Small rifle magnum primers

Generally ive found to be just thicker cups from same brand say Rem. 6.5- 7.5 but backing off and working up is still a good idea. Accuracy definitely a difference from one brand to the next.
 
I use them with 748/760 powders in my SR brass. All I use in my Lapua 22-250AI brass.
I have never seen them alter a load, I only use them from Federal, but I have never just switched, I test both during load development. I am sure the Federal SR magnum primers are hotter, would have to check the Pressure Trace data to be sure.

Cheers.
 
I use them with 748/760 powders in my SR brass. All I use in my Lapua 22-250AI brass.
I have never seen them alter a load, I only use them from Federal, but I have never just switched, I test both during load development. I am sure the Federal SR magnum primers are hotter, would have to check the Pressure Trace data to be sure.

Cheers.
Thank you
 
I use them with 748/760 powders in my SR brass. All I use in my Lapua 22-250AI brass.
I have never seen them alter a load, I only use them from Federal, but I have never just switched, I test both during load development. I am sure the Federal SR magnum primers are hotter, would have to check the Pressure Trace data to be sure.

Cheers.
Thanks
 
I interchange them quiet often in the 6mmBR Norma. Some powders work great with the CCI BR4's and/or Rem 7 1/2's. My most consistent and accurate loads seem to come from using CCI-450 SRM's.

I saw a mention above of the Rem 6 1/2's. I read some controversy about them from a few years back. Someone was saying they were developed by Remington for low pressure cartridges, like the 22 Hornet, I think. It also went on to mention that they should not be used in .223 loads but I think they were meaning to say AR-15 loads, as the cups are thin and susceptible to slam fires in these semi's.
I have and can confirm that they behave and shoot just fine in bolt action .223 Rem's. As a matter of fact,
6 1/2's with 25.4gn of Viht N133 and 50gn VMax's is very accurate to 600yds in my Marlin X7VH.
 
Remington specifically warned against using 6.5 primers with AR's and 223 bolt guns. There 6.5 were for hornet style cases only.
 

Attachments

  • Screenshot_20210624-054902_Google.jpg
    Screenshot_20210624-054902_Google.jpg
    233.1 KB · Views: 115
I find that 6mm BR is inherently accurate with a large selection of primers/powders and bullet selections,I have at leased a dozen different combinations that are
really good.
 
I just went into my load room and pulled out a brick of 6.5 Remington primers and read the Safety warning on the box. Here is what it says: Warning do not us 6 1/2 small rifle primers in high intensity rifle cartridges such as the 17 Rem. 222 Rem, and the 223 Rem. Damage to your firearm and/or serious personal injury may result. Contact Remington Arms @ 800-243-9700 for a free catalog or visit our website: www. remington.com. Recommended primers for each cartridge are listed in the catalog ballistics tables. Looks to me like usage in high pressure cartridges is courting disaster.
 
I only use cci 450 in all small primers. AR or bolt they work great. As for extra speed, they add about 10 fps.
 
Top