finding the lands

[JFrank]

May I respectively suggest finding the depth article at the Berger site. Someone here will have the link (at work and cannot poke around) It will give you the best jam or jump for your rifle based upon seating depth and shooting targets. It worked wonderfully for me. I.E. you may thing jamming .01 is best for you, but jumping .04 might really be the cat's meow.

Ah, there it is further up. Method also works for non VLD bullets

link

http://www.bergerbullets.com/getting-the-best-precision-and-accuracy-from-vld-bullets-in-your-rifle/

Thank you
My load is established as well as seating depth of .016 jump so just maintaining that is chore.
My rifle is telling me that even though the lot numbers are the same and the BBTO is the same they are different CBTO 1.798 vs 1.810 that's a big difference.
Skinny bullets?
J

 

[Dusty Stevens]

Thanks for weighing in Dusty'
My comparator is the only tool I got for this stuff, I use it for BBTO I use it for finding the lands CBTO and I use it to check seating depth. I worked up my load with CBTO at 1.798 to the lands then tested seating depth and ended up at 1.782 .016 jump all good right?
As I said the odd thing the same lot number bullets in the new box were 1.810 to the lands. My back up box is 1.798 to the lands again so at this point I feel I would need to retest the odd box I suppose. Alex made a great point not to start load development until he had enough components to wear it ' anyway Talk to me man
J

You see what i was saying about the seating stem contacting different points than the comparator? And also lot numbers mean nothing- at sierra they have so many bullets in processes getting tumbled, all that. The lots are numbered as theyre packaged and they have dumpster loads of bullets in there from multiple dies so it means nothing. Best way i can explain what im trying to say is take 10 that youve sorted the same with your comparator then seat them long in your die, crank it down shorter and measure the total die length then youll see how different your seating die seats them. Like this pic:

 

[JFrank]

View attachment 1050881

You see what i was saying about the seating stem contacting different points than the comparator? And also lot numbers mean nothing- at sierra they have so many bullets in processes getting tumbled, all that. The lots are numbered as theyre packaged and they have dumpster loads of bullets in there from multiple dies so it means nothing. Best way i can explain what im trying to say is take 10 that youve sorted the same with your comparator then seat them long in your die, crank it down shorter and measure the total die length then youll see how different your seating die seats them. Like this pic:

Ok great! I'm at work now so when I get home I'll study up. Do you mind if I have a follow up question?
J

 

[Dusty Stevens]

Ok great! I'm at work now so when I get home I'll study up. Do you mind if I have a follow up question?
J

Anything for you jim

 

[snakepit]

Bryan Litz the head bullet engineer for Berger Bullets recommends for Hybrid Bullets to start .015" off the lands and to work back when loading the Berger Hybrids. I throw this in because it seems like most of what has been discussed here is more along the lines of VLD bullets and with the Hybrids having become so popular it is good to hear what Berger has to say about seating them. This also includes a good video interview with Bryan.

http://bulletin.accurateshooter.com/2013/01/berger-hybrid-bullets-what-you-need-to-know/

 

[JFrank]

View attachment 1050881

You see what i was saying about the seating stem contacting different points than the comparator? And also lot numbers mean nothing- at sierra they have so many bullets in processes getting tumbled, all that. The lots are numbered as theyre packaged and they have dumpster loads of bullets in there from multiple dies so it means nothing. Best way i can explain what im trying to say is take 10 that youve sorted the same with your comparator then seat them long in your die, crank it down shorter and measure the total die length then youll see how different your seating die seats them. Like this pic:

Yes the comparator is just that -a comparator the seating stem will contact in a different location. Understood'
I took down a few of the rounds I have just made up and re measured and they were fine BBTO.688.5
CBTO 1.798- my reference to the lands
Seating at 1.782
Jump .016
So my thoughts after sleep are that a few Maverick bullets got shoveled off the floor and mixed in.
Sierras normally are pretty close this kinda threw me for a -what the hell!
So the picture- what am I looking at ? What's the black thing ?
I don't have one
J

 

[Dusty Stevens]

Sorry the black thing is a seating die

 

[JFrank]

Sorry the black thing is a seating die

Who made that?
Are the polished pieces Wilson ?
im not clear on how that works, is there a loaded round in there?
J

 

[Dusty Stevens]

No i made it all From barrel stubs. The black piece is a barrel stub thats chambered short then melonited. The base is adjustable inside for a perfect fit no matter what bump you have. The top has a stem kinda like a wilson with very fine clicks like .00025 i cant remember exactly. Its the only one i ever did for good reason. Zoom in you can see my name on it. Shouldnt have posted it really.

 

[searcher]

Do we really need to find the lands to the .001 of an inch or do we really just need a datum to start our seating test from. i know many have an unreasonable fear of jaming bullets but on my target rifles i always start load development jammed .010 or .020. That distance to the lands is a moving target anyway.

i use the stoney point and after years of practice can get consistent measurements easily to .002 or .003. My thoughts are that is plenty good for a starting point. I find that with a new barrel after 100 or 200 rounds with a well broken in throat that measurement is quite different and than it settles down.

I believe knowing for sure you are off or in the lands and maintaining a reference point is what is important. Granted, you want to know fairly close as to where you are - as the pressure spike needs to be anticipated when going deep - and you also want to know you are clear of the lands by at least .003" once out. Whether you are .002" or .005" off one way or the other matters little - it is how the gun reacts to the position you are in and making adjustments from your reference point.

