How to measure distance from lands?
- Thread starter domyalex
- Start date
Many ways but this is my quick and easy method...
using a collet neck sizer, size a neck kinda loose by backing the die out, so that the bullet can be seated easily in and out by hand... but not too easily. hand start the bullet, chamber it in your gun and the lands will seat the bullet. remove and measure the oal then subtract .005-.020. remove that same bullet and use it to make your first round (this is to avoid variances in bullet lengths), slowly seating it a little at a time measuring after each adjustment until you reach your desired oal.
using a collet neck sizer, size a neck kinda loose by backing the die out, so that the bullet can be seated easily in and out by hand... but not too easily. hand start the bullet, chamber it in your gun and the lands will seat the bullet. remove and measure the oal then subtract .005-.020. remove that same bullet and use it to make your first round (this is to avoid variances in bullet lengths), slowly seating it a little at a time measuring after each adjustment until you reach your desired oal.
i am no champ reloader but measuring the oal sucks caue of lead tip bullet where the oal can change easy.. the method i use is close to the same but i measure to the ogive .
thats why i reccomended using the same bullet to set the die. alot of people dont have a length comparitor and i thought i would explain it in such a way that he could do it without needing another tool. i use a comparitor and also personally measure base to ogive.
I got caught up in measuring the OAL of the cartridges which used to really confuse me. How could I set a die, seat 5 bullets and the OAL's all measure differently.
With the bullets I buy they seem vary in length, weight and shape very slightly.
What I'm doing now, and seems to work for me is:
Determine seating die adjustments by seating a bullet at any length in the case. Measure the OAL. Then adjust the die a 1/4 turn and remeasure the OAL. Seems to be more accurate if you use a bullet with a plastic tip or basically anything with a solid tip to measure off of. Then I write down and keep track of the adjustment.
ie. 1/4 turn = 0.01 (or whatever it is)
Determine the max length the bullet can be seated in the cartridge (if not limited by mag box size). I do this by a guess and test process. Seat the bullet (in an empty case) really far out and slowly keep adjusting the seating die about 1/4 turn at a time until you can just barely close the bolt. This is the my starting point.
If you want to seat the bullet .010 off the lands, just adjust the die according the ammount you've figured out (ie 1/2 or 1/4 turn, etc)
Once Ive ajusted the die, I write on a piece of masking tape inside the die box where I've left it at. (max, 0.01, 0.02, etc)
Now istead of keeping track of OAL, I keep track of distance off the lands.
With the bullets I buy they seem vary in length, weight and shape very slightly.
What I'm doing now, and seems to work for me is:
Determine seating die adjustments by seating a bullet at any length in the case. Measure the OAL. Then adjust the die a 1/4 turn and remeasure the OAL. Seems to be more accurate if you use a bullet with a plastic tip or basically anything with a solid tip to measure off of. Then I write down and keep track of the adjustment.
ie. 1/4 turn = 0.01 (or whatever it is)
Determine the max length the bullet can be seated in the cartridge (if not limited by mag box size). I do this by a guess and test process. Seat the bullet (in an empty case) really far out and slowly keep adjusting the seating die about 1/4 turn at a time until you can just barely close the bolt. This is the my starting point.
If you want to seat the bullet .010 off the lands, just adjust the die according the ammount you've figured out (ie 1/2 or 1/4 turn, etc)
Once Ive ajusted the die, I write on a piece of masking tape inside the die box where I've left it at. (max, 0.01, 0.02, etc)
Now istead of keeping track of OAL, I keep track of distance off the lands.
I am using digital gauge from
http://www.larrywillis.com/
I do have my "dummy" round with bullet pushed to touch lands and then I can measure length of this dummy from ogilve and set this as zero.
Than I can push bullet back and measure distance from lands ,helps a lot when developing new load and playing with seating depth.
Andrew
http://www.larrywillis.com/
I do have my "dummy" round with bullet pushed to touch lands and then I can measure length of this dummy from ogilve and set this as zero.
Than I can push bullet back and measure distance from lands ,helps a lot when developing new load and playing with seating depth.
Andrew
You can use equipment such as the RCBS Precision Mic kit (that's what I use for "precision" calibers)
h ttps://shop.rcbs.com/WebConnect/MainServlet?action=CatalogSearch&langId=en_US&storeId=webconnect&catalogId=webconnect&screenlabel=index&pageSize=15&beginIndex=0&resultType=3&orderBy=1&searchType=0&searchDescription=precision+mic
Then choose the caliber you want.
the cheapest / more flexible gizmo you can use the Hornady (Ex-Stoney Point) OAL comparator auges; h ttp://www.hornady.com/store/OAL-Gauges/
But you will also need a specific to caliber "modified case" h ttp://www.hornady.com/store/Modified-Cases/
and a "bullet comparator kit" ht tp://www.hornady.com/store/Bullet-Comparator-Kits/
Always measure from an ogive diameter point.
h ttps://shop.rcbs.com/WebConnect/MainServlet?action=CatalogSearch&langId=en_US&storeId=webconnect&catalogId=webconnect&screenlabel=index&pageSize=15&beginIndex=0&resultType=3&orderBy=1&searchType=0&searchDescription=precision+mic
Then choose the caliber you want.
the cheapest / more flexible gizmo you can use the Hornady (Ex-Stoney Point) OAL comparator auges; h ttp://www.hornady.com/store/OAL-Gauges/
But you will also need a specific to caliber "modified case" h ttp://www.hornady.com/store/Modified-Cases/
and a "bullet comparator kit" ht tp://www.hornady.com/store/Bullet-Comparator-Kits/
Always measure from an ogive diameter point.
Unless you are using a bullet the same exact shape as the RCBS Precision Mic it is useless.
Better investments are the other 2 Stoney Point/Hornady options.
I use a dummy round that I chamber and reseat until it no longer leaves land marks on the polished bullet (use 000 fine steel wool to remove previous marks) then add .001 for my "to the lands" measurement with the "bullet comparator kit".
I never measure off the bullet tip since they can vary from .001-.020 in any given box.
Better investments are the other 2 Stoney Point/Hornady options.
I use a dummy round that I chamber and reseat until it no longer leaves land marks on the polished bullet (use 000 fine steel wool to remove previous marks) then add .001 for my "to the lands" measurement with the "bullet comparator kit".
I never measure off the bullet tip since they can vary from .001-.020 in any given box.
Thx a lot for all the replies 
Yeah, the guys at work (we have an internal reloading distribution list!) also suggested the Hornady Comparator and OAL gauge.
On the other hand, they also suggested "seating to standard depth", worry about bullet/powder first and then play around with seating depth when fine tuning.
Amazing the number of tools the reloader "needs"!
Yeah, the guys at work (we have an internal reloading distribution list!) also suggested the Hornady Comparator and OAL gauge.
On the other hand, they also suggested "seating to standard depth", worry about bullet/powder first and then play around with seating depth when fine tuning.
Amazing the number of tools the reloader "needs"!
Thx a lot for all the replies
Yeah, the guys at work (we have an internal reloading distribution list!) also suggested the Hornady Comparator and OAL gauge.
On the other hand, they also suggested "seating to standard depth", worry about bullet/powder first and then play around with seating depth when fine tuning.
Amazing the number of tools the reloader "needs"!
Sounds like the guys at work gave you the best advice. the distance to the lands is fine tuning once you have found "the load".
