X" from the lands... How?

svt-40

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How do I determine how deep to seat the bullets in my Stevens 200 in .223?
I use several kinds of bullets all different length and different shape of ogive.
 
I'll explain the simple way I do it, but I expect more experienced reloaders have better ways (some of which unfortunately require more equipment!).

I will take a completely prepped piece of brass to which I haven't seated a primer, and seat a bullet to a fairly long OAL. I'll try to chamber it, and if it doesn't chamber, I'll seat it a little more. I'll keep on doing this until it chambers with difficulty. Then I'll rechamber it a couple of times, and after that I measure the OAL. This I take to roughly be the OAL that puts the bullet as just touching the lands.
 
Take a neck-sized case and with a dremel tool, cut a slit in one one side of the neck and then the other, the full length of where the bullet will sit in the neck. Push a bullet part way into the neck of the case and gently chamber it. Gently eject the case and measure. I would do this a few times to obtain a consistent number. This length is your "soft jam" or "kissing the lands"

I just saw an article on this last week but can't for the life of me remember wher I saw it. I should have bookmarked it. :bangHead:
 
There are commercial tools, of course.
Here is a homemade system. Take a rod that will slide through the bore. Make a pair of collars that you can lock onto the rod. Slide the rod down the bore until it is against the boltface. Lock the outer collar in place. Remove the bolt, push a bullet (projectile) into the chamber until it is seated in the leade. Keep it there. Place the end of the rod against the bullet nose, slide the inner collar against the muzzle, lock it in place. Measure the distance between the collars. That will give you the length of a round with the bullet seated to contact the lands. This method will produce accurate, repeatable results. Now, there is a catch. Not all bullets are identical, and you are measuring to the tip; the measurement from the tip to the ogive can vary slightly. But the measurement generated will be within a few thou. for a given lot of bullets.
 
Take a fired case. Put a bullet in it. Use a lighter to make the bullet nice and black with smoke.

Gently chamber the round, and then ever so gently extract it.

You should see marks on the smoke where the lands touched the bullet. If so, measure the OAL, that that's your length to the lands.

If not, pull the bullet farther out and repeat.

Edited to add: you will have to do this for each type of bullet, as ogive length varies quite a bit from on to the other.
 
Take a neck-sized case and with a dremel tool, cut a slit in one one side of the neck and then the other, the full length of where the bullet will sit in the neck. Push a bullet part way into the neck of the case and gently chamber it. Gently eject the case and measure. I would do this a few times to obtain a consistent number. This length is your "soft jam" or "kissing the lands"

I just saw an article on this last week but can't for the life of me remember wher I saw it. I should have bookmarked it. :bangHead:

I saw it too, on Mystic's page I'm pretty sure (????) neat trick, haven't had a chance to try it yet.
 
Tiriaq's method gives 2.174
A few loads for the same bullet from the handloaders' sites recommend 2.171".
But I can chamber a 2.24" or even 2.26" round with the same bullet without it pushing the bullet further down. Why?

Also, I tried loading for Barnes 70gr triple shock and found that I can't put more than 20gr of IMR4064 into the cases. Their starting load is 19 and maximum is 23.7 but that would be a very compressed load. Is that safe?
 
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Get yourself a Bullet Comparator. It measures from the base of your case to the ogive of the loaded bullet so your COL from Base-Ogive will be consistent rather than measuring from Base-Meplat which can change between different bullets.
 
Here's a picture of the tool Cyan1de is talking I got one for every caliber i reload.

Lenghtgauge.jpg


This is easy to do just experiment with old full lenght resize, unprimed brass.

Cheers
Gaetoune
 
My system that requires no specialized equipment, other than a dial caliper, is as follows -

Seat a flat based bullet with parallel sides backwards in a sized, unprimed case. Chamber the round without slamming the action closed. This will give you an accurate length from the bolt face to the lands.

Take you bullet of choice - press it nose down into the muzzle of the rifle barrel, and turn it - this will scribe a line where the bearing surface matches the bore diameter.

Now because you know the distance of the lands from the case mouth, you can measure the distance from the case mouth to the bearing surface, and seat your bullet at whatever distance you like off the lands.
 
Silverado's method has always worked for me. With any spitzer type bullets I've tried in my Abolt 7-08, the magazine has determined max overall length. Only the Hornady 154gr round nose would touch the lands and had to be shortened.
 
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