benchracer
Well-Known Member
- Joined
- Dec 18, 2009
- Messages
- 1,659
I was using YOUR words and YOUR links. I'm not the one with the problem in the discussion.
However the rest of what you are saying is a good discussion, back on topic.
No I'm not saying chamber pressure has anything to do with anything. I'm looking at the velocities. Some powders obviously give you more velocity with less pressure, non of which being the point, what I'm saying is that there has been a set of guidelines, with listed and tested velocities, with listed and tested twist rates that when deviated from, can, but not always, but has caused issues with bullet structure. Again, these elds have different bearing surfaces and different density thickness in jackets, then like stated in my previous example, a Sierra match king
If deviating, from what's factory recommended then things like this happens.
So you saying that 2800s to 3000s is regular velocities for a 147 gr is not accurate. velocity to projectile grain does effect structure. So you laughing at my logic means you are misinformed if you think otherwise.
A 130 gr .264 Winchester mag...I say again 130 grain....magnum....is only getting around 3100 FPS....if you are getting that in a heavier grain...hot rodding.
Extremely high velocity can cause bullet problems with fast twist barrels because of the inertia of the bullet not wanting to rotate causing engraving issues and in extreme cases jacket separation from the core. The heavier the bullet is at the same velocity, the worse the problem.
However even with proper twist barrels, depending on bullet design, velocity, can still cause structural issues. Especially bullets commonly used today where the body is very short placing more load on the surface of the bullet body.
There are only three things that cause bullets blowing up besides manufacture defects....cartridge/bullet/twist combinations.
There's good combines and bad.
Yes, velocity can (and does) cause structural failure. However, your assertion that is the cause of the reported failures is based on ZERO evidence. Your claim that 2750 from a 7.5 twist is sufficient to cause this failure is baseless and STUPID. Extrapolating that claim from max velocity quoted in a reloading manual, which is only a reflection of PRESSURE LIMITS at a given OAL, is just plain ignorant.
Hornady, themselves, have not asserted that the design limits of the 147 ELD-M were met or exceeded. On the contrary, they have stated they couldn't duplicate the issue and replaced the bullets. Maybe you should enlighten their engineers? I am sure there is a lot that they don't know about behavior of their bullets that you can explain to them.