270 win vs 280 Rem

[Jamie6.5]

Agreed MR. I wouldn't use the term "overshadowed," but it's lifetime has been longer, and it's popularity was bolstered by Mr O'Connor.

One thing I will say about the .280AI is that I think it's great that the gun world has gotten excited about a cartridge that isn't the latest "magic magnumb."
(no offense Kirby )

But when SD, BC, delivered energy etc. are ALL considered, the two cartridges in std. (non-Ackley) config are practically ballistic/trajectory twins.
The .007" costs the bullet SD per same weight bullets, and in terms of BC/weight, the .270 holds a slight advantage.
Yes the 280 can use the 162/168/175 gr match grade High BC slugs.
But with 168s and 175s it will sacrifice velocity over the .270 with 150gr Hornady Interbonds, for instance.
The net result being two rounds with similar SDs and similar trajectories out to ~600yds, slight advantage -> .270.

Much beyond 6-700 yds one needs to go see Kirby or one of the other great rifle cartridge developers here at LRH and get something truly suited to taking elk class animals.

 

[fj40mojo]

I am curious about this line of thinking.
Do people really believe the .280 is great but the .270 sucks?
That .007 of an inch in diameter out of the same parent case must be the most valuable .007" on the planet.
The only reason .284 caliber bullets are as good as they are is due to the 7mmRM, not Remington's pump gun stepchild.

Winchester taught the world about the value of a mid-weight bullet at high velocity with the .270 almost overnight. It took 40 years, Ackley and Nosler to bring the .280 up to where it is today, and even Ackley didn't heap high praise on the .280.

I'll admit .270s could use a world class bullet in the 155-160gr range, but comparisons with the .280AI don't include the .270AI,...

Beyond that, any great advantage perceived in a 280 is just that,...
One's perception.

My $.02, YMMV.

It isn't the .007" greater diameter that attracts reloaders to the .280, it's the wider range of bullet weights available in the .284/7mm caliber. Yes, I concede that the .270 has the advantage for those who shoot off the shelf ammo and if you were to limit yourself to SAAMI pressures it still enjoys that advantage, but I don't know any reloaders that limit themselves in such a way. As a reloader I choose the .280 in Ackley form or original because it gives me a greater range of options and superior BC to the .30-06 in the same bullet weights. Perception is everything.

 

[Jamie6.5]

And if I handload a .270 with a Hornady Interbond (BC .525) and Magpro @3kfps you will be hard pressed to come up with a .280 load that beats it out to 600~700yds.
Good sectional density and energy delivered.
If you want to talk apples to apples, you have to Ackley the .270 also.

3kFPS is an Accurate reloading book load for the Sierra 150gr SPBT, out of a 24" barrel, NON-Ackley .270

Handloaders have been at with the .270 longer than .280 owners too! ;-)

 

[Edd]

And if I handload a .270 with a Hornady Interbond (BC .525) and Magpro @3kfps you will be hard pressed to come up with a .280 load that beats it out to 600~700yds.

Actually it would be quite easy to come up with a comparable 280 load. Just pick a comparable bullet that weighs about 10 more grains, I didn't look but Hornady probably has one. That's pretty much the only difference in the two cartridges. Whatever a 270 will do, a 280 will duplicate it with a 10 grain heavier bullet.

 

[Pistol packer]

ed, jamie-

go back to po's books. the reason why the 270 outperforms the 280 is the original point i believe. some very good points were brought out. however, ackley i believe brought out the best one after he tried the 270 ai. it is overbore at the top end of that statement. great increases of powder is needed to increase the speed even a few hundred fps. this is very detrimental to barrel life. it is why the 270 wsm burns barrels so quickly and gives small performance inc. over the 270 win.
the 270 ai was a "failure" even according to ackley. whereas, that small .007 in inc in diameter shows how much bore diameter is critical in overbore cases. the 280 ai is one of the gems hidden to the vast public. it can appoach or equal the 7 mm rem mag in most cases and no one thinks that you can do that with a 270 or even a 270 ai. the 270-300 weatherby shot a 150 gr at 3144 with 70 gr 4831 where as the 270 shoots it at 3010 with 56 gr 4350. although not the same powder, similar enough to show the large amounts of powder to increase vel. even a little. the 270 AI, he didn't even give data for because it was so marginally improved over the standard 270. whereas the 280 gets 2985 fps with 53 gr 4350 and the AI gets 3320 fps with 63 gr 4350. 350 fps with 10 gr more powder.
most of the books keep the 280 to 45-48,000 cup. whereas the 270 is boosted up to over 54,000. i imagine it is because of the pump that the 280 was introduced in. the 270 wsm gets almost 65,000 cup!!!
the 280 AI betters the 7 mm mag in the lighter bullets and still is almost equal in the 175 grainers. the 270 AI in 170 grainers would be hard pressed to break 2600 fps not even close to the 2850 fps the 280 AI does with 175 grainers.
that .007 in is very impressive.

the 270 is max efficiency for the 277 and the 280 AI is max for the 7 mm. the weatherby 7 shows this. a 154 gr in the AI shows 3070 with 60 gr. 4350 and the 7 mm weatherby shows 3139 fps with 71 gr of 4831 in lyman's 49th. again minimal fps inc for more powder (even tho different powders-close enough on the burn chart to see the point).

interesting discussion. maybe winchester will learn and put a 175 or even a 190 in their 270 wsm before it too goes the way of the 264.

doc

 

[backwoods83]

Pistol packer I see you're resurrecting a dead thread, btw the 270wsm and weatherby max at 65k psi not CUP, they have a 54kcup max same as a standard 270win, with more modern powders the 270 wsm, wby mag, 7mm rm, and 7mm wby mag are not considered over bore and they will do a lot more than stated, I have fired 162s close to 3200fps in a 7mm rm and also know that a wby is capable of 100+fps more, and before I sold it my 270wby would shoot 150 interbonds at 3320 or 140 accubonds at 3430fps with RE22. Most never find the true max, and every manual I have read always cuts the weatherby chamberings throats and usually kills them further by testing them in a 24" barrel. I'm just adding some truth in here for you, I'm not a 270 fan, I load a lot of 270 ammo for others but I personally don't care for them. Also if you're looking for the most efficient 28cal cartridge, the 284win with a long throat wins that catagory without being a magnum case, I have seen them do 3k+fps with 180 bergers and RE17.

