the exact same amount, they will simply have gone different distances before doing so.

The basic ballistics equation evaluates and then integrates complex data sets. If you really look at the equations and apply the various algebraic properties to the elements of it such that you isolate what it's really doing at any one place, it is mapping the Horizontal-position@time slope against a Vertical-position@time slope (and this is why bullet time of flight is a part of the output data set) and to then display nothing more than gravity's effect on vertical position based on roughly 32ft/s/s acceleration given the time of flight. The particular horizontal distance achieved over period time X is only relevant as an output value when analyzed against the vertical position at the same time. If the calculation was going to try to be precise it would have to take several other factors into consideration which most calculators don't more or less because it can't easily be done with the sorts of vague generalities and coarse rules of thumb we already use still in play. Yes, there are phenomena like spin-drift and the tendency of certain bullet shapes to fly in a very different attitude with respect to their direction of travel at long distances but those as well are not easily worked up into a calculator you can use on the web.

There is a small subset of participants in this thread that have managed to confuse terminal ballistics with external ballistics and momentum with a number of things. To those folks: please try to keep the thought muddle under control and you'll find that the concepts are then very easy to fully understand with only a modest recollection of high school algebra and physics classes.

I am not a ballistician but I did sleep at a holiday inn once and I used to be a math geek. Thankfully I've forgotten all the really fun parts of math and have gone on to better things, like shooting debris just to see if I can hit it.

OP: none of this is relevant to your needs or question. Basic advice, if you want to use a .270 then stick with bullets on the heavier end of the available weight options and plan to spend on those high-BC bullets which will maintain velocity better over time and make your come-up values smaller. Handloading will almost certainly be required to get the most out of your time at 1K yards. Don't hunt at that range with that gun. Yes it's lethal, no it's not a good idea or ethical by modern standards.

EDIT: for those that want to do the math, here's a nice page showing all the bits and where they're working and HOW they're working. http://www.grc.nasa.gov/WWW/k-12/airplane/flteqs.html