Quoted:
CCI/Speer Technical Services says:
The CCI 400 primer does have a thinner cup bottom than CCI 450, #41 or
BR4 primers.
The appropriate primer for an AR15 platform is the CCI #41 primer, which
helps to prevent slamfires. With this primer there is more 'distance'
between the tip of the anvil and the bottom of the cup.
Linda Olin
CCI/Speer Technical Services
2299 Snake River Ave.
Lewiston, ID 83501
You will have to decide for yourself on this one - but I would prefer to stick with the thicker cupped 450, BR4 or the mil-spec #41 myself if possible for a greater safety margin.
WOW.......someone actually asked CCI.
That is impressive.
______________________________
I wonder how CCI would have responded if they were asked?
There aren't #41s (or #450) primers to be found. So, can I use #400 primers to reload for .223 Rem/5.56?
I suspect that they may have given you the
GREEN LIGHT.
That being said...........I've used CCI #400 (standard small primers) with .223 Rem/5.56 loads.
My SPEER manual uses them (CCI #400) along with #450 sm. mag primers. The difference in the recommendations is mostly based on powder type (for that caliber).
The stuff about "slam fires"...............well, it's also appropriate to note that proper seating depth is important as well as the condition of your firearm, etc.........
CCI in their own website states (about the #41)............
*Effective slam-fire prevention requires more than special primers. Headspace, chamber condition, firing pin shape and protrusion, bolt velocity, cartridge case condition, and other factors can affect slam-fire potential.
I suspect...........that CCI responded the way they did..........in order to PROMOTE if not to BUILD and CREATE demand. Besides, there are customer loyalty issues at stake.
Aloha, Mark
PS..........remember when we didn't have "military spec" primers offered by CCI?
Prior to that.......it must have been "slam fire city" at ranges all across the country. LOL.