bullet seating accuracy

[fireworks]

Well I managed to dial it in. Funny find though, the lands on the berger and on the accubond LR are only 1000th apart. With the bergers, good results 0.020 ( COAL 3.443) off w/ 56.5 gr. 7828ssc and remington mag. primers. (best I could find) Three shots inside a dime at 100 yds. mean FPS 2912.
The accubond LR seated the same (COAL 3.443) w/ 56.0 gr. were covered with a quarter but the wind was up a little by then so I factor that in. Ironically, mean FPS??? 2912. Wierd.

My next question is: Do the federal mag. 210 or 215 primers really make a good 100FPS difference? Very hard to find. Again I'm using remington mag. large rifle primers. Would using fed. 215 tip the 3000 FPS??

Obviously I've read alot of posts...Any B.S. on that theory?

 

[Mikecr]

Changing primers can have a significant affect on velocity, and it will wreck any tune to this point.
But I don't think there is any predictability to MV going up or down with primer changes.

Also, if anything, Rem primers are among the hottest out there.

 

[Mikecr]

But the bullets don't really exert back pressure from engraving forces until the bullet actually hits the beginning of the lands

I would say what you're describing is the difference between 'touch' and 'jam'.
While measuring to determine MaxOAL, like with an R-P tool, you're not exerting so much force on a bullet to reach consistent jam. Just touching,, and this is your consistent reference w/resp to land contact.