 

[royinidaho]

If the 270 Win will do this then the 280 should do maybe a bit more???

http://www.longrangehunting.com/forums/f19/amazing-270-win-revisited-101209/

Still gathering data though....

 

[Pistol packer]

backwoods,

thanks. i forgot to look at the date on the thread.
the 270 wsm was in PSI, the others are in CUP. all was taken out of 49th ed. lyman.
agree totally on the rest. any good rifle today will stand 65,000 plus of pressure and all of the loads listed in the manuals are soft and often erroneous. i mentioned these only as references. will the 280 outperform the 270. can you put more water thru a 1 in or 1 1/2 in hose when the 1" hose is near max already.
thanks for clearing up those points.
the overbore consideration is proven. you can push anything to higher vel. if enough powder is used. the overbore means that the AMOUNT of powder needed increase noticably to increase a similar amount of velocity. the 270 win shows 140 grainer at 2982 fps with 54 gr 4350. the 270 wsm goes 2992 with 58.5 gr 4350, clearly not as efficient. that's an average of 55.22 fps/gr to 50.93 fps/gr for the wsm. IMR 4831 illustrates this even more--140 grainer in 270 win-56.3 gr fps 3010 fps; wsm 58 gr for 2954 fps (2 in shorter barrel), and the weatherby show 62.5 gr at 2897 with same length barrel showing considerable overbore. yes you can push them faster but a LOT more inefficent thats the definition of overbore. just a matter if you want more velocity and are willing to pay for it in powder, cartridges and barrels. the way you tell the max efficiency of a bore diameter is to inc. case capacity till the ratio of powder/velocity and you will see that that ratio remains fairly constant till the overbore limit is reached, at which time the powder levels go up for the amount of velocity obtained.

doc

 

[backwoods83]

Your right except what if the 1" hose has 65k psi and the 1.5" has 59k? Lol. Anyway yes bullet weight for bullet weight pressure for pressure the 270 has a slight advantage like the 140 accubond per say, the 27cal has a higher bc than the 28 but I also agree that the 270AI is a waste of time. Royinidaho's thread is a good read btw.

 

[Derek M.]

since this thread is up again, I find it interesting. I just received my 280 a few weeks ago. Been a hard core 270 fan for 2+ decades. Never even heard of a 280 until I bought my first Speer load book in 1990.

Anyway, I'll post more later but I have a 270 pushing Berger 150s at 3000-3050 fps. Rifle just happens to like the bullet with H4831SC. My 280 happened to really really like VV N165 and during the break-in process, it shot so well I did some confirmatory loads and got a duplication. Velocity is lacking but accuracy is stellar: 150 Btip 57.5 grains powder, Norma brass, 210M primers.

 

[FEENIX]

Anyway yes bullet weight for bullet weight pressure for pressure the 270 has a slight advantage like the 140 accubond per say, the 27cal has a higher bc than the 28 but I also agree that the 270AI is a waste of time.

Does that mean .280 AI is a waste of time too? lightbulb

What I can't understand is how badly the 270 improved is trashed, by people who don't own them, and the 280 AI is lauded.

They should be nearly identical. The 270 win has had a slight edge over the 280 with 140gr. The increase in performance according to some sources by making a 270 improved is 7.8%, the 280's improvement in performance is rated at 7.7%.

So how can one be a piece of crap and the other the best thing since sliced bread?

I understand there are heavier bullet choices in the 7mm, but as for shooting Nosler accubonds or ballistic tips, the bullets are too similar to differentiate.

It seems the people with them love them, and I think I am going to give it a try. IMR 7828 and a few others have breathed new life into the "overbore category", and I think the debate isn't over. So I'll spend a few dollars to make a fool of myself.

My current load in the 270 win with a 26" Douglas Airguage bbl, runs the 140gr nosler ballistic tip out the barrel at 3200fps with 60 gr of H4831. A hot load, but not rediculous. Use at your own risk. The same load will hold 3012 fps with a 22" barrel. I think the inclusion of a few more grains of powder-in a more effecient burning cartridge AND the 26" barrel will be a really cool long range weapon.

 

[bigngreen]

I kinda fail to see why it's a waste of time to launch .650+BC bullets 3000+fps, I know in a long range hunting situation you'll see the difference between a 270 Win and an AI or WSM.

 

[FEENIX]

I kinda fail to see why it's a waste of time to launch .650+BC bullets 3000+fps, I know in a long range hunting situation you'll see the difference between a 270 Win and an AI or WSM.

I totally agree! gun)

 

[Pistol packer]

come on feenix,

read my post before the last one. the 280 AI is superior to the 7 mm rem mag on light to medium bullets and just marginally slower with the heavier ones. it is the diamond in the rough. the 7 probably beats it out with the 175 or bigger bullets tho, but not much.

if any of you guys have any data on the 175grainers or bigger, i would like to compare to mine. H 4831 seems to work the best in mine.

you guys made my day. thanks for the laugh

doc