I'm looking for some Remington brand small primer 6BR brass to go with the lot that I have already. Posted a Wanted already. I need a couple hundred more to fill out needs for upcoming varmint shooting. Will be resized to 22BR. If I can't find any, what would be the closest as far as base dimensions and capacity so I don't have extraction issues or need to tweak the load? My understanding is that there are some dimensional differences between the various makers. I've got a no turn chamber and the Rem 6BR brass necked down performs very well with no issues. I have some Lapua on hand but haven't put a micrometer to it, and I see Peterson brand is available and not too expensive. I'm shooting ground squirrels so my precision requirement has slightly larger tolerance than use for national BR title. Need to ship my ammo in a month so don't have long to play and the weather is not conducive to a lot of load development.