Cut neck COAL gauge

[Wolfdog91]

Just quick question. For everyone using a cut neck case for measuring COAL / CBTO how do y'all go about it ? Do you use just a fire formed piece of brass pop the primer and that's it ? Or do you realize and bump the shoulder back like you do with all your other brass for that gun ?
Thanks

 

[mikecr]

Let me help you with terms here. "Measuring COAL / CBTO" is just that: cartridge overall length, cartridge base to ogive. These are independent of shoulder or leade relationship.

I assume you mean COAL/CBTO -at land touching length, or maybe at jam length.
When I used a split neck for this in the past, I just cut one side of a new (but culled, mandrel expanded) case with a dremel.
With that, I log touching as max CBTO w/xxx bullet, and throw the case away. Done with it.

 

[K22]

I've seen it done both ways, i.e., a sized case with the prescribed bump and a case that has been fired so it is fired formed to the chamber. Both "camps" claim their method is more precise. I really don't know. I think both methods will give you a reasonable estimate of jam length.

Before I adopted using the Frankfort arsenal tool method of determining max COL (both touching the lands and jam length) I used a sized case with the bullet seated out far enough so it would jam the lands and push the bullet back.

However, I never used a split case. I placed a small amount of mineral oil around the circumference of the bullet which helped prevent the bullet sticking in the lands. This worked for me without having to split the case. I never had a bullet stick in the lands using this method.

After the measurements, I pulled the bullet, resized the case and placed it back in service.

 

[Ringostar]

If your fire formed brass still fits your chamber, then why are you sizing it back? This should help you understand!

 

[6BRA]

It's off the shoulder...doesn't matter

 

[Fclassfool]

Just size a little of your neck seat the bullet long and close the bolt on it then you can work into and out of the lands that's the way I do it anyway.

 

[Hoot]

Keep in mind that if you use a piece of fire formed brass, there's no need to cut the neck in order for the bullets to slide back into it. As was already mentioned, just size a small amount of the neck down to yield a slight grip on the bullet, I size my case like I'm going to reload it, including the shoulder bump if needed as that's the way all the subsequent cases will be presented in the chamber and then slit the neck. At least that's how I would do it if I didn't own a Stony Point / Hornady Overall Case Length Gauge. I work with a lot of different calibers. Rather than buy a threaded case for each of them, I just bought the tap and make my own.

Hoot