GM210M vs Rem 9-1/2M for 140gn AH 280AI?

[PersiMan]

I am still piecing together parts to try 140 gn Absolute Hammer in my 280AI 1:9 22". I found TWO CANS of IMR 4451 last week. That was an exciting moment. The only rifle powder I've seen this spring. It seems like most are recommending magnum primers, and today I finally found Remington 9-1/2M. People don't talk about them much. I also have the regular large rifle primers Federal Gold Match 210M , which is what I've always used in 280AI.
Would you start working on loads with either of these primers (and, which one?), or wait for more famous magnum primers like Fed 215 M?
I really want to get going and make sure I have a good shooter for fall. Three other copper bullets in stock if AH doesn't work; and could go back to 162 ELD-X if none of the coppers work. But I don't want to waste my time if men feel that the correct magnum primer is a prerequisite.
Thanks for all replies.
PS: Today I found a lone can of H 100V. That's the only option I have in a slower burn rate.

 

[Ckleeves]

Doing load development in a buddies 280 ai the winning primer was 210m's on SD and groups. IMO people way overthink primers. Sure, a primer change can clean up some bad extreme spreads and slightly shrink groups but I have never seen a change preform any miracles. Load what you got. YMMV.

 

[GLTaylor]

You're good!
Go to the Absolute Hammer Load Data thread, post #2
There is a data sheet there for the Absolutes.
Many feel magnum primers give the Absolutes a little "head start" , but many still get good results with regular primers.
I suggest you start with the H100V. However, the 4451 will probably do well too.
Work up loads with whatever primer you have most of. Rems are fine. When you get a load you can substitute primers to see if one outperforms the other.
Many also find neck crimping with a light crimp gives these slippery bullets a better start.
Good luck and keep us posted.