Smallfry,

Comparing the 270 and the 7x57, in factory fodder isn�t much of a comparison. One is loaded to much higher CUP pressures, and the other is intentionally under loaded by the ammo manufactures. Based on the above though you are certainly correct and I would expect the 270 to outperform the older round.

Using hand loads the differences level off. Trying to keep this in an apple to apple comparison is going to be a little difficult, as the 270 Win with the classic 130 gr bullet @ 3050 fps is a great combination of both bullet and cartridge. And the 7x57 isn�t at its best performance with this light of bullet and needs 140-150 gr. bullets to be in the best loads. Trying to keep this as a close comparison I will use the 140gr bullet in the 7x57.
The 270 bullet has a SD of .242 and the 7mm is .248 this is for Nosler Partition bullets, I use this as representative, use whatever bullets you choose.

Hand loaded the 7x57 can be loaded to 2900 fps with a 140 gr bullet. So the difference is about 150 fps in practical terms. Using this as data, I feel there not much difference on game to 150 yds, it�s a wash. After 200 yards the 270 gets a clear advantage and that will carry out to any distance you feel comfortable shooting at. Clearly the 150 fps gives the 270 the edge at those distances. But I hunt dark timber a lot and shots are usually under 100 yards, at these ranges I think they both perform about the same. I actually use 150 gr bullets and these are obviously slower, but at under 100-125 yards these two cartridges are similar in performance.

Jack O Conner who was certainly the 270�s biggest advocate, thought very similar thoughts. I can�t quote it at this minute but in a week or so when I get home I can dig through may reloading room and support that statement.

Magnum comparison is another discussion.

Smallfry,

This is the first of the mag installments. I will discuss them seperately as I feel if I blank compare the two cartridge comparisons you listed it will bias my answer unfairly.

Concerning your comparison of the 6.5x55 to the 264 Winchester. Again I want to assume you are using at a minimum Norma loads, or handloads on the 6.5x55. The American factory fodder in this cartridge is held to very low pressure, and velocity suffers because of it. I am also hesitant to use factory numbers of the 264 mag, as the current loading for this cartridge are at least 100 fps slower than in previous years. What is published currently is at least real numbers and the old factory loads were highly suspect of published velocities. Winchester published 3200 fps, but Speer Laboratory chronographed 3139 fps ( 26" tube), and Lyman documented 2958 fps ( 24" tube ) ** Source Ken Waters pg 186 Pet Loads. Current loads are listed as 3030 fps with 140 Remington or Winchester load.

This is further complicated by the fact that Winchester used two-diameter bullets, meaning the front half of the shank is smaller diameter than the base section. This helped Winchester keep the pressures down on this cartridge while getting velocity they desired. This is great for Winchester but your average reloader can only match velocities if they are using original factory bullets, as no other manufacturers design bullets that way.

Because of this fact alone I will use factory as the standard for the 264, as it is difficult to better the velocities on the reloading bench.

So the 264 Win Mag has somewhere between 2958 and 3139 fps. with a 140 gr bullet. I think both Speer and Lymans numbers are valid and the diferences I attribute to this very overbore cartridge, and severe loss of velocity when reducing the barrel length.

The 6.5x55 in Norma factory ammo has 2789 fps with a 140 gr Nosler bullet. Hornady's new light mags are very close to that. I don't see much improvement in this load when reloading unless the barrel has a long chamber and bullets are seated not as deep and the cartridge is above the COL factory ammunition.

So at worst we have 350 fps difference in velocities and at best 169 fps. This in my mind makes virtually two seperate outcomes. And comparing these two is further convoluted by bullet construction. Very few 6.5mm bullets were designed for magnum use, there are some but most were designed with the 6.5x55 and the 6.5-06 in mind.

Never-the-less, on the 169 fps spread above I contend this is a pretty similar comparison as I did in the 270/7x57 case previuosly posted. No real benefit a 150 yds or less, while above that range the 264 mag is superior.

With the 350 fps factored in the situation changes somewhat, the 264 Mag is the clear winner at longer ranges
and this is a true 500 yard cartridge. But on under 100 yard ranges I think the 6.5x55 is a superior killer. The 264 mag has bullet problems, a sturdy enough bullet to hold together and they zip right through game with no expansion, a bullet that doesn't have the sturdy construction wants to explode or break apart at short ranges. Clearly the 264 Mag is not a good dark timber cartridge, but it is an outstanding antelope and long range mule deer cartridge. Moving into a 156 gr bullet helps in this regard but that is another seperate comparison and there is no factory ammunition available.

I admit the 264 Mag is not held in high regard by me, it is very overbore with short barrel life, it tends to be very fussy on component choice when reloading or accuracy suffers, and expect 55-75 fps reduction in velocity for every inch of barrel under 26". With a 22" barrel your 270 is a better cartridge/rifle combo. I have always felt that this is an example of letting engineers play, it does one thing and one thing well, similar to a formula one car, don't expect it to run on regular gas or drive on a gravel road.

In my opinion if you want to increase the velocity in a 6.5mm bullet use a 6.5x284 or a 6.5-06, and no I don't discount the benefits of extra velocity an extra 200 fps is a good thing. But in this caliber especially it is a very fickle benefit, as most of the bullet making world designs bullets for the 6.5x55, 200 fps doesn't concern me but 350 fps needs a different bullet construction and these are difficult to find.

* Note 7mm's next but not tonight

I pretty much don�t concern myself with the 264s, 7X57s, 270s, 6.5X55s killing time. They are all reasonable, it�s just that I see a difference, and it�s at all ranges from 0-300 yards.

We have a different take on allot of things, you seem to think the "magnums" or higher velocity cartridges only have an "advantage"(kill faster?) past 150 yards... I don�t. You seem to think that a 264 would not be a good dark timber rifle; I do... so much so that there are many identical bullets that the 264 and 6.5X55 could both use where the 264 would always out penetrate the 6.5X55, even at the closest ranges. You seem to think 156/160 grain bullets penetrate well... I don�t, and have shot a small handful of critters with several brands... the toughest being the Hornaday which penetrated a whopping 15" into a javalina at 2300fps. In five cases 125 and 140 grain partitions have out penetrated every 156/160 I have used. You seem to think that a 200 grain partition from a 300 magnum will pencil through a deer, I don�t, and witness this every year because this is the only bullet I choose to shoot in my 300. I assure you a hole the size of the bottom of a coffee cup will be blown right through even a pronghorn, and less than that on larger game. I see animals living longer and traveling farther when shot with slower similar cartridges, especially with smaller bores... gee what a surprise. If you haven�t noticed though... I hunt quite a bit with such fast stepping cartridges like the 250 savage, 30-30, and the 6.5X55... and haven�t felt that they are wanting cartridges.