August 4th, 2020

Bullet Tip Touches Comparator Body Before Ogive Reaches Insert

Bullet ogive comparator gauge tool drill fix hybrid ogive bullet

Bullet ogive comparator gauge tool drill fix hybrid ogive bulletDo you shoot long, pointy Hybrid Ogive bullets? If so, you may need to modify the Hornady L-N-L Bullet Comparator tool commonly used to measure the distance from bullet base to bullet ogive.

With modern, high-BC match bullets, so much of the bullet may extend forward of the ogive that the bullet tip actually contacts the inside of the red comparator body BEFORE the bullet’s ogive contacts the gray caliber-specific insert ring attached to the red body. When this happens you will NOT get an accurate Base-to-Ogive (BTO) measure. And likewise you will not get a proper Cartridge-Base-to-Ogive (CBTO) measurement with loaded rounds.

Watch this video — it shows exactly how this measurement “fail” can happen with a .338-caliber Berger Elite hunter bullet. The tester was getting a false bullet Base-to-Ogive reading of 1.175 (0:25 timemark) before modifying his tool. The true BTO measurement, with the bullet actually contacting the gray comparator ring, is 1.121 (1:25 timemark):

How to Fix the Problem
What’s the fix? With a drill, you must relieve the back “wall” inside the red comparator holder bore. This will provide more clearance for the bullet tip. With more clearance the bullet ogive will seat properly on the gray, caliber-specific insert. The tip will no longer bottom out on the red clamping half of the tool.

The maker of this helpful video, EuLRH explains: “As we all know the CBTO (Cartridge Base to Ogive) measurement is [more useful than] COAL (Cartridge Overall Length). There are lots of products that can do this. One of them is Hornady L-N-L bullet comparator. Attention! With modern long range bullets it is possible that the bullet tip is touching the comparator body instead of the bullet ogive touching the gauge.” In this example, EuLRH worked with the 300gr Berger elite hunter bullet in .338 Caliber.

Why You Need to Check with Your Own Loads
If your bullets have this “tip touching” issue, when you measure your loaded rounds you will be seeing COAL instead of the Cartridge Base to Ogive (CBTO) length. Take a moment, test with your own bullets and your comparator to determine if you have this measurement problem. If you do, try the drilling solution shown in the video.

Credit Boyd Allen for finding EuLRH Video.