OAL question.

DAL · May 23, 2000, 03:11 AM

I hope that some of you old hands at reloading can help me with this. Are cartridges supposed to vary in length even when no adjustment has been made to the seating die? Without making any changes while seating the same bullets from the same box, I often can have as much as +/- .002" to .005" amount of variance in the OAL of the finished cartridge. Is this normal? Will this small amount of difference cause any detrimental effect on accuracy?
DAL

P.S. I trimmed all of my brass to the same length.

------------------
Reading "Capitalism: The Unknown Ideal," by Ayn Rand, should be required of every politician and in every high school.
GOA, JPFO, PPFC, CSSA, LP, NRA

**Bud Helms** · May 23, 2000, 05:49 AM

DAL,

That's not uncommon. It's usually not that much of a problem unless you're trying for extreme accuracy. In that case, the fly [color=#FF0000]█[/color][color=#FF0000]█[/color][color=#FF0000]█[/color][color=#FF0000]█[/color][color=#FF0000]█[/color] and the pepper definitely have to be separated. Those variations are why I don't try to get the bullet any closer than .010 to the lands.

You didn't say what you were reloading. Good quality jacketed bullets and starting out with a clean seating plug that matches your bullet is the easiest way to avoid the variations. It can make a BIG difference.

[This message has been edited by sensop (edited May 23, 2000).]

Banzai · May 23, 2000, 09:14 AM

It's pretty common, although i'd say that .005 would be a lot. Mine, rifle or pistol, average in teh +/- .002.
Take a look at the tips of your bullets and you'll see that most of the ones that are different from the average probably have damaged or different tips for some reason or another. This is especially true of soft point rifle bullets delicate tip hollow points, and some types of pistol bullets where the lead protrudes above the folds of the copper jacket.
Make sure that your seating plug matches the bullets as close as possible, too. It may be dirty. Another thing, make sure you're consistent with the handle stroke! I've caused myself much pain and anguish in the past with variable OAL just as you described by not being firm and consistent with my technique.
I wouldn't worry about it unless you're shooting benchrest!!

Tom

------------------
A "Miss" is the ultimate overpenetration!
You can never be too rich, too skinny, or too well armed!
Wake up and realize that you have the moral imperative of action..!!!

Bill Hebert · May 23, 2000, 09:32 AM

DAL, the amount of pressure you exert on the reloading handle is transferred to the bullet and accounts for some of the variation. Also, if you're reloading lead bullets, lead can build up inside the die causing the OAL to decrease as you reload more rounds. After I finish reloading the lead bullets I now have, I will only use copper plated. Do not treat OAL lightly or you do so at your own and your weapon's risk. Good luck. Bill

DAL · May 23, 2000, 05:53 PM

I'm reloading 165 gr. BT soft points from Speer for my .30-06 bolt action. Some of the soft points are slightly deformed from who- knows-what. I'm sure that accounts for most of the difference. When I get my Stoney Point OAL guage, and I can figure out the best OAL for my rifle, much of this will probably become largely inconsequential (I hope).

I'll keep an eye out for any build up of residue on the seating plug.

Thanks, guys!
DAL

------------------
Reading "Capitalism: The Unknown Ideal," by Ayn Rand, should be required of every politician and in every high school.
GOA, JPFO, PPFC, CSSA, LP, NRA

dongun · May 23, 2000, 09:07 PM

I've also experienced this problem and tracked it down to differences in bullet length. I was using 165gr Sierra Spitzer BTs. I measured about 20 bullets and most were within .002, but varied by .005" from shortest to longest. I tried Noslers and they were more consisent (makes sense, they cost about twice as much). However, my .308 likes the Sierras better than the Noslers (go figure). Them dead whitetails couldn't detect the difference. Good luck.

