FN states that 308 ammo can safely be fired out of the Scar 17S and its 7.62 NATO chamber.
I have fired Federal Premium Gold in 308 168gr.and was shocked with the accuracy from the Scar.It was so good that I had Swarovski make up turrets for the scope for this cartridge.
Now I wonder if I should be looking at working up a load in 7.62 NATO since this is what the rifle chamber calls for. Accuracy is the goal.

If I decide to shoot for accuracy should I base load development on using 7.62 brass or 308 brass?

Do you reload?

There are exceptions*, but generally speaking anything that declares itself to be 7.62 NATO is less likely to be loaded with the same level of quality brass as loads identified as 308 Winchester “match” and made by manufacturers such as Federal and Hornady.

* I have a good quantity of Federal ammunition marked “7.62×51mm” and loaded with the 175 grain MatchKing bullet that is very precise from the rifles I’ve used it in. I don’t know anything about the quality of the brass, i.e., its consistency, but it must be good as the cartridge case is one component that matters for precision.

And although you may want to research the question yourself because I’m going on memory now, but I believe there is no difference in the chambers of 308 Winchester and 7.62 NATO (unlike, for example 223 Remington and 5.56 NATO). As I understand the difference between the two, 308 can be loaded to higher pressures than the 7.62, and some 308 should not be used in some rifles marked for the NATO round. I suspect that’s why FN affirmatively states that 308 may be safely used in the SCAR, and not because it’s better to use 7.62 for accurate results.

If you wish to develop loads for maximum precision with the rifle, I would suggest using whatever is recommended using best quality 308 Winchester brass, and whose ballistics match the calibration of your scope.

quote:

Originally posted by smschulz:
Do you reload?

Yes

Oh hey, it's the old M14 guy.

.308 and 7.62 are very close. If the rifle shoots well with .308 168, you don't need to develop a load in 7.62.. Match M118 sized chambers are for the folks who will shoot only match .308.

The differences are in the cartridge case thickness and headspace, and the 7.62 gauges are more generous.

In a typical rifle, it'll eat .308/7.62. You just don't want to put 7.62 in a match .308 chamber.

A safe 7.62 will eat a .308 No Go.

I found the Georgia Arms .308 (Nosler) Ballistic Tip 150 grain was very accurate in my SCAR. Seems happier than with 168 match.
Bought it cheap and stacked it deep.

I have no doubt if Arkansan razorbacks ever charge my home, I will be in hog heaven.

Especially if they are wearing ballistic gel body armor and phone book plates.