I see that you would prefer to send your brass to Horandy
To make a custom brass hull which will fit your chamber's dimensions exactly , really is not that complicated which I'm certain that you already are aware of , however there is something that is soul satisfying by fabricating your own.
( At least to myself )
All you will need is a fire formed shell case from each rifle ,carefully setting each case aside to be modified.
In the following manner you can create as many as you desire specific cases for every rifle you own in as many calibers as you need.
All these tools can be purchased locally except perhaps your tap which must be ordered.
If you do not wish to purchase anything refer to optional
1) a drill press with mounted vise
2) A letter (l) or a Letter (L) number drill
3) Coolant to prevent brass galling.
4) A number 5x32" X 36 TPI tap
5) Some scrap hardwood
6) One fire formed case ( caliber specific )
7) A T handle , or flat tap wrench.
8) Optional A Sinclair expander die with an .+001" oversize mandrel.
9) Your invested time , which would be less than5 minutes per case once you are all set up.
( using a lathe, by hand about 15 - 20 minutes )
I wont bother you with the how to's ( Visit the web for that ) suffice to say
Yes , there are other methods to achieve the same results, but both ways have worked in the past for me.
Optional
Find a friend who has access to a lathe and omit steps one through seven.
Either way it is a relatively easy task to perform.
This way you can make as many as you need in different calibers remembering which brass hull is associated with which rifle. ( Just color code your brass shell cases heads with magic marker remembering to document which case goes with which rifle, and which color that is designated for each rifle.
This is done for further referencing in the future.
I hope that may guide you in your decision.
