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Old 05-14-2018, 3:59 AM
kcstott kcstott is offline
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Quote:
Originally Posted by idlplumb View Post
Some good advice here guys. Iím noticing that there are a few steps I could skip or consolidate and maybe some new equipment I could buy to help speed things up.

Iím not competing, but I would like to know that group size is my fault and not something Iím doing wrong with the loads. Thatís why I donít mind spending the extra time with brass prep.


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Extra brass prep will not show up till you are competing in international benchrest and shooting high tens to low hundreds. (i.e. groups that range from .080" to .130")

With crap brass and good bullets and attention to powder charge you can get groups in the sub moa range quite easily.

This is not scientific stats but i'd guess about 85% of your rifles accuracy outside of the barrel is the quality of the bullet and the consistency in the powder charge. Brass becomes and issue with inconsistent powder capacity creating inconsistent pressures and therefor inconsistent velocities. Neck tension becomes an issue as well and this can be solved by using a bushing die for the most part but with slight inconsistency in neck wall thicknesses, this is where neck turning comes in to play. Neck turning creates uniform wall thicknesses and therefor uniform neck tension and it also reduces bullet runout assuming the ID was concentric to the axis of the case.

That said there is also the point of sorting bullets by weight, then buy bearing surface, meplat trimming and tipping for higher BC's, weight sorting of brass, benchrest primers, using and arbor press and benchrest dies. the rabbit hole runs as deep as you like. but for 99% of us it comes down to quality brass with a quality bullet and a good amount of attention to detail. Match grade ammo can be made on non match loading gear. it just depends on the match you are shooting.

I see more vertical stringing from the temp rise throughout the day and guys leaving their ammo boxes in the sun then anything else, Also chambering a round in a hot chamber, don't do it till you are ready to fire. that heat in the chamber will soak in the brass and warm your powder causing a higher velocity. I run a sled in my f class matches, i set a round on the sled bolt open. get pretty close to lined up natural point of aim and all that rebuild my position as needed. then chamber the round make my final adjustment and press the trigger at my natural respiratory pause.
If i'm lucky and didn't pull the shot, read the wind right, I should be in the 10 ring. but I'm working on that I shout a 9.2 point average right now.
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