Sierra C.O.A.L

MuddyRiver · October 22, 2013, 05:15 AM

Noobie reloader here trying to figure out whether the listed C.O.A.L for the .243 BTHP bullet (#1530) is minimum or maximum. I checked a deprimed case loosely fitted with the bullet set long in my Savage chamber and got a length of 2.623 which I assume is on the lands. The Sierra manual for the #1530 bullet shows a C.O.A.L of 2.650. So if I set my bullet depth to, say, 2.610 will I have any pressure problems?

Thanks in advance for any help.

steve4102 · October 22, 2013, 06:03 AM

Forget the OAL listed in the manuals, seat your bullet so it works in your rifle, Then start low and work up.

Reducing OAL in a bottle necked rifle round most often times reduces pressure. The farther the bullet is from the lands/grooves the less the pressure. The small reduction in case volume by reducing OAL is very small % of case volume and insignificant in a case like the 243.

jwrowland77 · October 22, 2013, 07:23 AM

The OAL in the manual, is the OAL they used. Forget it about it. They have a different setup than you.

Load your rifle using your OAL that is safe. I use an OAL that is longer for MY rifle, but I load one at a time. If not, I'd load them to magazine length. So, just figure out what your OAL should be, and do your workup from there.

October 22, 2013, 07:23 AM	#3
jwrowland77 Senior Member Join Date: March 23, 2012 Location: Conway, Arkansas Posts: 1,398	Sierra C.O.A.L The OAL in the manual, is the OAL they used. Forget it about it. They have a different setup than you. Load your rifle using your OAL that is safe. I use an OAL that is longer for MY rifle, but I load one at a time. If not, I'd load them to magazine length. So, just figure out what your OAL should be, and do your workup from there.

October 22, 2013, 05:15 AM	#1
MuddyRiver Junior Member Join Date: August 1, 2009 Location: Kentucky Posts: 2	Sierra C.O.A.L Noobie reloader here trying to figure out whether the listed C.O.A.L for the .243 BTHP bullet (#1530) is minimum or maximum. I checked a deprimed case loosely fitted with the bullet set long in my Savage chamber and got a length of 2.623 which I assume is on the lands. The Sierra manual for the #1530 bullet shows a C.O.A.L of 2.650. So if I set my bullet depth to, say, 2.610 will I have any pressure problems? Thanks in advance for any help.

October 22, 2013, 06:03 AM	#2
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,955	Forget the OAL listed in the manuals, seat your bullet so it works in your rifle, Then start low and work up. Reducing OAL in a bottle necked rifle round most often times reduces pressure. The farther the bullet is from the lands/grooves the less the pressure. The small reduction in case volume by reducing OAL is very small % of case volume and insignificant in a case like the 243.