Ladder test with only a Chronograph

Chronometers are necessary for celestial navigation to note the exact time the angle up from the horizon a heavenly body is. The earth surface on the equator at sea level moves about 1518 feet per second.
 
So I think the reality is there is more than one tunable dynamic involved, which is why these different approaches all work to different degrees with different rifles. The ideal will get all the dynamic factors optimized at the same time
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everything is interconnected. Powder charge, seating depth, primer brand/type. Change one and you change the velocity and the accuracy/precision. Changing shoulder pressure, body position or a inconsistent hold can change things also. Benchresters will argue that neck tension plays into it but for my skill equipment level I just use .003 for everything and call it good
 

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hounddawg, have you ever measured the force in pounds it takes to pull seated bullets from case necks for a .002" interference fit compared to a .001" interference fit?

Interference fit is the difference between bullet diameter and resized case neck inside diameter.
 
hounddawg, have you ever measured the force in pounds it takes to pull seated bullets from case necks for a .002" interference fit compared to a .001" interference fit?

Interference fit is the difference between bullet diameter and resized case neck inside diameter.
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why would I care how many pounds it took to pull a bullet from a loaded case ? It's how it shoots that matters. I did a few range tests using various cartridges and bullets and found .003 performed the best in every test and does not damage the jacket. Also experimented with various lubes, inline dies and number of other "tricks" and saw no differences on paper
 
hounddawg said:
why would I care how many pounds it took to pull a bullet from a loaded case ?
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Because that's the only meaningful way to assess how tight case necks grip bullets. Neck tension is a force, not a dimension. It's an industry standard. Interference fit dimensions alone have too many related variables.

Depending on case neck metal and dimensional properties in the grip area, the same amount of the interference fit won't grip the bullets uniformly and the pull forces across all won't be the same. Muzzle velocity will be higher the more grip on the bullet is causing more force to pull the bullet.
 
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Seating tension

You two reminded me of the tension experienced while seating a bullet. Sometimes I've felt the bullet seat with a little more tension than the rest. I never marked that case or made a note of it, but always thought to myself that this round throw off an otherwise nice group. Do you discard these rounds when they are part of a test load or match load set?
 
burbank_jung said:
You two reminded me of the tension experienced while seating a bullet. Sometimes I've felt the bullet seat with a little more tension than the rest. I never marked that case or made a note of it, but always thought to myself that this round throw off an otherwise nice group. Do you discard these rounds when they are part of a test load or match load set?
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Keep the easy seating ones separate and shoot them together at another time.
 
Sometimes I've felt the bullet seat with a little more tension than the rest. I never marked that case or made a note of it, but always thought to myself that this round throw off an otherwise nice group
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next time you get one of those, paint the bullet with a red sharpie. Shoot it in a group of four normal seating rounds for practice. The sharpie ink will mark the paper where it hit. Try for yourself and see what happens
 
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