 

[JFrank]

No i made it all From barrel stubs. The black piece is a barrel stub thats chambered short then melonited. The base is adjustable inside for a perfect fit no matter what bump you have. The top has a stem kinda like a wilson with very fine clicks like .00025 i cant remember exactly. Its the only one i ever did for good reason. Zoom in you can see my name on it. Shouldnt have posted it really.

Cats out of the bag now !

 

[JFrank]

Anything for you jim

My lazy Nefew needs a job

 

[JFrank]

May I respectively suggest finding the depth article at the Berger site. Someone here will have the link (at work and cannot poke around) It will give you the best jam or jump for your rifle based upon seating depth and shooting targets. It worked wonderfully for me. I.E. you may thing jamming .01 is best for you, but jumping .04 might really be the cat's meow.

Ah, there it is further up. Method also works for non VLD bullets

link

http://www.bergerbullets.com/getting-the-best-precision-and-accuracy-from-vld-bullets-in-your-rifle/

Thx I have seen that article, i have no experience with VLD however I would probably try that method I do believe with secant ogive bullets seating depth is a little trickier.
J

 

[KenOath]

Looks like I’m in the minority here but I don’t have any problems finding a consistent lands measurement with the Hornady tool and Sinclair Stainless Steel insert, can always get within a couple thou... use to double check with the striped out bolt method but was always so close I stopped... the only exception with the Hornady tool method is it’s hard to get consistent measurements for 5R rifling, for 5R I use the stripped bolt method. Just my 2cents...

 

[Dusty Stevens]

That video that @Alex Wheeler posted is the quickest and most repeatable method not to mention the cheapest. It works on any case, any bullet anytime no matter the freebore or wear. Im glad he took the time to unselfishly make it

 

[KenOath]

That video that @Alex Wheeler posted is the quickest and most repeatable method not to mention the cheapest. It works on any case, any bullet anytime no matter the freebore or wear. Im glad he took the time to unselfishly make it

Yep the Alex Wheeler method is what I’m referring to when I say stripped out bolt method, great vid I’m glad he shared it also..

 

[Drop Port]

Looks like I’m in the minority here but I don’t have any problems finding a consistent lands measurement with the Hornady tool and Sinclair Stainless Steel insert, can always get within a couple thou... use to double check with the striped out bolt method but was always so close I stopped... the only exception with the Hornady tool method is it’s hard to get consistent measurements for 5R rifling, for 5R I use the stripped bolt method. Just my 2cents...

5/16x36 tap, thread you own fire formed case and stand the rifle vertical you can feel the weight of the bullet and feel the touch, very consistent.

 

[JFrank]

I believe knowing for sure you are off or in the lands and maintaining a reference point is what is important. Granted, you want to know fairly close as to where you are - as the pressure spike needs to be anticipated when going deep - and you also want to know you are clear of the lands by at least .003" once out. Whether you are .002" or .005" off one way or the other matters little - it is how the gun reacts to the position you are in and making adjustments from your reference point.

I

Looks like I’m in the minority here but I don’t have any problems finding a consistent lands measurement with the Hornady tool and Sinclair Stainless Steel insert, can always get within a couple thou... use to double check with the striped out bolt method but was always so close I stopped... the only exception with the Hornady tool method is it’s hard to get consistent measurements for 5R rifling, for 5R I use the stripped bolt method. Just my 2cents...

Looks like I’m in the minority here but I don’t have any problems finding a consistent lands measurement with the Hornady tool and Sinclair Stainless Steel insert, can always get within a couple thou... use to double check with the striped out bolt method but was always so close I stopped... the only exception with the Hornady tool method is it’s hard to get consistent measurements for 5R rifling, for 5R I use the stripped bolt method. Just my 2cents...

my new chamber was a little tricky at first, but now it's no problem getting a repetitive number that I call lands.

Do we really need to find the lands to the .001 of an inch or do we really just need a datum to start our seating test from. i know many have an unreasonable fear of jaming bullets but on my target rifles i always start load development jammed .010 or .020. That distance to the lands is a moving target anyway.

i use the stoney point and after years of practice can get consistent measurements easily to .002 or .003. My thoughts are that is plenty good for a starting point. I find that with a new barrel after 100 or 200 rounds with a well broken in throat that measurement is quite different and than it settles down.

yes , mine took about 75 rounds to get the rough off , now 107 smk slide right in and stop plus or minus.001-2 I write that CBTO number on the box as well as BBTO that's my benchmark for my ladder test and seating depth.
As I mentioned earlier after dbl checking a new box (with the same lot number) they weigh the same BBTO was the same but my rifle said nope! Not the same..
I set them aside for future study.
J

 

[KenOath]

5/16x36 tap, thread you own fire formed case and stand the rifle vertical you can feel the weight of the bullet and feel the touch, very consistent.

Yep I get my smith to thread my fired cases, then I size the body and shoulder like I normally would for that chamber and good to go...I haven’t tried standing the rifle vertically but will give it a try. Cheers

 

[KenOath]

I


my new chamber was a little tricky at first, but now it's no problem getting a repetitive number that I call lands.

yes , mine took about 75 rounds to get the rough off , now 107 smk slide right in and stop plus or minus.001-2 I write that CBTO number on the box as well as BBTO that's my benchmark for my ladder test and seating depth.
As I mentioned earlier after dbl checking a new box (with the same lot number) they weigh the same BBTO was the same but my rifle said nope! Not the same..
I set them aside for future study.
J

Just takes a little practice to get a feel for it.. but I did find it good to check my numbers with the Wheeler method.