I found a good deal on some Federal Fusion 62gr, but I have only ever used the MSR version, and this is the standard fusion.  Will it work fine in my 10.3" SBR and all my other AR's, or do I need to stick with the MSR version?

A member did a test on this site between the two and they're with 45-50 fps of each other I believe. The casings are different colors though.

Eta: Using 14.5 Noveske Barrel
Standard: 2610 fps
MSR: 2681 fps

Honestly my biggest concern is the softer primer in the standard version vs. the MSR version.  Is this something I should worry about on an AR?

I have never seen it be an issue.

I know you're asking about the 556 stuff, I chrono'd the 308 stuff and there was a definite difference in a 20" barrel. Fusion runs pretty hot as it is, even the standard stuff. The standard 308 was about 2790 and the MSR was about 2910. I suppose about a 5% difference. You can certainly feel the difference when firing it.



For comparison American Whitetail was about 2724.



Regarding primers, I've shot a lot of FF standard through both 308 and 708 ARs and never had an issue. I suppose there's a first time for everything...



-Stooxie

i only wish it was more accurate for me.of all the specialty ammo i've shot,  its the least accurate.

those rounds being, 55gr GMX, Mk318,  speer 62gr gold dot, TAP T2, TAP FDP, IMI razor, M193, IMI M193, wolf gold