Forster Datum Dial Ammunition Measurement System

[GeekWithGuns]

Anyone happen to have one of these kits?
https://www.midwayusa.com/product/377022/forster-datum-dial-ammunition-measurement-system-complete-kit-in-storage-box

I'm thinking to pick one up in next month or so. My thinking is to measure the datum from base of the case to case shoulder and compare that measurement between fireformed cases in my bolt-action or single shot chambers and then on resized cases to ensure that I'm setting the shoulder back far enough but not excessively during full length sizing operations.

My thinking is that not overdoing the resizing/shoulder setback minimizes stress on the case leading to longer case life and less problems (i.e. reduced chance of case neck separation on older cases).

Thoughts?

[MadPick]

I don't have any experience with a tool like this, so I'm totally talking about of my ass . . . but that's not going to stop me.

The theory sounds good, especially if you only have one gun in each caliber or if you segregate your brass and ammo.

However, I think I'd be inclined to use the money towards an annealer, if you're worried about case life. Or do you already anneal?

[GeekWithGuns]

I don't have any experience with a tool like this, so I'm totally talking about of my ass . . . but that's not going to stop me.

The theory sounds good, especially if you only have one gun in each caliber or if you segregate your brass and ammo.

However, I think I'd be inclined to use the money towards an annealer, if you're worried about case life. Or do you already anneal?

Good point about annealing. Recently read a precision shooting blog article that annealing is the most popular case prep operation performed by top shooters:
http://precisionrifleblog.com/2015/12/31/reloading-tips-from-top-precision-rifle-shooters/

I did recently pick up an annealing system:
https://www.cartridgeanneal.com/

Nice, low-cost solution considering the low volume of brass that I'm annealing.

In my case I do only have one gun or one barrel in each caliber and they're all bolt-action Rem XP-100 or single-shot Contender firearms. I guess the Forster datum tool is more like a fine-tuning, tweaking instrument. Just wondering if it's worth a benjamin.

[beckdw]

I think you can do basically do the same thing with case gauges. My LE Wilson gauges describe how to do set your dies up so they only set the shoulder back as far as necessary.

[rodell]

I don't have this specific kit, but I do have a setup to measure the case shoulder in a consistent way with a dial caliber and a collet. My only problem is the measurement can vary quite a bit depending on how much pressure you apply to the case at the measuring point. Once I learned to be consistent, it helps me set the shoulder with a very narrow band.

It takes a little while to learn how to be consistent and is frustrating until you do.