If you normally feed from a magazine, whether it be lever, pump or bolt, I would use the SAAMI specs that are in your reloading manuals to ensure that your reloads feed reliably. If you have a single shot or a bolt gun that you feed individually, then you can adjust the COAL for accuracy. This will likely result in a cartridge that is longer than the SAAMI spec and may not feed well from your mag.
How do you measure your c.o..a.l?
- Thread starter nomad 68
- Start date
nomad 68
CGN Ultra frequent flyer
Once I determine the distance to the lands, I back off .010" and try it in the mag. If it feeds, great. If not,back of some more and repeat etc. Where is everyone begging up your lock n load gauges and mod cases?
257Roberts
CGN frequent flyer
- Location
- Peterborough ON
I looked at the Hornady tool and was wondering, Do they take the OAL from the shoulder or from the end of the case?
From what I see it would be the relationship from the shoulder to where it contacts the rifling.
I know you measure from the end of your adapter cartridge but how do you know if the head is in the right place in relationship to the bolt face?
Just trying to find the fly s..t in the pepper that's all.
David
From what I see it would be the relationship from the shoulder to where it contacts the rifling.
I know you measure from the end of your adapter cartridge but how do you know if the head is in the right place in relationship to the bolt face?
Just trying to find the fly s..t in the pepper that's all.
David
They take it from the 'ogive', the point of the bullet that comes in contact with the lands. You need a different insert for each caliber.
257Roberts
CGN frequent flyer
- Location
- Peterborough ON
I realize that, it's actually the point at where the ogive meets the lead of the rifling but where is the reference point as far as the case is concerned.
I also measure my ogive reference point with loaded rounds as a comparison to each different bullet that I reload. I have found that there is as much as .015 difference between bullet manufacturers depending on the shape and radius of the ogive. At one time I thought all lengths would be the same from case head to bullet ogive but they are not at all.
I just realized I need a new hobby, one that keeps me away from the loading bench during cold weather.
David
Not so you can get the coal quite a bit longer in most cases and still have them fit in the mag
and, depending on the bullet the full mag length might be too long.
If you are not using the Hornady gauge or something comparible then you are wasting your time.
Measuring to the tip of the bullet is equally pointless.
COAL is in general a pointless measurement except for fitting the rounds into a magazine. The only really useful measurement is from the ogive to the lands.
Measuring to the tip of the bullet is equally pointless.
COAL is in general a pointless measurement except for fitting the rounds into a magazine. The only really useful measurement is from the ogive to the lands.
yes. Once you have a seating depth the way you like it, say 20 thou off the rifling, you should take a measure from teh case headto the ogive and then you can replicate this distance with different shaped bullets.
To locate the ogive, you need something that will sit on the bullet ogive. I use a piece of barrel. A gunsmith can cut you a piece out of a scrap barrel of the right caliber.
Father Hood
Regular
- Location
- Lower Mainland, BC
Hornady Lock-N-Load OAL gauge and modified case and comparator to measure from base to ogive as others have mentioned. Works great. If I can't find the particular modified case, I make one myself with either a once fired (in that specific rifle) or FL resized case and a 5/16 x 36 tap that I ordered online.
I also make my own modified cases, using a case fired in that specific rifle. This eliminates any difference in actual length that may be there with a new case.
Then, I use a piece of barrel to establish actual ogive to land distance, as Ganderite showed.
Once that is established, all subsequent bullets can be compared and seated accordingly.
In some rifles, of course, the magazine length is the determining factor.
Regards, Dave.
Then, I use a piece of barrel to establish actual ogive to land distance, as Ganderite showed.
Once that is established, all subsequent bullets can be compared and seated accordingly.
In some rifles, of course, the magazine length is the determining factor.
Regards, Dave.
- Location
- West Quebec
Hornady Lock-N-Load OAL gauge here works great ...
