trajectory, small powder differential, and accuracy with 708

[Doctor]

i shoot silohuette. My Ram loads are 169 grain barnes with 41.5 gr of 4350

the extruded powder in my rcbs powder dump does not meter regularly and i have not been weighing each round. The powder charge can vary by half grain or so. The real experienced shooters ( i am not) were zeroing my rifle and they figured the varied weight of powder would not allow it to zero at the 500m mark on a regular basis. What kind of error am i introducing by being off a half grain or so at 500meters?

[Guy Neill]

The best way to tell is to load a test series. Weigh each charge at your desired load batch, and 0.5 grains on either side and shoot them for group and impact point comparison.

I expect you will see minor variation, but not such that you cannot zero the gun. For that I would expect bedding or other gun problem. As a check to this, if you have access to another rifle, shoot it as well with your test loads and see how they compare to yours.

Guy

[Doctor]

Thank you

[dauntedfuture]

I suspect that 50 FPS +/-, or a 100 FPS ES would be about 4" or a little less then 1 MOA at 500 yds. Past 500 yds, things really start to open up with ES in reloads, 100 FPS at 1000 yds with a is 24" or more I think. This is provided your rifle does not have harmonic issues which can contribute to elevation problems. You can get away with more with a .308 then you can with a .223, but I weigh my 300yd charges for NRA HP in .223.

H4350 is quite slow for .308. What Barnes bullets are you using? If they are barnes match bullets and wthey shoot well you are good. I would not waste any of the high dollar barnes bonded or solid bullets on rams. If it was me, I would look at Varget, RL15 or H4895 or another powder in that burn rate, about 40-42g, weigh your powder and look for a 168-175g BTHP match bullet.

[Doctor]

thanks