I've reloaded a lot of Berdan primed cases, and they can give spectacularly good results, but there are a lot of caveats. I could afford to shoot all factory ammo, but I like working with my hands, I'm rather tight with a buck and Berdan primers let me lower my brass cost effectively to zero. For the same .217" diameter, you will find many different heights, hardnesses and explosive strengths. DAG has brought in TulAmmo KV-24N and KV-762N, both made by Murom in Russia. The former is intended for the 7.62x39, is shorter, harder and has less explosive strength than the latter. The latter is intended for 7.62x51-class calibers, is taller, seems softer to me, and has greater explosive strength.
Batches of these two primers have been brought in before. Both are made by Murom in Russia. PMC brought in a lot of the KV-762N about 12 years ago, and I have shot them in 7.5 Swiss, FN and SA .303 brass, Albanian and early Bulgarian 7.62x54R and other calibers. They worked great in every bolt-action caliber I tried them in. Swiss 7.5x55 brass loaded with them has been used by me in 4 of the 5 Vintage Military matches I've shot in at Camp Perry, and I got a Gold medal every time. They seemed to get really flat as I approached book maximum loads and velocities, indicating to me they were pretty soft, so I was afraid of using them in loads for semi-autos without firing pin retraction springs.
I have purchased a bunch of the TulAmmo-marked KV-7.62N, also made by Murom, but have not shot any yet, still working on the PMC-marked ones.
Several years ago a batch of TulAmmo KV-24N primers were brought in, and I bought a lot of them. I tried them in Lapua Berdan 7.62x39, Yugo 7.62x39, and Swiss 7.5x55. I used 680 powder in the 7.62x39 loads, and with US jacketed bullets the Lapua shot better than the Yugo in an SKS. With the 7.5x55, I got mostly hangfires and duds even with easy to ignite 4064. Others have told me that if they opened up the flash holes on 7.5x55 brass, these primers worked fine.
As an experiment, I primed 7.5x55 cases with both primers and snapped them in a K31 rifle. The KV-762N gave two violet colored, 3 inch tongues of flame out the muzzle. The KV-24N showed just a little orange flame out the muzzle.
If you are going to use the RCBS tool to decap, buy spare pins, as you will break them. Do not use the mandrel RCBS gives you for holding cases, use a Seating die. For many calibers, the pin length is critical for successful primer removal. Try not to mash the anvil in the case: it looks like hell, but I can't see any difference on paper between cases with mashed anvils and non-mashed. Regardless of how well adjusted you have the tool, you will mash some anvils. There are some cases where primer removal will be incredibly hard: South African .303 from about 1980 used a sealant that must be epoxy, and I believe I've heard that Australian 7.62x51 is really hard.
There are a bewildering number of diameters, heights, hardnesses and strengths that have been imported and many are still made in other parts of the world. The former management of Old Western Scrounger brought in a lot of RWS primers, which were uniformly excellent. Fiocchi used to send to the US a heck of a lot of sizes. Getting someone to import them has been the problem. I wish someone would import .254" primers for most 7.62x54R, and .250" for most .303.