There's some data in I think in the Speer manual on using magnum primers in .223.... They are mainly used with ball powders that are harder to light off than stick powders.... As per normal you will want to back the charge off and work up with them... I don't see any reason to use them with stick powder unless you just want to... The thicker cups can prevent slam fires in automatics but I just use normal CCI S/R primers in my AR loads and have never had the problem , fortunately mine don't seem to hit the primers , my SKSs are a different story , it hits them scary bad.... You using a bolt gun will not have these problems....I am asking about using them in a bolt gun
Lake City uses magnum primers with all their 5.56 ammunition.
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CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS
Primer Info & Chart + Milspec Primers for Semi-Autos & Other Primer Applications
http://www.sksboards.com/smf/index.php?topic=56422.0
Small Rifle Standard
CCI 400 -thin .020" cup, not recommended for AR15 use by CCI/Speer. Good for .22 Hornet, .30 Carbine. See Note 1 at the bottom of the page
Primers recommended for use in .223 Rem/5.56 semiautomatic rifle loads:
CCI #41, 450, BR4
Federal 205, 205M
Remington 7 1/2 BR
Winchester WSR
Wolf/Tula SRM
Wolf/Tula SR223
NOTE 1: According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably.
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The CCI #41 and CCI #34 are both magnum type primers One large difference between, for example a CCI #41 small rifle primer and a CCI 450 small rifle magnum primer is the CCI #41 also has the anvil at a slightly different angle in addition to the slightly thicker cup.So Ed if I am reading the chart correctly they are using no 41 primers..? If so then the 41s are a magnum primer..? I have always thought the no 41s were just the 450 primers repackaged...
Good info , thank you RonThe CCI #41 and CCI #34 are both magnum type primers One large difference between, for example a CCI #41 small rifle primer and a CCI 450 small rifle magnum primer is the CCI #41 also has the anvil at a slightly different angle in addition to the slightly thicker cup.
Question:
Regarding CCI #34 primers. The question has come up or it has been stated that CCI #34 primers are the same thing as CCI 250 Large Rifle Magnum primers. While I know the CCI #34 is a magnum primer I believe it is not the same as other large rifle magnum primers in that it has further reduced sensitivity. Would that be correct and is the priming mix different than standard large rifle magnum primers.
Answer:
Ron, here are the differences in the 2 primers. So the anvil angle change is the difference, this keeps the free floating firing pins from causing slam-fires in AR style platforms. This does make it so that a light strike will have a less of a change of going off.
CCI-250............................ Magnum primer, Mag primer mix, thick cup, standard anvil.
#34/7.62MM................... Mil. Spec. primer, thick cup, magnum primer charge, angle of anvil change.
Justin M./Technical Service Rep.
2299 Snake River Ave.
Lewiston, ID 83501
Alliant/Blazer/CCI/Speer
(800)379-1732
The replay mentions the #34 LR but also holds true for the #41 SR. CCI is always happy to address any questions you toss at them.
Ron
So Ed if I am reading the chart correctly they are using no 41 primers..? If so then the 41s are a magnum primer..? I have always thought the no 41s were just the 450 primers repackaged...
Is there any advantage using magnum primers when reloading 223's with Varget or Reloader 15 ?