For example, if a rifle shoots well at a 2.80” OAL, what benefit would be gained loading .02” off the lands to 2.86” OAL? Can the small gain in case capacity net a faster velocity within similar pressures using a bit more powder to take up space? I’m assuming this is the same principal just on a smaller scale between a .308 win and a 30/06 or a 6.5CM compared to a 6.5prc. Similar pressures net more velocity in the larger case. It just takes more powder to get it there. Am I on the right track?
What is the advantage to loading long
- Thread starter wade2big
- Start date
You may have a broader jump node and or powder charge node at the longer coal. Or the reverse may be true.
The three potential advantages in my mind, in order of magnitude, are:
1) Keep the bottom of the bullet bearing surface out of the neck/shoulder junction (not always feasible for longer cartridges in a short action)
2) Bullet might like being closer to the lands (I don’t personally find that seating depth nodes are very far apart, more like 0.010-020” apart, not 0.100” apart)
3) More powder capacity (it takes a LOT of seating depth change to buy enough case capacity to yield meaningful MV increases)
1) Keep the bottom of the bullet bearing surface out of the neck/shoulder junction (not always feasible for longer cartridges in a short action)
2) Bullet might like being closer to the lands (I don’t personally find that seating depth nodes are very far apart, more like 0.010-020” apart, not 0.100” apart)
3) More powder capacity (it takes a LOT of seating depth change to buy enough case capacity to yield meaningful MV increases)
More case volume means less pressure which means a smidge more powder for a smidge more velocity potentially. Or the same velocity at a slightly lower pressure.
If you can keep the bullet above the neck shoulder transition then brass migration and pinching is one less thing you can worry about.
I find stuff is most accurate closer to the lands vs large jumps, maybe not as forgiving but more accurate if you can keep it loaded where it’s happy.
If you can keep the bullet above the neck shoulder transition then brass migration and pinching is one less thing you can worry about.
I find stuff is most accurate closer to the lands vs large jumps, maybe not as forgiving but more accurate if you can keep it loaded where it’s happy.
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