O.A.L. Help - .308 Hornady 150 gr. FMJBT

McGlockster · October 9, 2007, 06:40 PM

Newbie question here, if you'd be so kind as to enlighten me.......

I'm loading .308 using Hornady 150 gr. FMJBT in Winchester brass using H-Varget powder (43-45 gr. charges) and Remington # 9 1/2 large rifle primers. The load data from a number of sources consistently indicates an O.A.L. of 2.8", but when I seat the bullet the crimp groove is well above the case mouth. If I set the seating die so that the crimp groove is halfway in/out of the case mouth I end up with an O.A.L. of 2.720". I'm using Lee dies (with the factory crimp die). Should I adhere to the 2.8" data, or seat it at the halfway mark of the bullet's crimp groove? BTW - the factory Winchester .308 168gr FMJ HP ammo I have on-hand measures out at 2.706" on the caliper.

Any input would be greatly appreciated.

Wildalaska · October 9, 2007, 07:10 PM

Seat on the crimp groove

WildbulletsareshortAlaska ™

sknowskier · October 10, 2007, 11:10 AM

Have you double checked your case length? My book says it should be 2.015. It also says with 150gr. jacketed SP bullets it should have a 2.685 OAL.
That's in my 47th Edition Lyman Reloading Handbook.

McGlockster · October 10, 2007, 02:10 PM

Ok, thanks Skier - time for me to invest in a few manuals. Thanks for the info.

30Cal · October 10, 2007, 05:24 PM

I would just ignore the cannelure. You don't need it and it's probably in a different place from one bullet to the next.

Ty

Splat!! · October 11, 2007, 06:46 PM

Quote:

My book says it should be 2.015

Isn't that Max length??............ I trim mine to 2.005

mrawesome22 · October 11, 2007, 07:56 PM

Take an empty case. Cut a vertical slit in the neck, barely into the shoulder, with a hacksaw. Barely seat the bullet you want to use in this case with your hands. Chamber this round in your rifle. Eject it with your hand covering the ejection port. Take it out and measure it from base to tip with your calipers. This will give you MAX OAL (over all length) for that bullet. In other words, this bullet is touching the rifling. Now you can experiment with different seating depths. I've found that my rifle usually gives best accuracy .030" away from the rifling. But you'll just have to experiment as to what shoots the best out of your gun. This method works very well and you don't have to waste money on a Stoney Point guage.

You don't need to crimp unless you're shooting an autoloader.

McGlockster · October 11, 2007, 08:07 PM

Interesting MrAwesome - I'll give it a whirl.

Wildalaska · October 12, 2007, 02:16 AM

Personally, having tried lots of methods, the Stoney Point is the most accurate

WildevenwithmyhomemadecaseAlaska TM

McGlockster · October 12, 2007, 01:51 PM

Thanks for the input everyone.

October 9, 2007, 06:40 PM	#1
McGlockster Member Join Date: September 7, 2007 Location: Duluth, Minnesota Posts: 44	O.A.L. Help - .308 Hornady 150 gr. FMJBT Newbie question here, if you'd be so kind as to enlighten me....... I'm loading .308 using Hornady 150 gr. FMJBT in Winchester brass using H-Varget powder (43-45 gr. charges) and Remington # 9 1/2 large rifle primers. The load data from a number of sources consistently indicates an O.A.L. of 2.8", but when I seat the bullet the crimp groove is well above the case mouth. If I set the seating die so that the crimp groove is halfway in/out of the case mouth I end up with an O.A.L. of 2.720". I'm using Lee dies (with the factory crimp die). Should I adhere to the 2.8" data, or seat it at the halfway mark of the bullet's crimp groove? BTW - the factory Winchester .308 168gr FMJ HP ammo I have on-hand measures out at 2.706" on the caliper. Any input would be greatly appreciated.

October 9, 2007, 07:10 PM	#2
Wildalaska Junior member Join Date: November 25, 2002 Location: In my own little weird world in Anchorage, Alaska Posts: 14,172	Seat on the crimp groove WildbulletsareshortAlaska ™

October 10, 2007, 11:10 AM	#3
sknowskier Member Join Date: August 10, 2007 Location: Lubbock, Texas Posts: 36	Have you double checked your case length? My book says it should be 2.015. It also says with 150gr. jacketed SP bullets it should have a 2.685 OAL. That's in my 47th Edition Lyman Reloading Handbook.

October 10, 2007, 02:10 PM	#4
McGlockster Member Join Date: September 7, 2007 Location: Duluth, Minnesota Posts: 44	Ok, thanks Skier - time for me to invest in a few manuals. Thanks for the info.

October 10, 2007, 05:24 PM	#5
30Cal Senior Member Join Date: December 3, 2002 Posts: 1,264	I would just ignore the cannelure. You don't need it and it's probably in a different place from one bullet to the next. Ty

October 11, 2007, 07:56 PM	#7
mrawesome22 Senior Member Join Date: November 9, 2005 Location: Ohio, Appalachia's foothills. Posts: 3,779	Take an empty case. Cut a vertical slit in the neck, barely into the shoulder, with a hacksaw. Barely seat the bullet you want to use in this case with your hands. Chamber this round in your rifle. Eject it with your hand covering the ejection port. Take it out and measure it from base to tip with your calipers. This will give you MAX OAL (over all length) for that bullet. In other words, this bullet is touching the rifling. Now you can experiment with different seating depths. I've found that my rifle usually gives best accuracy .030" away from the rifling. But you'll just have to experiment as to what shoots the best out of your gun. This method works very well and you don't have to waste money on a Stoney Point guage. You don't need to crimp unless you're shooting an autoloader.

October 11, 2007, 08:07 PM	#8
McGlockster Member Join Date: September 7, 2007 Location: Duluth, Minnesota Posts: 44	Interesting MrAwesome - I'll give it a whirl.

October 12, 2007, 02:16 AM	#9
Wildalaska Junior member Join Date: November 25, 2002 Location: In my own little weird world in Anchorage, Alaska Posts: 14,172	Personally, having tried lots of methods, the Stoney Point is the most accurate WildevenwithmyhomemadecaseAlaska TM

October 12, 2007, 01:51 PM	#10
McGlockster Member Join Date: September 7, 2007 Location: Duluth, Minnesota Posts: 44	Thanks for the input everyone.