I have been thinking of getting a smaller, handier rifle for this fall, a sort of mountain rifle in 26 - 30 caliber. The barrels on these can be around 18 - 20 inches, so my question is, what would be a better suited cartridge, an older one such as 6.5 x 55 swede or 7 x 57 that operates at lower pressure, or a more modern one like a 260 of 7mm-08? Or does it even matter?

When the 270 win. was first designed they found that the barrel lenght that it shot the best out of was 22",would that be short enough for you? It,s a real good cartridge as well. vangunsmith

Take a look at the Ruger frontier rifle,you can get this in the .300 wsm.I have no clue what the performance would be with that short of barrel probaly like a 30-06 I suppose.
If I was using a short barreled rifleI would look at the .308 win,358 win,350 Rem Mag,or custom 450 Marlin.
BBJ

Take a look at the cartridges loaded in the encore and contender. The 7x30 waters. 7MM-08, 308,35 Remington. The 7x57 and 260 should work pretty well however the 260 performs best with bullets like the 120 BT at pretty good velocity. I quess the 7MM-08 is one of the better performers. And would be my choice.

Short barreled (carbines) are sweet handling guns anywhere the cover is heavy or there is some demand for fast handling.....but don't think that short barrels mean short cartridges. A short barreled .270, .30-06, or even .35 Whelen is a superb choice for the thick cover hunting.

While the .260 7MM-08 or even .308 are great cartridges, there's nothing about them that excell in short barrels over their longer counterparts.

I have seen some evidence to suggest that the WSM/SAUM calibers can develop quite a bit of speed in a short barrel. The short, fat powder column thing . . . .

The biggest cartridge I would use in a 20" or shorter barrel would be a .350 Rem Mag or any of the WSM's.
Ive come to notice that a .300 WSM gettin 3000fps out of a 22" barrel will get about 2880 out of a 16.5" barrel (ruger frontier). Thats still pretty fast.

OK, thanks for the info! I read somewhere that the 25-06 is at it's best with barrels no less than 24 inches, so I was thinking that maybe a longer barrel was needed for similiar cartridges to significantly outperform something along the lines of a 7 x 57. I have only one gun with a short barrel (AR-15 with 16" barrel), but even that little cartridge gives off quite a muzzle blast, which I could be mistaken for wasted energy.

If I were doing to pick a cartridge for a short barrelled rifle (</= 20"), I wouldn't choose any cartridge that had the word "magnum" attached to its name. I'd stick with a short action cartridge that burnsabout 50gr or less of a medium to med/slow powder.Any of the cartridges in the.308 Winchester family (ie .243Win, .260Rem, 7mm-08, .308Win) would be well suited to such a rifle.

Mike

Bingo ! shorter cartridges are more efficient at burning powder, and will have less loss of bullet speed in shorter barrels. I think. LOL