Hornady OAL Gauge Modified Cases?

engineer40

Well-Known Member
Joined
May 5, 2015
Messages
977
Location
Rockford, MI
I have a Hornady OAL Gauge in my Amazon cart right now and was also going to order their "Modified case" to thread onto the tool.

I read that it's better to send them your fire formed cases for them to thread and to not buy their SAAMI spec'ed modified case.

It seems like I could just use a tap and do this myself a lot faster than waiting for Hornady and the postal service.

Are there any downsides to just threading a fire formed case myself?

Or would you guys just buy the SAAMI spec modified case for $6?


Thanks!
 

MTBULLET

Well-Known Member
Joined
Jul 16, 2007
Messages
1,083
Do your own. the drill/tap combo pays for itself if you load for more than 3-4 rifles
 

engineer40

Well-Known Member
Joined
May 5, 2015
Messages
977
Location
Rockford, MI
Thanks MTBullet.

The Lapua brass I normally shoot is divided into perfectly equal lots of 20. I'd prefer to not to have one group of only 19 brass because I threaded one for this tool.

If I use a once fired Winchester or Prvi brass, will it be accurate enough measurement for my reloads with Lapua brass?

Thanks!
 

rcoody

Well-Known Member
Joined
Jul 1, 2015
Messages
1,026
Thanks MTBullet.

The Lapua brass I normally shoot is divided into perfectly equal lots of 20. I'd prefer to not to have one group of only 19 brass because I threaded one for this tool.

If I use a once fired Winchester or Prvi brass, will it be accurate enough measurement for my reloads with Lapua brass?

Thanks!

Personally I am lazy. I have the store bought ones that you can buy with the tool.

I then measure the shoulder on my fired brass and compare that to the saami one.

I find they are pretty close. Within .003 to .005

easy to make that adjustment in your overall length.
 

Black Tail Hunter

Well-Known Member
Joined
Dec 14, 2012
Messages
212
Location
Somewhere in the NW
I have made my own out of necessity since they dont offer every caliber. The tap is 5/16-36 i believe, you will likely have to get one online since most tooling stores dont have that size. If you are not doing this in a lathe be careful to keep the tap as straight as possible when threading, i have one that is off quite a ways and it is a PITA.
 

Rick Richard

Well-Known Member
Joined
Jan 7, 2014
Messages
4,110
Location
North Carolina
Cant understand why you would want to make one since the cost of one is less than the tooling to make it. Unless, it is a caliber that is not SAAMI.
 

tbrice23

Well-Known Member
Joined
Dec 12, 2012
Messages
3,077
Location
Indiana
Cant understand why you would want to make one since the cost of one is less than the tooling to make it. Unless, it is a caliber that is not SAAMI.

If he uses it more than once he is money ahead.

When you shoot 13 or 14 different chambering. Some of which is Ackley and wild cat chambers, you'd be a fool not to have the $6 tap.
 

engineer40

Well-Known Member
Joined
May 5, 2015
Messages
977
Location
Rockford, MI
Cant understand why you would want to make one since the cost of one is less than the tooling to make it. Unless, it is a caliber that is not SAAMI.

I did just order one. I wasn't concerned with the money, it's only $6. But some things I saw online people were saying that using a SAAMI spec brass that has NOT been fire formed to your chamber is not as accurate of a measurement.

That idea of it not being "as accurate" seemed even more relevant since Hornady themselves will thread one of your fire formed cases for you if you send it to them.

Truthfully, I'm fairly certain I've got very close to the OAL for my rifles in the past just using the "cleaning rod" technique. I just figured if I'm buying the proper tool, I might as well know the exact measurement. Not just a close measurement.


I appreciate everyone's opinions! Thanks again!
 

rcoody

Well-Known Member
Joined
Jul 1, 2015
Messages
1,026
I did just order one. I wasn't concerned with the money, it's only $6. But some things I saw online people were saying that using a SAAMI spec brass that has NOT been fire formed to your chamber is not as accurate of a measurement.

That idea of it not being "as accurate" seemed even more relevant since Hornady themselves will thread one of your fire formed cases for you if you send it to them.

Truthfully, I'm fairly certain I've got very close to the OAL for my rifles in the past just using the "cleaning rod" technique. I just figured if I'm buying the proper tool, I might as well know the exact measurement. Not just a close measurement.


I appreciate everyone's opinions! Thanks again!


be sure to measure three or four times and pick the one you get more than once.
 

ta406

Well-Known Member
Joined
Jun 15, 2011
Messages
89
Location
N. Idaho
I recently ran into the same problem as you and found this video to be very helpful.
 
Last edited by a moderator:

FEENIX

Well-Known Member
LRH Team Member
Joined
Dec 20, 2008
Messages
16,403
Location
Great Falls, MT
I recently ran into the same problem as you and found this video to be very helpful.
Making a modified case for Hornady OAL gauge on the mini-lathe - YouTube

He makes awesome helpful and informative videos.

That's the way to do it. Having said that, most us including myself does not have the same set up and it is not cost effective. $6 + the cost of the mini-lathe. :D

I'd love to have a mini-lathe (perhaps some day) but I too sends my spent case to have it modified and it works like a champ for my intended purpose.

Cheers!
 

engineer40

Well-Known Member
Joined
May 5, 2015
Messages
977
Location
Rockford, MI
I recently ran into the same problem as you and found this video to be very helpful.

It's interesting to me that he did a full length resize on his brass. I planned to do a very light neck resize, only enough so the brass will chamber in the rifle.

Thanks for sharing!
 

Garycrow

Well-Known Member
Joined
Jan 30, 2011
Messages
503
I have the tap but to be honest I just buy the modified cases any more. Using the tap is a PITA because I haven't found a good way to hold the case while drilling out the base. I've made it work by clamping them into a block of wood with a hole in it but it doesn't work well.

The measurements you get from the tool aren't precise enough anyway for the difference in headspace to make a difference. You're only going to get about a +/- .004" tolerance and that's more than the headspace dimensions. Anyone that tells you they're .002" off the lands is BS'ing you, a minute difference in pressure on the bullet will give different readings as the copper engraves the lands. The Hornady tool is great because it gets you near the lands so you can fine tune by actual shooting, but to claim absolute precision from it stretching it. If you're off by .006" because of the headspace due to a new vs. once fired case it's not going to make a bit of difference because you've got to tune it by shooting anyway. Anybody that has used them knows there's a bit of "slop" involved.
 

engineer40

Well-Known Member
Joined
May 5, 2015
Messages
977
Location
Rockford, MI
The measurements you get from the tool aren't precise enough anyway for the difference in headspace to make a difference. You're only going to get about a +/- .004" tolerance and that's more than the headspace dimensions. Anyone that tells you they're .002" off the lands is BS'ing you, a minute difference in pressure on the bullet will give different readings as the copper engraves the lands. The Hornady tool is great because it gets you near the lands so you can fine tune by actual shooting, but to claim absolute precision from it stretching it. If you're off by .006" because of the headspace due to a new vs. once fired case it's not going to make a bit of difference because you've got to tune it by shooting anyway. Anybody that has used them knows there's a bit of "slop" involved.


Thanks for this explanation Garycrow! That really helps put things into perspective!
 

Primary

LRH Assistant
Here are some related products that LRH members are talking about. Clicking on a product will take you to LRH’s partner, Primary, where you can find links to LRH discussions about these products.

 
 
Top