I am wanting to use 280 Rem load data for use in 7X65R, for the IMR 4350 powder. I find that the loads listed for 280 Rem are a couple of grains higher (up to 57) than for the 7X64 or 7X65R.

I have shot the 54 and 55 grains of IMR 4350 with no pressure signs, and improving accuracy and velocity. Just below that 3000 fps for a 140 grain bullet. I believe that the 55 or 56 or 57 grain load would just fill a case perfectly for the optimum loading.

My single shot K-1 Merkel rifle is designed so that it could have been ordered with a 7Rem Mag or even a 300 Win Mag chambering. This would have had the same barrel contours and same action, so I do not believe that actoin strength is limiting, at least when comparing hte 280 Rem and 7X65R chambers.

Any thoughts? Besides the obvious that I could be satisfied with 2900 fps.

I am interested in knowing how the case volumes for the 280 and 7X65 compare so that I can adjust for other bullet weights as well.

[ 04-23-2003, 02:53: Message edited by: Jameister ]

I know the 7x64 is almost the same case as the .280 and reloading data works both ways..observation shows the .280 to be the very slightly larger case...I have never tried to varify the exact difference as it was not enough to make any difference..

If you use .280 STARTING LOAD DATA, and work up half a grain at a time until you achieve either the velocity or accuracy you seek, (staying alert for obvious signs of excessive pressure as you work up, of course), you should have no problems. I doubt that there would be any problems with the strength of your rifle!!

[ 04-23-2003, 18:05: Message edited by: eldeguello ]

btt

Water capacities:
280 Rem = 95 gr
7x65R = 93 gr
7x64 = 92 gr
Pretty darn close.

I believe the 280 case is about .02" longer than the 7X64. This would explain some of the water volume difference. However, if they were both loaded to the same AOL the internal volume would be the same.

Thanks for the information. the additional volume must explain the lower pressures reached with the same loads...