FULLBORE Bullet Analysis

[BryanLitz]

I've posted a new article to my website titled: 2009 FULLBORE Bullet Update.

This article provides analysis of 8 different 30 cal 155 grain bullets that are commonly (and uncommonly) used in Fullbore competition.
The article starts by providing the tested BC's for each bullet, then goes on to analyze the effect of the different BC's on wind deflection and score for 1000 yard (US) prone and F-class targets.

Analysis is also provided on MV and performance from service rifles, which will be relevant to those with short barreled bolt rifles as well. Stability requirements for this current crop of FULLBORE bullets is also addressed.

Note this article does not address the terminal performance of any of the bullets. The Berger VLD and possibly the Hornady Amax are the only two bullets that would be viable for hunting. I'm sharing this here for those interested in the external ballistic analysis.

Enjoy,
-Bryan

PS, Please let me know ([email protected]) if you notice anything 'fishy' about the .pdf. Sometimes the font goes haywire, don't know if it's a browser problem, embedded fonts, etc. Thanks.

 

[jmason]

Awesome report Bryan! It's very interesting to see what a small margin there was between those bullets in your analysis. "Talk" would lead one to believe it would have been much more substantial.

 

[royinidaho]

Bryan,

I've been studying this report and Understanding LRBs parts 1&2 and the Fullbore report.

It's good that there is someone who has a handle on this stuff and is willing to share.

It's also great that you have so many interested people on this forum.

May I ask a couple of questions as my interests in bullet design and selection may be somewhat unique:

I noticed in Figure 2, Modern Fullbore Bullets, that the diagrams in the left column appear accurate when compared to the bullet images along the top.

'nother question(s): What would be considered an aggressive secant ogive?? What would be considered too aggressive?

I'm finding this stuff pretty exciting.
What caught my eys is the difference in bearing surface length compared to overall length. The Berger Fullbore appears among the shortest. How can that be accomplished with over all lengths being very nearly the same?

Next:

I was studying a box of the earliest Hornady spire points. These seemed more like collectors items but the fella shoots them. Their shape appears to be a straight line from ogive to point. The HBC BJD bullet seems very straight pointed and the VLD nearly so. So, why not just do a straight taper from ogive to point and make it as long a one wants to?

Edited below:
After more studying, my question about "straight pointed" seems to suggest a "cone" ogive radius which has received very little activity. The cone idea must have proven to be a dud? Possible a little curve is necessary?