bullet seating

scott_r

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Can a bullet be seated out to far and cause accuracy issues?? I know it can cause feeding problems, Ive expierenced that but is there a point that it sits too far out??
What other problems arise when a bullet is seated out too far? Does it greatly affect throat erosion and pressure in the chamber??

Cheers!!
 
My own testing has shown that the closer that I seat bullets to the rifling the higher the pressure and the higher the velocity.As far as accuracy is concerned,some guns prefer the bullet closer to the rifling and some like a little more jump to the rifling.This also varies from bullet to bullet.
 
Seating

For most VLD bullets you want to get as close to the lands as you can, usually 5-10 thou. If you have a commercial chamber then you may find that with some bullets you will have too little in the case and this will result in poor runout (the bullet does not sit concentrically in the case mouth). Generally you should look at at least one bullet diameter of the bearing surface (part beyond the boat tail) to be inside the case. I have had good results with a bit less than this but have also had poor results when I was seated so long that my runout started to get really bad.

Another problem of seating too long is that you may jam the bullet into the rifling, and if you need too remove the round you may have the bullet stuck in the bbl, and your chamber full of powder. You can usually tap the bullet out of the bbl with a cleaning rod but the powder can be a pain to clean up.
 
When the bullet falls out the end of the case, that's out to far. I agree with stubblejumper that is depend on the bullet/rifle combination to find out what works best. Some like touching the lands, some may like a .050" jump. You have to test to see what works best.
You need to have enough bullet stuffed into the case to avoid run-out but not so far as the bullets jams the lands if you are soft seating.
 
I have always found when seating bullets i start at factory seating length and keep seating each cartridge 10/1000 farther out (longer) until i have trouble loading them in the gun then i go back one loading which is about 10/1000 off the lands. I have had great success with this. Buy a micrometer and keep your measurements for future loading it will give you somewhere to start if you change brands of bullets.
 
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