If you own a modern rifle chambered for 6.5x55 (a rem 700, win 70, CZ550 ...), and you load this cartridge to a similar pressure than 6.5-284 (around , 63,000 psi), what performace do we expect from the old swedish round compared with the new one (6.5-284)? I understand this rifle is safe for this pressure because there are modern chamberings (270 win ...) in those models.

A 260rem can be loaded to within 100-150fps of a x284. You should be able to come to within 100fps with the swede.

I've made a check with Quickload v3.4; the max pressure for the 6.5-284 is 4,100 bar/59460 psi and at that pressure level, the difference of V/0, between the 2 cartridges, with a 140gr bullet, seems to be 35-40 m/s. Of course it's only a guess!

P.S. Actually the difference seems to be smaller, 20-25 m/s.

"swede"? This is a norwegian and swedish cartrigde. Today many ignorant people in the US and other places call it a swedish round and download it to anemic levels (6,5x55 swede).

Disregard any such loaded ammo or load-data.

Modern load data puts the 6,5x55 at 2700+ fps with a 140 grs bullet. Like the 140 grs Nosler partition loaded with 49 grs of MRP@2770 or 50 grs N165@2735. Or the 120 grs Sierra loaded with 53 grs of Reloder 22@3000 or 49,5 of N160@2935.

You can shoot out to 1200m with the 6,5x55 if your`e into long range shooting.

I'm a big fan of the premium 120 grain bullets.

I load Northfork HP 120s to 3,040 FPS from a 21" barrel on a '98 large ring VZ-24 in 6.5 X 55, and I use H-4350 powder.

This is a very flat shooter! The 6.5-284 might do better but I'm betting not a lot!

A 6.5x55 improved shooting 129gr hornady interlocks in an old cut down m96 military rifle is my everyday working gun.The case capacity is almost the same as a 284, it shoots long and flat and very accurate,and I can get brass for it anywhere.When I first built it I chrono'd a few loads and it was doing the same, if not better speeds than my mates 270.
Just blow out your '55 case, you can't go wrong.



As you can tell I'm a 6.5 fan,from left to right....6.5x39...spanish '94
6.5 zipper imp...99 savage
6.5x250...vergueiro carbine
6.5x55 imp...m96
6.5x284...sample round (don't need one)
264 RCBS...m70


Roger

I'm getting 2800fps from my 21" barelled 6.5x55 Scultz&Larson using N560 and 140 grn AMax.

This is a modern and very strong action.