Tool for measuring cartridge length from the ogive

[SteveOak]

I'm looking for a tool to measure cartridge length from the ogive. The baseline would be the Sinclair Insert Style Bullet Comparator. It has the added bonus of being used to measure from the shoulder. I have a Mitutoyo SC-6 caliper so that would establish the base level of measurement accuracy.

Are there any other tools I should consider?

BTW, the Redding Instant Indicator Headspace and Bullet Comparator is not the direction I want to go.

Thanks!

 

[MagnumManiac]

The Hornady Lock ‘n’ Load has the inserts and anvil attachment to measure headspace or base to ogive length.
There is also a bullet comparator tool that looks like a nut that can measure bullet ogives alone. Simply add/subtract to get the desires dimensions.

 

[dkhunt14]

Another vote for the Hornady headspace tool. All you need is the inserts for bullets and a set for headspace. The same body is used for both. Matt

 

[Grimstod]

Aluminum inserts do not give the most accurate readings. Have a machinist make you a steel one. You only really need about two sizes to cover every caliber as they do not need to be an exact fit. I made myself several. They are not hard to make.

 

[Dusty Stevens]

Aluminum inserts do not give the most accurate readings. Have a machinist make you a steel one. You only really need about two sizes to cover every caliber as they do not need to be an exact fit. I made myself several. They are not hard to make.

How hard are you squeezing those calipers down that aluminum deforms?

 

[hogpatrol]

 

[Regnar]

Datum Dial

 

[hogpatrol]

How hard are you squeezing those calipers down that aluminum deforms?

About the same amount used with these "C" clamps.

 

[357Mag]

SteveOak -

+1 on the Sinclair tool Hogpatrol posted a pic of.


With regards,
357Mag

 

[TerryH]

Davidson seating depth checker and base from Benchrite. Also works great for checking BTO on bullets. Slickest little deal I know of. Machined steel.

http://www.benchrite.com/cscart/index.php?dispatch=products.view&product_id=29858

http://www.benchrite.com/cscart/index.php?dispatch=products.view&product_id=29919

 

[Bart B.]

Will the chamber throat (leade) diameter and angle effect where on the bullet ogive's contact is made?

Does that contact point stay at the same place for the life of the barrel?

 

[SteveOak]

Will the chamber throat (leade) diameter and angle effect where on the bullet ogive's contact is made?

Yes

Does that contact point stay at the same place for the life of the barrel?

No. The leade erodes over time.

 

[SteveOak]

Thanks for the input. The Davidson looks like the ticket.

 

[jimbires]

am I missing something ? what does the Davidson tool do that the Hornady tool doesn't ?

 

[SteveOak]

am I missing something ? what does the Davidson tool do that the Hornady tool doesn't ?

The Hornady and Sinclair adapters have 4 interfacing surfaces between the caliper and bullet. The Davidson has only two thus fewer opportunities for precision and tolerance errors.

Some further observations. I am not knocking anyone here, just making observations.

Each manufacturing company has their own idea of a required level of precision and an acceptable tolerance. It is a business decision. As precision goes up and tolerances go down, manufacturing times and the costs go up. This makes the cost of goods sold higher so the company must accept less profit, do more marketing, or charge higher prices. Simple economics.

My impression of hierarchy of manufacturing quality;

Wilson. (Although they took a big hit with me this week.) Tier 1

Davidson. Acceptable quality.
Sinclair. Acceptable quality.
Redding. Acceptable quality

RCBS. Mostly or for plinking but not what I think of as precision for reloading.

Hornady. Not in the same class as the others.

Read this like a burn rate chart, not that there are six distinctive levels. Also, certain items from a manufacturer may be better or less than a similar tool from another manufacturer.

 

[Cloudrepair]

Thanks for the input. The Davidson looks like the ticket.

I like the idea of the Davidson one but I've already made mine about ten years ago then I got the hornady unit to go with mine.
I thought about making steel bushings but haven't neaded to yet.
Edit I'm sorry I think I ment the benchrite

 

[3Ackleys]

I have the Forster set and it has worked well for me

 

[hogpatrol]

My 2¢ One is just looking for a reference point so as long as the tool is used consistently, they all will work. The Hornady unit is an easy one to make custom inserts for.

 

[hogpatrol]

Will the chamber throat (leade) diameter and angle effect where on the bullet ogive's contact is made?

Does that contact point stay at the same place for the life of the barrel?

With some cartridges, that point won't stay in the same place after the first shot.

 

[dkhunt14]

The Hornady and Sinclair adapters have 5 interfacing surfaces between the caliper and bullet. The Davidson has only two thus fewer opportunities for precision and tolerance errors.

Some further observations. I am not knocking anyone here, just making observations.

Each manufacturing company has their own idea of a required level of precision and an acceptable tolerance. It is a business decision. As precision goes up and tolerances go down, manufacturing times and the costs go up. This makes the cost of goods sold higher so the company must accept less profit, do more marketing, or charge higher prices. Simple economics.

My impression of hierarchy of manufacturing quality;

Wilson. (Although they took a big hit with me this week.) Tier 1

Davidson. Acceptable quality.
Sinclair. Acceptable quality.
Redding. Acceptable quality

RCBS. Mostly or for plinking but not what I think of as precision for reloading.

Hornady. Not in the same class as the others.

Read this like a burn rate chart, not that there are six distinctive levels. Also, certain items from a manufacturer may be better or less than a similar tool from another manufacturer.

First of all, the Hornady is and was a Stoney point. I never had a problem measuring and holding .001 with it and with the inserts price, is very economical to load all the different cartridges and calibers. Matt