- Oct 29, 2018
On the 3rd reloading with no issues with brass.
No. 3050 fps with a 140 grain TTSX out of a 22" barrel with 7x57 AI. I could probably go up to 3100 without any pressure signs, but accuracy is excellent at 3050. Getting 2650 with 250 grain round nose Hornady's with the 35. 2400 FPS with 250 & 286's in the 9.3. Both the 35 & 9.3 are stout in recoil.
3rd total, or 3rd after the shoulders were fully formed?
Norma brass will start getting tight and showing ejector marks before Federal or S&B primers start getting flat, so you may or may not have as much room to increase that load as you think.
You’re 100fps behind a standard 280Rem using, Nosler datawith your current load, so I would highly doubt that you could knock at the door of a .280AI.
7-08 looses 21fps/“ so load data suggests that if you stay within pressure specs you might just barely eek out 2500fps. Pushing pressure in Lapua brass or using coated bullets could help get you there. A 7x57 or 7-08AI could both give you just enough to hit 2500fps without being hard on brass and without having to find the exact perfect powder. Neither is a substantial improvement(in terms of velocity) over a standard 7-08.
280Rem should lose about 27fps/“ so using load data says you’ll top out around 2650fps. That’s a substantial improvement over a 7-08. A 7x57AI would get close, but likely not equal if pressures were equal.
A 280AI loses about 29fps/“ so that would give you 2750fps, 2800fps with the top powder using Nosler data.
All of the above are assuming an 18” barrel, staying within book max, and using a 168gr bullet.