Magnum primers - what effect on standard rounds?

[Jeffpatton00]

I was able to purchase some CCI 450 SR magnum primers since my preferred SR benchrest primers aren't available. My question is, for 223 Rem or 224 Valkyrie, what effect will magnum primers likely have? I'm not concerned about high precision for the 223 Rem, those are more for taking buddies or new shooters to the range, but I'm very interested in the effect the magnum primers would have on the 224V rounds. I'm using Varget and 69 - 77 SMK HPBT bullets for 223 Rem, and VV N140 w/ SMK 90 gr HPBT for the 224V. In case this has any connection to primers, the 224V has a 30" Bartlein barrel with 5R progressive twist to 6.5. thx

 

[Mikecr]

There is no predicting this. You just start over with load development.

 

[MagnumManiac]

I run magnum primers in my 222, it made a good load great. Just a simple primer change can make all the difference.
Give it a try and work up, you may be pleasantly surprised.

Cheers.

 

[P7M13]

Is the Valk a bolt gun or semi auto?

 

[Hugnot]

I use nothing but small rifle magnum primers in my .223, .20P, .204R & 6.5X47Lapua, preferring them over the standard primers because the magnum primer cups are thicker by .005 or slightly more depending on primer comparison. I have had CCI 400 primer dimples extruded into the bolt face firing pin hole and this is with a tight fit between firing pin and bolt face hole. CCI BR4 (bench rest types) primers have the same cup thickness as 450's & 7 1/2's - .025". My feeling is that thin cup small rifle primers are best suited for low pressure use.

 

[lancetkenyon]

Natchez has GM205MAR primers in stock as we speak...

 

[Jeffpatton00]

Natchez has GM205MAR primers in stock as we speak...

Thanks! I got some.

 

[Hugnot]

GM205MAR - I have some of these & use them with complete satisfaction in my bolt guns. But, just under $110 including shipping

 

[243winxb]

I interchange CCI 400 & CCI 450 in 223, does not seem to make a pressure difference. The 400s flow more into the firing pin hole. Thinner.

 

[imyourhuckleberry]

The Sierra manual states you should reduce your loads by 5%.

 

[Zen Archery]

If you load hot back off a few gr. If standard test it and see. I've noticed with all my hot loads I had to reduce between 3-5gr.

 

[CBH Australia]

All very interesting,
I keep some for my Magnums.
I knew and old guy once who used Magnum primers in other loads.
Watching with interest.

 

[MagnumManiac]

I use magnum primers in standard rounds and standard primers in magnum loads…guess I'm a bit strange.

Cheers.

 

[RYEWSKY25284]

I was able to purchase some CCI 450 SR magnum primers since my preferred SR benchrest primers aren't available. My question is, for 223 Rem or 224 Valkyrie, what effect will magnum primers likely have? I'm not concerned about high precision for the 223 Rem, those are more for taking buddies or new shooters to the range, but I'm very interested in the effect the magnum primers would have on the 224V rounds. I'm using Varget and 69 - 77 SMK HPBT bullets for 223 Rem, and VV N140 w/ SMK 90 gr HPBT for the 224V. In case this has any connection to primers, the 224V has a 30" Bartlein barrel with 5R progressive twist to 6.5. thx

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