O.A.L. Query

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   I don’t bother trying to seat the 174 SMKs close to the lands on my No. 4 rifles, primarily because they must be able to be loaded into the magazine for rapid fire stages in competition.  I seat the bullets to OAL of 3.05 inches, and that is it.  I’ve checked the CBTO dimensions for the 174 SMKs, to touch the lands the bullet is about out of the case neck at that point on my Long Branch Mk 1/3 that I use for competition.  It’s a BSA 5 groove with about 8 to 10 thousand rounds thru it.  The 174 gr SMK will tolerate a LOT of jump and still be very accurate, at least to 600 yds. 
My 7.62 conversion with LB barrel is similar, tough to get a 168 SMK close to the lands.  For mid range (up to 600 yds) I load to magazine length.  For long range, I do try and get secant ogive bullets (168 and 175 TMKs) to within 0.020 to .030 inches from the lands, but they have to be single shot loaded. 

For my AR, I do seat the bullets to within 0.020 from the lands for the 600 yard prone slow fire stage.p, short line ammo is loaded to magazine length.  I generally do not recheck CBTO dimensions every time I open a new box of bullets, but do set up the bullet seater die to get the correct CBTO measurement each time I load up my 600 yd ammo.   I will also check periodically, as the throat erodes, perhaps every 1000 rounds, and reset the CBTO dimension.  