I have attached my targets from my load development efforts to produce a 2830 fps load with 150 gr ABLR for my Rem 700 in 270 Win.
The first page shows my first attempt with H4831sc. I never could approach the velocities I wanted.
The second page shows my first attempt with IMR 7828ssc at 27 grs with a COAL of 3.340". The velocities were higher than I wanted.
The third page shows my attempts with RL 22 and another try with the IMR 7828ssc. The RL 22 looked very promising until I shot the IMR 7828ssc. I used 56.5 grs. of IMR 7828ssc with a COAL of 3.380 (about .060" off the lands). This really impressed me.
The top of the fourth page shows my attempt to reproduce the above results with the IMR 7828ssc. This was a different reloading session with a new batch of primers and a very slight adjustment in head space. I was able to reproduce the previous results.
The bottom of the fourth page shows making a COAL increase to 3.400". No real change. I may or may not have pulled the third shot.
The fifth page shows making a COAL decrease to 3.364". The group is opening up.
So it looks like the load for my rifle for this hunting season is:
150 gr. ABLR
New Norma Brass with head space measured at -.0005"
WLR primers
56.5 gr. of IMR 7828ssc
C.O.A.L. of 3.380"
I guess I can live with the extra 20 - 40 FPS.
Should I be at all concerned with velocity spreads of 40 - 50 fps?
Is this as good as I can reasonably expect? I don't think I can shoot any better this this anyway. Is it worth trying more load development (RL22) next year?
The first page shows my first attempt with H4831sc. I never could approach the velocities I wanted.
The second page shows my first attempt with IMR 7828ssc at 27 grs with a COAL of 3.340". The velocities were higher than I wanted.
The third page shows my attempts with RL 22 and another try with the IMR 7828ssc. The RL 22 looked very promising until I shot the IMR 7828ssc. I used 56.5 grs. of IMR 7828ssc with a COAL of 3.380 (about .060" off the lands). This really impressed me.
The top of the fourth page shows my attempt to reproduce the above results with the IMR 7828ssc. This was a different reloading session with a new batch of primers and a very slight adjustment in head space. I was able to reproduce the previous results.
The bottom of the fourth page shows making a COAL increase to 3.400". No real change. I may or may not have pulled the third shot.
The fifth page shows making a COAL decrease to 3.364". The group is opening up.
So it looks like the load for my rifle for this hunting season is:
150 gr. ABLR
New Norma Brass with head space measured at -.0005"
WLR primers
56.5 gr. of IMR 7828ssc
C.O.A.L. of 3.380"
I guess I can live with the extra 20 - 40 FPS.
Should I be at all concerned with velocity spreads of 40 - 50 fps?
Is this as good as I can reasonably expect? I don't think I can shoot any better this this anyway. Is it worth trying more load development (RL22) next year?