Question on Determining the Correct OAL Measure to Use

[gerrym526]

Guys,

I'm loading 38special. Bullet is a Rainier Ballistics 158grain FP (copper jacketed). In using both the Hornady and Lyman guides I find the following info
1) Lyman-for a 158 grain jacketed HP, OAL length recommended is 1.480
2) Hornady-for a 158 jacketed FP (Hornady XTP bullet, not Rainier) recommended COL (which I assume is the same as OAL) is 1.450.

Since neither manual has the bullet I'm loading, how should the OAL be determined? And, how critical is the measurement itself-ie. can there be a range of acceptable OAL provided it doesn't exceed the maximum length listed.
Thanks for the help on this one.
Gerry

 

[rcmodel]

Yes there is a range of acceptance.
Unless you are loading max loads, seating depth is not real critical.

The info for the Hornady JFP should be pretty close to right for the Rainier PFP of the same weight you have.
You don't want to use JHP info with a solid FP, as bullet length is quite different for the same weight.

Bottom line is, they have to be short enough to fit inside the cylinder and allow it to rotate.
But not so short you have to crimp on thin air on the nose ogive.

rc

 

[gamestalker]

Don't those have a canelure? If so just crimp in the middel or at the back of the canelure and you'll be just fine.

 

[Hondo 60]

I'd probably go with what rcmodel said.

You want to go with bullet data that's as close to your bullet as possible.