Land marks on bullets

[500x]

With my stoney point tool, it gets my seating depth close, but getting variable readings, im close now, someone please tell me aprox, how far in the lands I am with a square marks and with rectangle marks, about twice as long as wide.

Thanks in advance

 

[rocketron]

use a size/ unprimed case......seat your bullet and check for marks...measure it with a comparator..then start seating it deeper by .002 till you get no marks...at this point you will know how far in or out of the lands you are..

once you do this it is easly repeatable to get your seating depth back on track when you get erosion.

it also helps to polish the bullet with steel wool to get rid of the old marks and make the new marks visable.

Ron

 

[whiskey08]

you can also try barely sizing the neck, and letting the lands push the bullet in, then measuring with a comparator. With the right amount of neck tension ive always been able to find the lands. Ive checked with a stoney afterwards and was suprised to see that the stoney was seating further into the lands.

 

[500x]

. Ive checked with a stoney afterwards and was suprised to see that the stoney was seating further into the lands.
[/quote]

Yep, this is the problem I'm having.

 

[Bulseyetom]

I mark my bullets with a brown Sharpie to see the land marks easier. I seem to have best luck seating a bullet well into the lands, then seat it deeper in the small increments like suggested above until the marks just disappear. Using the marker makes it easier to wipe the markings off and try again. Obviously seat the bullet into an unprimed case. Tom

 

[rocketron]

i use the sinclair seating depth tool and it's always been within .003

i think the problem with the stoney is if the case don't have the same headspace as a sized case you'll be off......but you should be able to add or subrtact the difference and be closer

Ron

 

[500x]

Thanks for the info guys, rifle shoots well with square marks on the bullet, I think im pretty close to .010, I was just looking for a number, I had a couple of old timers that know a lot more than I do tell me that square marks mean .010 in and rectangle closer to .020"....I think, I just can't remember exactly, it's been a while.

 

[gilream]

rocketron...excellent observation. Took me a while to figure this out some years ago. The modified cases that come with the stoney point tool have a different, sometimes way different, headspace than your fireformed cases. If you measure the stoney modified case with your headspace tool and compair it to the headspace measurement of your chamber fired cases there usually is quite a difference. (The stoney case will almost always be longer than your fireformed cases.) Usually if you add that difference to your stoney measurement you will get a Lands Engagement Point reading that is very, very close to the reading you get from the above mentioned method of bullet seating a little deeper each time to find out where the rifling marks first dissappear. Before they were bought out, Stoney Point would make a custom modified case from your fired case if you sent it to them, but why do that if you can just measure it.