Make Your Own Prepared Cases for Hornady OAL Gauge

[Mountain]

I think this may have been mentioned somewhere within the guts of some thread. However, worth its own post since it works so well. Here's the drill and tap kit that works with the Hornady OAL gauges that require a prepared case:

https://www.amazon.com/gp/product/B0195UFBUY/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1

For reference, here's the OAL gauge that I use:

There's a straight one as well, but the curved version is necessary for semi's and works fine for bolt guns too. I've used this tool to develop several great shooting loads for various match rifles and my XP-100 pistols.

This drill and tap kit worked great to make prepared cases for some calibers like 7.5 Swiss, 7.62X54R, etc. and it works like a charm. Works great for the odd calibers and/or to save the trouble of ordering. Make two prepared cases and the drill and tap kit as pretty much paid for itself.

If you have your own workshop w/ lots of drills and taps, for reference the specs are
5/16" - 36 HSS Right hand Thread Tap, requires a 7.3mm Drill bit

 

[mac1911]

Cool, been meaning to do this myself . Although it’s just adding to the projects to be done.

 

[01SVTvert]

How do you get the case mouth .003 wider than normal so the bullet will slide in and out?

 

[EddieCoyle]

Are you using a fired case?

 

[TrashcanDan]

I had used a fired case in the past.
If I remeber correctly, I think I neck sized enough to hold a bullet, used some dykem blue just in case the projo got too far in, and went from there

 

[Mountain]

How do you get the case mouth .003 wider than normal so the bullet will slide in and out?

Are you using a fired case?

I have a fine round file that is a good size for opening up a ~.30 cal case mouth. Most of my rifles are .30 / 7.62. For 6.5 Creedmoor, .221 Fireball, and 50 BMG I just bought the Hornady prepared cases.

Generally I don't use a as-fired case. I'll size the cases then open up the mouth. If for one of my bolt guns that normally fires neck sized only, I'll use a fired case. I think the only fired case I am using is a 7mm BR for a custom XP-100. My loads for that are shooting close to 1/2 MOA at 100 yards with no signs of excess pressure so I think I'm good there.

Fired vs. unfired probably doesn't make a big difference so long as headspace is OK- I'm only determining the OAL that corresponds to the bullet just engaging the lands and adjust back a little for whatever 'jump' I want. I think if headspace was on the generous side a fired vs. non-fired case might increase the measured OAL a tad. In any case, I'll check loaded rounds to ensure I'm not jamming into the lands. I realize some calibers / loads are OK to be slightly jammed but I generally try to avoid that. Also for most if not all of my loads, I really don't need to push the envelope for velocity to get the best accuracy and there is a little buffer between my load and max load. I use a lot of Varget for the appropriate calibers- it's pretty stable and predictable the way I load it.

If you see any problems with my approach, I'm open to any guidance.

 

[mac1911]

Measure the actual case headspace on a hornady modified case.
I’m going to gander it’s close to minimum or even less.
I will also take a donut bet that only thing modified is the threaded end and slightly larger inside neck dia.

 

[pastera]

Make your own:
3/16 brake line, a #10-32 die, a coupling nut and a length of weed wacker line or music wire.

5/16-36 threads - shame on you for using a very non-standard thread so that people would be forced to use your accessories.

 

[Mountain]

Make your own:
3/16 brake line, a #10-32 die, a coupling nut and a length of weed wacker line or music wire.

5/16-36 threads - shame on you for using a very non-standard thread so that people would be forced to use your accessories.

Where the hell were you before I spent money on the Hornady stuff?

No kidding about their stupid thread selection!

 

[pastera]

Where the hell were you before I spent money on the Hornady stuff?

No kidding about their stupid thread selection!

With Polish, Irish and Italian in the blood line - I'm angrily stubborn about being cheap!

A top punch is what $12? Yeah too rich for my blood, I have a desktop machine shop($$$$) in the basement to make my own

 

[mac1911]

Make your own:
3/16 brake line, a #10-32 die, a coupling nut and a length of weed wacker line or music wire.

5/16-36 threads - shame on you for using a very non-standard thread so that people would be forced to use your accessories.

its early but why the weed wacker line

 

[pastera]

its early but why the weed wacker line

Flexibility -if you bend the brake line like the hornady tool, the plastic line is stiff along its length but bends. Plus most people don't have music wire hanging around but do have a weed wacker

 

[Nick Leduc]

Make your own:
3/16 brake line, a #10-32 die, a coupling nut and a length of weed wacker line or music wire.

5/16-36 threads - shame on you for using a very non-standard thread so that people would be forced to use your accessories.

Although I dont totally disagree with you on their thread selection, they most likely did it to have more thread engagement on certain cases.....

 

[pastera]

Although I dont totally disagree with you on their thread selection, they most likely did it to have more thread engagement on certain cases.....

36 pitch = 0.027"/thread
32 pitch = 0.031"/thread
Three threads of engagement gives full strength.
Cup height of primers is a minimum of .109" so a #10-32 has more than enough thread depth.


Why not use the same tap as their stuck case tool? (1/4-20)
https://www.amazon.com/Hornady-050033-Stuck-Case-Remover/dp/B004Y6ZJQ6

So I stand with my original position - they are a$$hats.