243win/115gr DTAC/RL17 Load development part 1: Pressure testing

[InkedIan]

I couldn't find any great info on this combination so I thought I would share my findings as I go...

Rifle:
Savage 10fp
Bartlein 6mm 5R 1/7.5" twist 28" chambered in standard 243win
No barrel nut
Remmy recoil lug
Xlr chassis
YHM 7.62 QD Muzzle brake
Bushnell 3.5x21x50 DMR

Load Components:
115gr Dtacs BNC
RL17 powder
Federal brass
Federal 210m primers
Loaded to touch lands at 2.289 oal off ogive

Step 1 pressure test 2 cartridges for each load with FPS and description:
39: 2877, 2915 slightly flattened primers
39.5: 2942, 2941 slightly flattened primers
40: 2981, 2977 slightly flattened primers
40.5: 3025, 2995 slightly flattened primers
41: 3060, 3063 slightly flattened primers
41.5: 3104, 3099 slightly flattened primers
42: 3134, 3135 slightly flattened primers
42.5: 3167, 3163 slightly flattened primers, slight primer cratering
43: 3206, 3202 mildly flattened primers, slight primer cratering, very slight ejector mark, slight primer gas leaking
43.5: 3243, 3225 flattened primers, mild primer cratering, very slight ejector mark, primer gas leaking
No heavy/sticky bolt for any of the loads
Thinking I will start at 41grs for accuracy testing

Pictures of brass go from left to right 39 to 43.5grs of RL17

 

[watercam]

I believe that I went with 42 gr. for the DTACs in my .243. Lapua brass/Wolf Primers/Re17. Right around 3000 to 3050 fps as I recall. Ended up using Sierra 107s with a similar charge for 3160 fps. Seemed to work better for me.