[s.forktraveler]

i have used a "dummy" round to find max over all round length for many years
for my 220 swift & 243 -- my question is what would be considered optimum bullet jump -- i am considering .002 -- is this to fine ? or should i start at say
.006 and work down watching group results

[Scimmia]

It's going to be different for every rifle. 006 is pretty tight, don't expect your best accuracy to be between the numbers you posted. It could very well be up around .100 or more.

[parker51]

i have used a "dummy" round to find max over all round length for many years
for my 220 swift & 243 -- my question is what would be considered optimum bullet jump -- i am considering .002 -- is this to fine ? or should i start at say
.006 and work down watching group results
Some reloaders claim that right up against the lands. I personally use .010 as a starting point for most of my rifles but some it is impossible to use this number as the bullets would be just about out of the case with some bullets. It just depends on how deep the throat is on your rifle and also depends on whether you intend to hunt with it or just for shooting targets. I try to have at least the width of the bullet seated inside the neck of the case. Hope this helps.

[Epoxyoyo]

I've loaded for 2 different 270's, 2 different 7mm-08's and a 30-06 and all 5 rifles liked .020 off the lands. You may want to start there. Then move a few in to .010 and a few the other direction to .030 to see which gets better or worse. Once you know that then you can make small adjustments till you get it dialed in.

[gamestalker]

For most of my bolt guns I seat up to the lands, touching. But, anyone doing this must work the load up at that OAL or pressures can spike without warning. But if I have a particular load that doesn't perform well touching, I back off at least .010" off the lands to account for inconsistencies in olgive from one bullet to the next. Just make sure you have given yourself enough magin to prevent unintended contact with the lands.
GS

[Walkalong]

.002 is not only very tight, but not repeatable. Some will be into the lands, while others are farther off than .002.

For most of my bolt guns I seat up to the lands, touching. But, anyone doing this must work the load up at that OAL or pressures can spike without warning. But if I have a particular load that doesn't perform well touching, I back off at least .010" off the lands to account for inconsistencies in olgive from one bullet to the next. Just make sure you have given yourself enough magin to prevent unintended contact with the lands.
GS Good advise.