Just got the LNL OAL gauge for getting the OAL for my 338 LM. I'm going to load 225 gr. Hornady SST. I decided to measure 5 bullets seated in the modified case to get an average length. After getting the five measurements I noticed I was getting a variance in length anywhere from .008 to .010. This seems like a lot of difference in lengths. I'm using the .338 comparator insert and obtaining these measurements from the ogive. Is this a normal variance? I'm not using too much pressure when pushing the bullet to the lands so the wire should not be flexed when I lock it in place. Any help with this would be appreciated.
Hornady oal gauge measurement problems.
- Thread starter jbarber
- Start date
Help Support Long Range Hunting Forum
MudRunner2005
Well-Known Member
Use the same bullet to measure 5 times. Write down all 5 measurements, add them together, then divide by 5 to get your average length.
Mikecr
Well-Known Member
Over & over I read where folks end up averaging a reading with this method.
What a terrible system..
What a terrible system..
MudRunner2005
Well-Known Member
If the rod wasn't made of plastic and sticks inside the main body, it would be alot easier.
So what is your method?
Mikecr
Well-Known Member
I use an R-P Tool, which is basically the cleaning rod method. Woods posted great pictures here: Reloader's Nest Forum - OAL
But even soft seating is better than the stoneypoint/Hornady method, as it removes the shoulder from variance and takes the measure hard to boltface.
But even soft seating is better than the stoneypoint/Hornady method, as it removes the shoulder from variance and takes the measure hard to boltface.
earlcurtis67
Well-Known Member
For me, the problem with the cleaning rod method was seating the bullet to the lands at a consistant debth. I now take the spring out of the bolt and use bolt pressure, a sized case and my seating die to work down to where the bolt just drops down with no resistance. this method is the only one i've tried that will give me a repeatable measurement.
However, after reading the link that mikecr put up, i thought the idea of coloring the bullet with a sharpie to mark bullet debth in the case was a good one, ( if i we're to use the cleaning rod method) E
However, after reading the link that mikecr put up, i thought the idea of coloring the bullet with a sharpie to mark bullet debth in the case was a good one, ( if i we're to use the cleaning rod method) E
barefooter56
Well-Known Member
- Joined
- Nov 10, 2014
- Messages
- 913
Mud Runner2005,
Its not unusual to get different OAL lengths when using any type of OAL tool as its virtually impossible to apply the same pressure to the bullet each time. Also the more you measure with the same bullet the farther it goes into the lands due to the soft copper jacket. What I do when using either the Sinclair or Hornady tools is to run some dry patches down the barrel first to remove any oil in the barrel or in the chamber. When doing the bullet insert up to the lands part of the operation the bullet is pushed in lightly until I feel it stop. When I get to the building the dummy round step I use a once fired neck sized round, the bullet used to get the measurements and seat the bullet to the sum of the measurements found. Then take some 0000 steel wool , polish the tarnish off the bullet and chamber the dummy round slowly in the rifle , extract it and check the bullet for lands marks. If The barrel is a 4 groove you want to see 4 lands marks on the bullet, 5 groove 5 and so on. The lands marks will probably have some length on them depending on the pressure used during the measurement phase. Now adjust the seater stem down slightly, polish the bullet again , seat the bullet a little deeper and recheck the lands marks. Repeat until you end up with the lands marks on the bullet being about as thick as the point on a very sharp #2 pencil. You are still in the lands a little but if you go any deeper with the bullet you will use your reference point on the bullet. Now measure dummy round from base to ojive with a bullet comparator and calipers to get your comparator length to the lands. Keep this round and use it as a gauge to setup seating dies and to use to measure your throat wear. There are many ways get your OAL to the lands . I use this one.
If you need any more help please feel free to contact us! Thanks for using our bullets!
Take care,
Phil Hoham
Berger Bullet Tech
Its not unusual to get different OAL lengths when using any type of OAL tool as its virtually impossible to apply the same pressure to the bullet each time. Also the more you measure with the same bullet the farther it goes into the lands due to the soft copper jacket. What I do when using either the Sinclair or Hornady tools is to run some dry patches down the barrel first to remove any oil in the barrel or in the chamber. When doing the bullet insert up to the lands part of the operation the bullet is pushed in lightly until I feel it stop. When I get to the building the dummy round step I use a once fired neck sized round, the bullet used to get the measurements and seat the bullet to the sum of the measurements found. Then take some 0000 steel wool , polish the tarnish off the bullet and chamber the dummy round slowly in the rifle , extract it and check the bullet for lands marks. If The barrel is a 4 groove you want to see 4 lands marks on the bullet, 5 groove 5 and so on. The lands marks will probably have some length on them depending on the pressure used during the measurement phase. Now adjust the seater stem down slightly, polish the bullet again , seat the bullet a little deeper and recheck the lands marks. Repeat until you end up with the lands marks on the bullet being about as thick as the point on a very sharp #2 pencil. You are still in the lands a little but if you go any deeper with the bullet you will use your reference point on the bullet. Now measure dummy round from base to ojive with a bullet comparator and calipers to get your comparator length to the lands. Keep this round and use it as a gauge to setup seating dies and to use to measure your throat wear. There are many ways get your OAL to the lands . I use this one.
If you need any more help please feel free to contact us! Thanks for using our bullets!
Take care,
Phil Hoham
Berger Bullet Tech
