AR-15 load question

[adb77]

I’ve got a quick question, the loads I’ve seen for 77 gr smk are using a br4 primer. All I have are CCI 450’s. I’m loading this for a 16” 1 in 7” twist BCM AR-15. I was planning on running 24grains of varget. Given the magnum primer should I start lower?

 

[Bullspotter]

Hodgdon lists 23.7 as max load for 223 with a 77 grain SMK, Why would you start at 24?????? With a Mag primer i would start at 21.

 

[Mr Tibbs]

I’ve got a quick question, the loads I’ve seen for 77 gr smk are using a br4 primer. All I have are CCI 450’s. I’m loading this for a 16” 1 in 7” twist BCM AR-15. I was planning on running 24grains of varget. Given the magnum primer should I start lower?

Varget is a little to fast with that Magnum primer in my opinion , a little slower powder IE W748, BLC-(2), H380 would be a better choice in this application .

 

[salks]

Loading 6.5 CM with h4350 there is no real difference between br4 and 450 primers.

 

[MtnCreek]

Varget works well and 24+gr is not an uncommon charge.

Absolutely back off from 24 when starting.

 

[MALLARD]

in my experince i didn't notice a different in pressure , at least not significant, when using magnum primers comapred to br

 

[sinister]

CCI 450s and 24 of Varget is a very popular highpower competition load. Lyman 49th and 50th editions have Varget's range from 22.5 to 25.0 grains (max, compressed).

I've used Winchester Small Rifle, CCI BR-4s, Remington 7 1/2s, and just loaded a few thousand with 450s.

 

[adb77]

Thanks for all the replies, I’ll definitely start lower and work up.