May 23, 2000, 03:11 AM	#1
DAL Senior Member Join Date: October 15, 1999 Location: Colorado Springs, CO, USA Posts: 653	I hope that some of you old hands at reloading can help me with this. Are cartridges supposed to vary in length even when no adjustment has been made to the seating die? Without making any changes while seating the same bullets from the same box, I often can have as much as +/- .002" to .005" amount of variance in the OAL of the finished cartridge. Is this normal? Will this small amount of difference cause any detrimental effect on accuracy? DAL P.S. I trimmed all of my brass to the same length. ------------------ Reading "Capitalism: The Unknown Ideal," by Ayn Rand, should be required of every politician and in every high school. GOA, JPFO, PPFC, CSSA, LP, NRA

May 23, 2000, 05:49 AM	#2
Bud Helms Senior Member Join Date: December 31, 1999 Location: Middle Georgia, USA Posts: 13,198	DAL, That's not uncommon. It's usually not that much of a problem unless you're trying for extreme accuracy. In that case, the fly [color=#FF0000]█[/color][color=#FF0000]█[/color][color=#FF0000]█[/color][color=#FF0000]█[/color][color=#FF0000]█[/color] and the pepper definitely have to be separated. Those variations are why I don't try to get the bullet any closer than .010 to the lands. You didn't say what you were reloading. Good quality jacketed bullets and starting out with a clean seating plug that matches your bullet is the easiest way to avoid the variations. It can make a BIG difference. [This message has been edited by sensop (edited May 23, 2000).]

May 23, 2000, 09:14 AM	#3
Banzai Senior Member Join Date: January 29, 2000 Posts: 275	It's pretty common, although i'd say that .005 would be a lot. Mine, rifle or pistol, average in teh +/- .002. Take a look at the tips of your bullets and you'll see that most of the ones that are different from the average probably have damaged or different tips for some reason or another. This is especially true of soft point rifle bullets delicate tip hollow points, and some types of pistol bullets where the lead protrudes above the folds of the copper jacket. Make sure that your seating plug matches the bullets as close as possible, too. It may be dirty. Another thing, make sure you're consistent with the handle stroke! I've caused myself much pain and anguish in the past with variable OAL just as you described by not being firm and consistent with my technique. I wouldn't worry about it unless you're shooting benchrest!! Tom ------------------ A "Miss" is the ultimate overpenetration! You can never be too rich, too skinny, or too well armed! Wake up and realize that you have the moral imperative of action..!!!

May 23, 2000, 09:32 AM	#4
Bill Hebert Senior Member Join Date: May 15, 1999 Posts: 180	DAL, the amount of pressure you exert on the reloading handle is transferred to the bullet and accounts for some of the variation. Also, if you're reloading lead bullets, lead can build up inside the die causing the OAL to decrease as you reload more rounds. After I finish reloading the lead bullets I now have, I will only use copper plated. Do not treat OAL lightly or you do so at your own and your weapon's risk. Good luck. Bill

May 23, 2000, 05:53 PM	#5
DAL Senior Member Join Date: October 15, 1999 Location: Colorado Springs, CO, USA Posts: 653	I'm reloading 165 gr. BT soft points from Speer for my .30-06 bolt action. Some of the soft points are slightly deformed from who- knows-what. I'm sure that accounts for most of the difference. When I get my Stoney Point OAL guage, and I can figure out the best OAL for my rifle, much of this will probably become largely inconsequential (I hope). I'll keep an eye out for any build up of residue on the seating plug. Thanks, guys! DAL ------------------ Reading "Capitalism: The Unknown Ideal," by Ayn Rand, should be required of every politician and in every high school. GOA, JPFO, PPFC, CSSA, LP, NRA

May 23, 2000, 09:07 PM	#6
dongun Member Join Date: May 7, 2000 Location: Central Arkansas Posts: 76	I've also experienced this problem and tracked it down to differences in bullet length. I was using 165gr Sierra Spitzer BTs. I measured about 20 bullets and most were within .002, but varied by .005" from shortest to longest. I tried Noslers and they were more consisent (makes sense, they cost about twice as much). However, my .308 likes the Sierras better than the Noslers (go figure). Them dead whitetails couldn't detect the difference. Good luck.