Can anyone share their experience with this round. Accuracy, ballistics, etc. TIA.

9.3

No personal experience, but from dimensions, capacities, and standard pressure levels, I would start with manual starting loads for the 6.5x55 Swede. Cases are first cousins, close to twins. 257 is a necked down 7x57. 6.5x55 has a minutely larger head diameter. .257 has a slightly longer case. Basically they are equal with the 257 necked up.

Almost forgot: the 6.5 would require a faster twist barrel since most useful 6.5 bullet weights start just about where the .257's end. My 257 likes 100-117gr rounds, most 6.5's like 125-160gr. Anything lighter in 6.5 is usually designed for varmints.

I can't say about the 6.5 Roberts, but the 6.5x57 is basically identical. I have two Mauser '98 full stock sporters in 6.5x57, and both are extremely accurate with all the different 120-160 grain bullets that I have tried in them. I have never chronographed them, so I can't tell you much there.

In my opinion I believe the 6.5x57 to be a superior all around hunting cartridge to the 257 Roberts due to the heavier bullets available (if we are talking about game larger than varmints).

Jim

Buff375:

That's a big 10-4 on the 6.5x57. I've got a custom one built on a 700 LA with a 22.5" featherweight Douglas XX - loves the 129 Hornady with 45 gr Re19: an honest 5-shot MOA (or better) rifle with said loads.

In truth, I have a 257 Roberts as well (pac-nor barrel on a 722 action). I just love all those rounds in that diameter and ballistics class, so I thought I'd try the 6.5 Roberts too. Don't really want to go with the 6.5x55 as I don't really want the bolt face altered at all as I shoot a lot and often switch calibers when I switch barrels. Also already have a 6.5x55...

So many rounds and so little time...

6.5/257 Roberts is very close to the 6.5x57 but the problem of the 6.5x57 CIP is the deep throat for 160 gr rounf nose that not the best respice for top accuary with 120 and 140 spitzer or spizer BT

6.5x57 AMERICAN ( PPG reamer have a regular "short throat )

6.5x55 can do all the thing that can do a 6.5/257 without wilcat , you check case base US brand in 6.5x55 are smaller than Lapua and Norma and usual 6.5x55 chamber are broad ( military design )

good shooting and enjoy 6.5

DAN TEC