How far is too far,bullet seating)?

[lc284]

My understanding has been to determine at what oal is touching the lans, load some at that oal, then load some back .01,jumped), then load some crushed in .01 and see which oal shoots the best. I've heard of people crushing their bullets in as much as .02 - .03. How far is too far?

 

[fdshuster]

LC: There has to be a limit, I would imagine on the amount of bullet pull on the seated bullet, before the bullet is pushed back, deeper into the case neck, reducing powder space & raising pressures. Jamming them further into the lands will also raise pressures, so if going that route, take it slow and watch for cratered and blown primers, some will let go sooner than others, may depend on cup thickness), and hard bolt lift after firing. All signs of high pressure, and in my opinion, just not worth it. With very few exceptions, most loads produce the best/smallest groups when the bullet ogive is just lightly touching the leade. Some rounds, like my 222s demand .020' of jump. With the Berger 95 gr. VLD jammed into the lands, at a recent match, ready to fire, a call was made to 'open bolts and make the line safe'. Several of use said we had a loaded round jammed and could not take a chance of sticking the bullet in the barrel. We were told to 'fire your round, but do not reload'. Just another one of the problems when you are tightly 'jamming'. This was one of my few examples that does produce the best groups, 6BR) when 'jammed', otherwise I would not do it.

 

[jb1000br]

You can only go so far before the chamber will set back the bullet upon chambering. That length is called JAM.

JAM will usually be about 0.020' - 0.035' into the lands from what I have seen.

HTH,
JB

 

[lc284]

Thanks alot fellas, I appreciate it.