I recently put some Winchester 5.56 55gr through my bolt gun and got 4 FTF out of one 20-round box. I usually use cheaper ammo as fouling shots. I was practicing with shooting sticks for a hunt and wanted to use cheap ammo for this purpose. It may be that the primers are suited more for the ARs as I think those bolts have a stronger firing pin strike. Anyway, I won't be buying Winchester ammo - sorry Olin. I can get the PMC Bronze for less than $10 per box and have not had issues with that. BTW I am getting great accuracy from the PMC X-TAC 77gr out of my bolt rifle chambered 223 Wylde.
Thanks for sharing Cody. It looks like the Winchester primer problem may be wider in scope than what I had thought. Congratulations on your results with the 77 grain ammo. I'm looking at getting a new rifle, so maybe I can experiment with overall length. Probably a tikka T3 X
I have 3 RAP and one RA. Have you changes your trigger spring for lighter pull weight? It helped shrink all the groups on all four of mine. Its a cheap and very easy modification.