WV...I have found it is a matter of what the rifle "likes" ...but start with saami/factory deapths and work up. I find that a candle-smoked projectile does not work for me, so I highly polish my projectiles and 'inch' it forward using calipres and a puller until it is engraved by the lands...then back it off at least +30 thou to allow for any material/procedure irregularities/unburned powder/dirt etc and work from there. It is no good for hunting(thats me !) to safely decock a round - only to find that the barrel is completely blocked and 38gn of powder is through the tight Tikka 55 mauser action! This is the end of any days hunting when it happened once, as I had no time to rod the .17Rem out before dusk as the cleaning rod and gear were in the SUV a mile away, also pressures can be much higher seated into the lands and less powder is needed consequently-
but benchresters are good to talk to about this.
Overall lengths are given in any good loading book(I like LYMAN's 47th)and case 'trim to length data' is essential for safety too...as is a good trimmer(Redfield is mine) and a good electronic caliper(electronic is not essential - but nice).
I hope this helps a bit!
Lack of bullet concentricity is a contributing anti-accuracy factor more in my case than the above, and FLRSizing also an important factor in chambering properly only in my W30/30 ,as all the rest do 10 to 15 reloads without it - being mauser front lockers.
The Hornady Reloading Book is worthwhile to read also, as they stress safety and testing one thing at a time -in small 10% steps.
Well- WV, thats my 5c worth, welcome to the cautious and conservative world of reloading...or should that be "ammo assembly"?
BB
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