So, my 6.5 x 284 running 143 eldx has a length to the ogive of 2.460 inch.
Have bought some 140 Berger VLD and despite how many times I check the length to the ogive is 2.450.
Not seen or heard this before, anyone else seen this?
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So, my 6.5 x 284 running 143 eldx has a length to the ogive of 2.460 inch.
Have bought some 140 Berger VLD and despite how many times I check the length to the ogive is 2.450.
Not seen or heard this before, anyone else seen this?
May be deliberate, see this video, opening intro about reason hunters may want the ogive a bit back off the lands.
https://youtu.be/9OZ8u8e7mSc
Can always gently use a kinetic puller, then re-seat to desired length if it's important.
Haven’t loaded any yet. Was just checking seating how far out they seat
It’s a different projectile so sure to be Different???? Unless im not understanding the question?
Attachment 96638
Looks ok to me :thumbsup:
I’m measuring the length from the bolt face to the lands, not the overall length.Quote:
Originally Posted by rambo-6mmrem
I would have thought it is measuring from one fixed point to another.
If yoh think of a cone shape going into a hole the different angle cone will go into hole different distance, length from point on projectile that contacts lands to base of boat tail will vary between bullet designs, imaging this is what you are getting (assuming have read what you have put up properly)
I read it that you measured as if you havd seated each bullet to form the maximum cartridge OAL.
The Berger appears to have the more slender spire, and so engages the rifling from her hips down, and the slightly less top slender ELDX engages the rifling from her umbilicus down, so to say. Not sure it translates to any ballistic difference, except in required seating depth, as though the Berger has slightly more slender spire she is nevertheless lighter than the ELDX.
Exactly my thoughtsQuote:
Originally Posted by distant stalker
Have you remeasured with the 143 eld-x?
You are only talking a difference of a quarter of a millimetre, so not much in it. It could be the projectiles are slightly different diameters.
Different shape projectile
Yes Kalimata are long and pointy with a boat tail a good long range olive with lasting flavour it has applications in antipasto as well. lecciano round nosed and flat based a perfect choice for short to middle distance salads and cooking. Amfissa spire point boat tail a good allrounder for cooking salads or martinis.
Come on fellas, I know what I mean😂
It is the distance to the lands I am talking about. Haven’t loaded any ammo as yet, just comparing the distance I measure when using the hornady overall length gauge and the bullet comparator set which gives me the measurement to the bullet oGive.
Understand about the overall length being different just not sure why the distance to the lands seems different for the different projectiles
I think you have COAL and Base to Ogive mixed up? The COAL can be the same for any given projectile if you choose to seat it as such but the Base to Ogive will change depending on the projectile shape. Your lands cant move as they are part of the rifle but due to bullet shape the distance to the lands can vary even if seated using the same base to ogive measurementQuote:
Originally Posted by Mick Hunter
One thought...
SAAMI specs for 308 say lands at 7.62mm and grooves at 7.82mm. So I assume this means 308 projectiles are actually greater than 7.62mm diameter, otherwise you won't get any rotation from the rifling. .308 of an inch is actually 7.82mm
If your comparator insert is 7.62mm (or anything less than 7.82), it is actually contacting just before the true end/start of the ogive, and how far before the ogive will be affected by projectile shape. And the insert has to be at least a bit smaller than bullet diameter or it could travel the full length of the projectile and you wouldn't be able to get a meaningful measurement.
In effect, you are probably measuring where the projectile diameter equals the diameter to the lands, not the true ogive point. But that is what you want anyway to be able to set your jump so all good, but the measurement will vary slightly between projectiles.
I think adding olives was a complication too far.Quote:
Originally Posted by Gibo
[QUOTE=Cigar;753157]One thought...
SAAMI specs for 308 say lands at 7.62mm and grooves at 7.82mm. So I assume this means 308 projectiles are actually greater than 7.62mm diameter, otherwise you won't get any rotation from the rifling. .308 of an inch is actually 7.82mm
You are over thinking it, 7.62 is the bore diameter and 7.82 is the groove diameter in English/American .300" x .308" as you can't get .300" diameter bullets don't worry about it,
Just start with the bullets seated to Manufacturers specs and tweak from there, The ogive measurement is variable any way manufacturing tolerances being what they are there can
be a spread of .003" or more between bullets, The only way to get them all the same is to measure the base to ogive on all bullets and batch them, That gets boring very fast, unless you are OCD
If you are trying for a world record group at 1000 yards Ok, anything else it's a waste of time
