The 25 sst...up and running

So I finally got a couple days off to work with this new 25 some. Looking like I'll probably settle in around 60.6 of n565 for now. It's just a hair over 3200fps out of my 24" bbl. seems I hit pressure a grain or so before some guys but all in all I'm very happy with it. Also loaded 3 of the 128 hammers just to see if they'd make round holes at 100 with the 7.25 twist and it looks good so far! Broke the buckle on my magnetospeed so I don't know how fast they were but with the same 60.6 I was shooting the blackjacks, I had a pretty prominent ejector mark and too much pressure. Gotta get out and find a couple good bucks for the end of the month if I can ever get over this nasty head cold!
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Also, I've gone rounds with my curtis 3 round mags. They wouldn't feed the sst very well and I managed to mill them out enough to get them to feed properly but they also wouldn't lock in with the bolt closed. Not enough depth. Curtis offered multiple times to take a look at them for me but I opted to go at it myself so I can't fault them there. Didn't feel like shimming the bottom metal down was the proper solution because I didn't want to have any less contact between the bolt nose and the case head so I pulled the plastic follower and made my own out of 18 gauge. Got them working good but I don't think I'd recommend them for Rich's cases in the future. I also picked up a set of accurate wsm mags that I'll most likely use instead. Just figured I'd pass this info along.
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Also, I've gone rounds with my curtis 3 round mags. They wouldn't feed the sst very well and I managed to mill them out enough to get them to feed properly but they also wouldn't lock in with the bolt closed. Not enough depth. Curtis offered multiple times to take a look at them for me but I opted to go at it myself so I can't fault them there. Didn't feel like shimming the bottom metal down was the proper solution because I didn't want to have any less contact between the bolt nose and the case head so I pulled the plastic follower and made my own out of 18 gauge. Got them working good but I don't think I'd recommend them for Rich's cases in the future. I also picked up a set of accurate wsm mags that I'll most likely use instead. Just figured I'd pass this info along.
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What is the diameter of the 25 SST at the shoulder ? Does anyone have a dimensional drawing or specs. of the 25 SST. It would seem that it would be a better cartridge for my needs than my 6.5 Creedmoor. It certainly would shoot much flatter and retain more energy. I can't seem to find any dimensional data on the SST's anymore, and I thought I had saved those photos and dimensions.
 
I see a few of you guys have ran pressure tests with Retumbo but I was curious if anyone is using it as a go to in this case? I dabbled in it a little and got about the same speeds as I'm getting with n565 but the small sample set I did before I had to go back to work had high es and didn't group well. Haven't played with seating depth yet but 565 is shooting pretty good.
 
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