I have seen data using regular large rifle primers and magnum primers in the 300 WSM. For accuracy is ther any benifit in using a CCI 250 vs CCI 200?

I use Winchester WLR primers with all powders and bullet weights. No problems.

You generally use Magnum primers with ball powders. This is true in any case or caliber.

I usually try both & see wich give more concistant results.

My Browning A-Bolt in 300WSM likes Large Rifle primers better than Magnum primers. Velocities are more consistent shot to shot and the groups are generally tighter.

I tried several different weights from 125 up to 180 in my new Savage BVSS 300 WSM with RL 19 powder. The 125 gr I used to get the scope on. After one acope adjustment, I two holed my second and third shots at 100 yrds. I tryed some old 165 GR partitions and they sprayed out to about a 2" patern. Pattern for a three shot string was 1 1/8 using factory winchester 180 SP ammo. I have not used my chronigraph yet but 68 GR RL19 under a 180 Gr SP works real well using CCI 250 primers. This gun weighed 10 pounds before I put on the scope and has a 26" fluted stainless barrel.

If you are using stick ( not ball ) powder , try the WLR
( Win. large rifle )
I have had very good luck with them in 300WSM.

Travis F.

I've used only wlr primers in my Browning 300 WSM. Other than once when I tried a load that specified a magnum primer.

Remember that the short and fat theory is that the shorter powder column will burn easier with the big area in the bottom of the case. Also becuase the powders are in the medium burn rate, they will be more easily ignited.

Long, skinny columns of slow and ultra slow powders need a hot magnum primer to get it burning.

I have some very consistant loads, low extreme spreads and standard deviations using standard primers.