OAL is 2.860" and it feeds fine from AICS mags with binder plates and without. Below is a pic of an MDT 10 round without a binder plate and how it sits.
The x47 is not a bad round but it won't do anything the Creedmoor can't. The mythical accuracy is because the name Lapua is stuck with it and it came out about 2 years before the Creedmoor so it grabbed the crowd first. Now that all sorts of brass is available for the Creedmoor, including God's brass Lapua lol, you can load whatever you want but you also have the option of a lot of very good factory ammo. The .260 can get a little more velocity than the Creedmoor, about 50fps, but for what you want more velocity isn't really needed as the x47 has less also. I never messed with the improved cartridges as I do not want to deal with fireforming.
The Creedmoor can do the accuracy you need also. A 1/2 moa steel at 1000 will come down more to a wind call honestly.
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