bullet seating adjustment

T

trailrider121

Beginner
Mar 30, 2009
60
0
I'm currently working on a load for my 270 win. 130gr Barnes TSX using RL-17. I loaded up a few rounds and somewhat settled on a powder charge, and all seated .030" off the lands.

all 3 shot groups:

53gr RL-17 produce two holes touching and one out,making the group size .874"

53.5gr same as above- but open group to .943"

54gr. same as above- open group to 1.091"

All above loads had the same pattern of grouping two touching and one out to the left.

Now my question is should I seat them deeper or out to close the group up? Don't get me wrong, this is a good hunting load, just want to fine tune it. I read somewhere regarding bullet patterns, and how to adjust col.
 
Are the two shots that are touching fired consecutively, or is this a random pattern. If the pattern is random, then you are likely seeing a true pattern for your load. If the pattern is that two consecutive shots are touching, it may be that you are not giving enough time between shots for your barrel to cool. If there is a pressure point in the barrel channel and/or you have a thin, sporter barrel, your barrel may be "walking" as it heats up.

Because of the potential for pressure issue with the monolithic bullet, I would not advise setting it any closer to the lands. Actually, you might try moving farther out from the lands, even to as much as 0.100 inch off the lands. For monolithic bullets, freebore is not necessarily a bad thing.
 
Given this information, I would recommend seating so that you have more of a jump to the lands. At this point, you don't even need to go in 0.010 inch increments, but even 0.020 inch increments will work to tell you whether you are moving toward a tighter group of not. I believe you will find that seating between 0.050 inch and 0.100 inch from the lands will give you your best accuracy.
 
I agree with Dr Mike.

I have heard it said

"If you are getting tight groups but flyers - move away from the lands

If you are getting consistant groups but too wide a spread - move toward the lands"

Especially with the Barnes
 
I see nothing wrong with any of those loads. Try waiting 10 minutes or until the barrel is really cold for every shot and see what happens. Reason for this is you want to know where your bullet go on a cold bore shot. This is a hunting rifle not a competition rifle.
 
Seating depth Recomendations provided hear would sound right, given my experience. However, I also founs that my rifle was not free floated enough and that it would start to walk to the left as I fired successive shots. I poned up barrel channel more and that helped. Still walks though. CL
 
Thanks for the good information. I plan to make some loads using 53grs of RL-17 and seating the bullet deeper. I'm going to test using 4 shot groups this time. I'll post back my results.
 
seat them longer, try .015" off the lands, then .010 if you see no pressure signs. If you seat less than .010 off, back the charge off till you see if its gonna be overpressure.

It'll prolly work either way till you hit the node thats right but you should shoot better at longer distances if your closer.
RR
 
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