Can't imagine getting any better than the CCI BR2 primers, though am surprised that you can find them. Am shooting CCI 200 in mine and they work just fine with 56-59gr of 2F Goex or 56-58gr of 1 1/2F Swiss. Every rifle is different, so you will have to work out the seating depth by results on paper.

Have found most any LR primers to work well. I use CCI 200s as they were readily available last year. Have also used Rem 9 1/2s with good results. Groups of 1 - 1 1/2" are just fine for silhouette if that is what you are after and can do the same MOA at 500m. I'm shooting a 355gr bullet in 20-1 at 500m and it works well. But, so do my 340gr & 325gr bullets.

Think I've finally figured out how to shoot a long-range BPCR rifle. Shot the best I've to-date this weekend with a tie for my personal best on Sat and a new high on Sun. My loads are 56gr of Swiss 1 1/2F pushing the BACo 325gr 'Money' bullet for chickens (200m), 57gr with the same bullet for pigs (300m), 57gr pushing a Brooks 340gr bullet for turkeys (385m) and 58gr pushing a BACo 355gr bullet for rams (500m). My experience is that the 38-56 is pretty insensitive to both primer selection and powder. I usually load the same amount of Goex and it shoots about the same.  I've used 215M primers to good effect. Same with the 210. Won some Olde Eynsford this weekend, so will give that a try at some point. Have shot as high as 267 in mid-range. Think it is an accurate cartridge, but not so easy to find the 'magic' mix. Especially if shooting for group size. Mine usually shoots in the high-90s at 200yd in our mid-range matches.

In my rifle going above 60gr tends to open the group with both Goex and Swiss. With the 325gr bullet 58gr of Goex is pushing the bullet at 1385fps and the same load of Swiss ups that to 1425fps. I've forgotten the spread, but the Goex was under 20 and the Swiss was a single-digit.

Am also using as many as four (4) 0.060" wads to space my fixed ammo out to get the first driving band into the rifling. With my most accurate loads I am using a 0.060" fiber wad on the powder, followed by 2x 0.060" plastic wads, a 0.030" plastic wad and a 0.022" card wad or newspaper wad (to insure nothing sticks to the base of the bullet). With the 355gr bullet don't use the 0.030" wad. This combination gives some amount of compression on the powder (more with Goex than Swiss). Not overloading the case, getting some compression and spacing the bullet forward into the rifling were the three keys to getting my rifle to shoot well. Now it is up to the nut behind the trigger (me).

Thanks guys, Today I tried three loads with different primers. Target # 1 was with 62gr PP Wano and using Fed GM215M primers, Average speed was 1332 fps, spread was 100 fps. Group size was 2.070"
Target # 2  was also 62 gr with the CCI 200 LR for an average of 1359 fps and a spread of 25 fps. group size was .590"
Target # 3 was 60 gr of PP Wano using the CCI BR 2 average speed was 1353 fps with a spread of 25 fps, group size was 2.375 with four shots in 1.195".
All targets were with the bullet breech seated approximately .075 ahead of the case. In all cases the powder was topped with two .060" LDPE wads finger seated.
I will re visit the target 2 load again to verify the result, perhaps it was something I ate for breakfast.
Mike.

I'm still using my supply of CCI 200 primers. Always work well for mine.