quote:

Originally posted by NONAGONAGIN:
Weight sorting after nose uniforming and ogive measuring work best for me along with the other BR tuning tricks system and cases. Ogives can be off by several thou...usually 2-5 bullets per box and weights up to 15 gr. I don't measure bullet OAL's anymore, just uniformly trim noses to some arbitrary OAL, usually a few thou shorter than the shortest measured bullet...the new tools make it MUCH easier than in the old days.

Try it first before you laugh. Weight sort, nose trim, measure ogives and get the bullets as uniform as you can in separate piles and fire a group...THEN...take a few with mixed longer/shorter ogives and fire them....if your rifle and you are up to it you will see the variation in group size.

If you want to really see what variation is ogive measure a full box of bullets...NOT CUSTOM or CNC bullets...they are usually exceedingly uniform in all dimensions....use available factory brands. I've measured 3 different ogive measurements in one box of "Match" bullets...normally there are only one or two and depending on when/where the bullets were boxed during the bullet making run I've gotten only one sometimes and 10-11 at other times. These bullets come at a point where something in the building components has changed and the quality control has gone out of spec.

AS long as I shoot the bullets by ogive measurement groups the dispersion isn't anything significant...I get bugholes for ALL bullet groups.

Bullet weights can be variable due to differences in the metal composition or tiny voids which can set up an instability that causes the bullet to yaw.

Not many except target shooters care to go through this much troubles and this works even in the largest calibers, but who wants to go through all that pain to gain a bit of accuracy when 1 minute of animal is all that is needed.

Primers are a big source of variation in accuracy and group size. For all my rifles that have been tuned for max accuracy I only use BR type primers and whatever brand shows the highest potential...PER RIFLE and caliber...BR primers USUALLY give the highest accuracy, but NOT always What brand works best is rifle dependent...DON'T ask me why. A bad primer can cause a flier just as well as any of the other things.

One major problem with trying to understand fliers is once the round is fired ALL the components are destroyed/changed in some way and you can't dissect a hole ion the paper. It could have been the primer, the case, the bullet, the powder amount, the shooter or a bug got in the way...it also can be the barrel vibration node just slightly off or the bag settled at the wrong time...or the Devil was just messing with you...hard to diagnose.

A case can be the problem but because any imperfections in the case walls is difficult to diagnose unless you mark the case as to position and shoot it in that position every time. If you keep getting a flier hitting rear there same point every time, you might just eliminate that case for one group to see if you get a hit at the same point...if not you have you culprit.

I could buy a very expensive, fancy-shmancy double rifle for the cost of components and time I've burned up to find just 10 cases that shot into one hole, consistently. Things have changed for the better in today's world...not as hard to find that consistent "bughole" accuracy with today's components, rifles and reloading tools...plus all the information on the net.

LUCK

quote:

Originally posted by Instructor:
Not a bench rest shooter striving for the smallest possible group. Shoot primarily Long Range NRA type matches and goal is to shoot as many X's and 10's as possible in prone w/sling and micrometer sight system, no optics. Use exclusively Lapua brass, SMK bullets, Fed. 210M primers and with 308 primarily IMR 4064 powder. Range of targets from 600 to 1000yds. Bullet selection is either SMK 155 Palma or SMK 190's, depends on the wind conditions during match day. As for fliers, believe in my case they are brought about by me, not the loads or the rifle, just me and not braking the shot as I should. You will know if the shot is a good one or bad one at the moment you break the trigger, if not you have not shot enough and unable to decipher the wind conditions and make correct adjustment on the sight. The absolute finest reloads possible will not show up on the target face without skilled hands holding the rifle. Trim brass if needed, clean primer pocket, deburr case mouth out and in, seat bullet to suit your chamber/throat, accurate powder measurement, and the rest is up to the trigger puller.