Troubles with Lapua Brass . . . help!
 

In my .308 especially (I also have some .223 Lapua), I have brass that the primer pocket gets so big it holds the primer loosely and even pop out at the range. This has been going on for the 2-3 years I've bought Lapua for the .308. Am I doing something wrong?
Rifle: Savage model 11. I'm loading 168 grain Barnes, 165 gr Swift or Nosler, and occationaly 175 gr Barnes. Mostly I'm loading with 42 - 44 gr RL-15 (depending on bullet) which is well within loading data specs. I am using Winchester LRP's. I've had guys look at my spent casings and there is no indication of flattened primers from high pressure.
So........ I don't want to waste my money on Lapua any more. I'm only getting 3 - 5 reloads out of them before some (not all) pockets get loose. I just reloaded some today and all of them went in "too easy". Almost no resistance at all.
So, what the you know what? And what other brand of brass would I go to? Anyone try Swift?
Also, I clean with the Frankford Arsenal Platinum Series Rotary Case Tumbler, and I use the RCBS Priming Tool.