CCI 400 vs 450 for the 223

[Pathfinder76]

Does anyone have a preference? Is there enough difference between them to keep from using one over the other? Thanks.

[fatboyz]

I was using just 400's but was having some vertical stringing issues in cold weather. A benchrest shooter in BC suggested the 450's to get hotter ignition. I have had trouble sourceing 450's consistently, but have found that the Remington 7 1/2 Bench Rest primers have a little hotter spark and do the trick, plus they're more readilly available.

[sako1]

I have learned everything I know from the old man,he always used 450's so I use 450's.Kind of one of those deals..lol.I currently reload for 4 223's and have always had great results but I would not hesitate to use a 400 if I was out of stock.

[Dean2]

450 has a thicker cup and slightly hotter spark. If you are loading for an AR 450 definitely. Even loading hot for the bolt guns, I would use the 450. Normal loads, no problem using the 400s.