Looking at a 308 Palma rifle. I understand that using small rifle primers may cause minor issues when ambient temperatures are low. Would small rifle magnum primers help to mitigate the issue?
Ignorant and trying to learn……

I have experienced no issues shooting in 37 - 95 degree temps here in Phoenix. This is with CCI450s, BR4s, and Remington 7 1/2s. I sometimes store the ammo in a small cooler ( no ice) to buffer the temp swings as the match progresses.

Hope you buy the rifle and give Palma shooting a try. Lots of fun and very little "equipment race".

The opposite of cold weather, but the CCI 450s in Lapua brass shot fine with 155.5 Bergers, Irons and sling this morning at 1000 yards here in Phoenix. About 90 degrees at 7:30AM. Screenshots from Silver Mountain E Target system.

Well, I didn’t win the Palma rifle, so I’m thinking of shooting the small rifle primers in my plain Jane target 308.
I think it might be worth a try…..
What is the average barrel length most Palma shooters use?

Usually 30 to 32 inches. That helps with the velocity and puts the front sight at a distance that correlates to 1/4" MOA clicks on the rear sight which gets a workout at 1000 yards. Not really possible to hold off for windage like with a scope.