Hornady vs. Sinclair bullet comparators

[uncle-buck]

I have been using a Hornady bullet comparator for a few years and just upgraded to Sinclair (or so I thought). The Sinclair inserts contact the bullet surfaces in different places than the Hornady inserts.

Which ones contact the bullet at the actual ogive?

 

[Doom]

Probably neither. These are comparators and the measurements are only relevant to measurements made on different rounds made with the same device.

 

[Dusty Stevens]

^ exactly

 

[tmwinds]

You can't measure with a comparator. You can only compare.

 

[spclark]

Which ones contact the bullet at the actual ogive?

Uh, they both do.

Ogive is defined as the portion of a bullet's shape ahead of the bearing surface, with the very front end being tagged with the name meplat.

What you're asking I trust is more like: which comparator most closely approaches where your chosen bullet first encounters your barrel's lands, yes?

So likely neither Hornady nor Sinclair's will give you that. What's most trustworthy is a gage made from a cut-off of your barrel that's had a throat cut with the same reamer used to cut your barrel's chamber. Most will include a shoulder so as best to give you the same chamber dimensions as your barrel from the sidewall/shoulder junction forward. Most of us refer to this as a 'gizzy' so you know what to ask for from your gunsmith.

 

[uncle-buck]

Thanks for the replies, gentlemen. Very helpful.

 

[group therapy]

You can't measure with a comparator. You can only compare.

 

[Rsadams]

There's a very good article on the use of these tools and the different styles of tools available....

 

[J F Johannes]

I use the Sinclair comparator bodies with the Hornady inserts. I don’t like the offset on the caliper jaws with the Hornady bodies, which I believe is to use with their gauge thingy attached to their modified case. I don’t use their method to find lands or headspace(fu Guffey), I use the Wheeler method.
Jim

 

[uncle-buck]

I use the Sinclair comparator bodies with the Hornady inserts. I don’t like the offset on the caliper jaws with the Hornady bodies, which I believe is to use with their gauge thingy attached to their modified case. I don’t use their method to find lands or headspace(fu Guffey), I use the Wheeler method.
Jim

I didn't see much difference between the Hornady and Sinclair bodies other than the colors and sizes of the set screws. Removed the screws from both, weighed them, and found only less than 1 grain difference in weight between them.

 

[Mikemci]

I prefer the Sinclair. The insert is stainless steel and my cartridge just seems to settle in quicker and more stable.

 

[J F Johannes]

I didn't see much difference between the Hornady and Sinclair bodies other than the colors and sizes of the set screws. Removed the screws from both, weighed them, and found only less than 1 grain difference in weight between them.

These are the ones I have. Sinclair (top-black/green), Hornady (bottom-red). Hope you can see the offset in picture.


Jim

 

[jepp2]

Most of us refer to this as a 'gizzy' so you know what to ask for from your gunsmith.

 

[Ned Ludd]

Having a "gizzy" is probably the best you're going to be able to do. However, even that is not perfect as the rifle's throat will erode over time and the "gizzy" will not, thus changing their relative contact points on the bullet ogive. The bottom line is that for most shooters, these measurements are relative, and there is more than one way to make the measurement that will suffice, whether you just want to establish a baseline reference point for seating depth testing, or chase the lands as they erode. Choose a method that is consistent and provides the specific results you're after.

To the OP, the cartoon below might help explain better the difference between the two types of comparator inserts. As has been noted, the Hornady insert has a smaller "hole", and therefore seats farther out on the bullet ogive than does the comparable Sinclair insert. So, is that a good thing or a bad thing? Is one better than the other? The answer is, probably neither one is "better".

The Hornady insert seats a little closer on the bullet ogive to the point the seating die stem contacts the bullet and pushes it into the case (i.e. farther out on the ogive). That might make for a little more uniform seating depth readings (i.e. the closer those two points are together, the less bullet nose length variance is likely to affect seating depth measurements). The Sinclair comparator insert seats a little close to the bullet ogive/bearing surface junction, which is probably a bit closer to the actual point on the bullet ogive that will first contact the rifling, which might be a little more accurate. The Hornady insert is aluminum, the Sinclair insert is steel, etc., etc., etc. Either one can do the job effectively if you use it correctly and carefully record your measurements.

 

[Lefty Trigger]

The key is to use only one and don't mix them up. Pick one brand and stick with it for all your measurements.

 

[uncle-buck]

These are the ones I have. Sinclair (top-black/green), Hornady (bottom-red). Hope you can see the offset in picture.
View attachment 1131204

Jim

I see what you mean. You are absolutely correct. Thanks for the enlightenment.