Thread: Sticky ammo

I took my recently acquired Rem mod 7 in 308 to the range last week as I wanted to sight in with new ammo. The rifle was sighted in at 50 yrds by myself, with Hornady 150 sst when I got it, but wanted to step up to something more suited to big reds.
The new ammo is 165 gr Australian outback, which I thought I would try as it is factory loaded with Sierra gamekings, which I like.
I only put five down the range, and every round stuck in the chamber after firing, meaning I had to give the bolt a whack to release the spent cartridge.
The rifle cycled Hornady just fine, so I am guessing the ammo is at fault here and not the rifle.
Any thoughts please?