As far as I know, no one ever paid O'Connor to use or endorse the .270 cartridge. He used it because it worked and that's how he wrote it.It shoots flat and has a mild recoil to it. It works well on the game he felt it was suited for (moose, on down).He shot it very well.
Jack wrote about all of the contemporary cartridges of that day, but the .270 saw a lot of use and therefore a lot of print.
While still in high school in the late 60's, I bought my own .270, based much on Jack's recomendation.
I, like many of you, own lot's of rifles now. Mine range from the .204 to the .338 mag and .358 win. I use and enjoy them all, but if I had to keep just one...It would still be my .270. Nostalgia? Yeah, some for sure. But mostly because it still just plain works and I see little point in anything else.
I still have a box of those old Speer 170gr rnd nose bullets. I might just load em up and see how they handle an elk. BT53

My primary rifle has been a 270 Win since I got my first one in 1958. I have used it in 4 states, 3 Canadian Provences, Mexico and 2 African Countrys. With it I have taken 14 elk, 2 moose, 3 black bears, 11 pronghorns, 4 sheep and I don't know how many mule deer and whitetails. In Africa it has taken PG that range in size from gray diker to Kudu. I have only lost one wounded animal with it. That was a spike bull elk that I creased on top of the back. I would have lost that elk, if hit in the same place with a 458 Lott. I have used several brands of bullets but none have worked better than the 150 Nosler Partition.

465H&H

Truvelloshooter: I have used various 270 Winchester calibered Rifles for 4 decades now. I have retired TWO different 270 Winchester Rifles! They simply had killed more than their "share" of Big Game!
I now have another splendid Big Game Rifle in the form of a long, heavy barrelled, Remington 700 Sendero, in 270 Winchester! This superb Rifle is not only accurate, it is a joy to Hunt with on the high plains and the foothills of the Rocky Mountains! Many of my recent kills with this Rifle have been far in excess of 300 yards! The 270 Winchester IS up to this task as witnessed by my long string of one shot kills with this Rifle!
Over the years I have killed three species of Deer (Mule Deer, Blacktailed Deer and Whitetailed Deer) with the 270 Winchester! Along with the Deer I have taken MANY Antelope as well as Mt. Goat, Elk and Bear with my 270's!
It is simply a splendid caliber and it performs splendidly well on Big Game - with proper shot placement!
I hope some day soon to add Caribou to my list of Big Game taken with the 270 Winchester!
The 270 Winchester may seem "boring" to some but its proven abilities continuously "impresses" me!
I have Big Game Rifles using cartridges in various calibers - like 257, 264, 284 and 308 (along with some others!) and I simply would rather be found dead, than found without a Rifle in 277 (270 Winchester)!
Bullets weights in the 270 Winchester that I have shot came in weights from 90 grains to 110 grains to 130 Grains to 140 grains as well as the 150 grainers! And I have seen offerings in 100 grains, 160 grains and 180 grains as well for the 270! That pretty well covers things from Rock Chucks and Coyotes to Moose and Grizzlies!
Long live the outstanding 270 Winchester cartridge!
Born in 1925 (81 years ago!) it will soon enough reach the status of "century old" and I am sure still be among the most popular and best Big Game cartridges available! Last I heard it was THE second most popular cartridge for Big Game Hunting behind only the 30/06!
There probably is a reason for this? Like maybe low recoil, great accuracy, good bullet selection, long brass life, long barrel life, great brass life, good projectile speeds, flat trajectory, etc etc etc!
Yeah nothing much wrong with the 270 Winchester at all, based on the results from my four decades of useage!
Jack WAS right!
Hold into the wind
VarmintGuy

Not positive but I think its illegal to live in Texas without one.

Guys:
Since there was a little conversation about the velocties one might achieve with a 26" Sendero, here is what I am getting. With a 130 Grain Ballistic Tip, and IMR 4831, I am getting 3250+. Last time I was at the range, one of my rounds cronographed @ 3413fps. I don't have any idea where that fast one came from, as I always weigh every charge etc. Groups run in the 5's and 6's.

As to the heavy bullets in 270, I think a guy needs to watch his twist carefully. If I remember, the old 170's were round nosed, which isn't exactly a long range bullet.

Good Shooting

Jerry

I have never taken an animal with a .270.
I had to buy 3 of them before I could get one I liked.
The third one is a keeper.
It shoots about any 130 or 140 grain bullet close to MOA. Its a 1952 FN. It is prety as hell and I (an old leupold guy from way back) put a 3X10 Weaver grand slam on it. Grea combo.
I get 3012 with a hornady 130 grain SST and it aways puts 2 through the same hole and 3 into .75 to and even inch.
If I can get a barnes tripple shock to shoot like that I may take it after Elk, Even though I have a .338 win and a 35 Whelen.
If I had to live with just 2 rifles,
I think I would go .270 and My Marlin 45/70.
...tj3006

TJ:
Interesting, in my 24" Model 70, and with a 130 grain bullet, I am getting around 3040. Pretty similar results to yours. As to the 270 on elk, I have killed one and my son the other with our 270's. Steve shot his with a 130 grain Norma factory round, I shot kill at about 75 yds. I shot mine with a 130 Winchester bullet, 80 yds, one shot also. That bull went down faster and more hard, than any of the other 8 elk I have shot.

Jerry

I'm still a very happy .270 Win user. Don't think there is a better all around deer/medium game load available. Very accurate, flat shooting, easy to load for, light recoil, and devastating on game...what more could you ask for?

-Lou