Equipment & Gear > Guns and Ammo

Bullet Seating Depth

<< < (5/9) > >>

high country:
try loading some tsx's at .08 to .125 off.....see what it does for you. scirroccos can't do that they are too long and seem to like to be close to the lands.

JLS:
I load my TSXs just short enough to fit in the magazine and have had very good luck with that.  Am I missing something here, because with my M70s I cannot seat right off the lands and still have the cartridge fit in the magazine?

high country:

--- Quote from: JLS on March 16, 2011, 09:14:26 AM ---I load my TSXs just short enough to fit in the magazine and have had very good luck with that.  Am I missing something here, because with my M70s I cannot seat right off the lands and still have the cartridge fit in the magazine?

--- End quote ---

spend 3 bullets and try what what I said^^^^^^

sakoshooter:
After reading that link Killbilly posted all the waaaaaaaaaaaaaaay to the bottom I put a few ideas together that I'd read on it and came up with this:
I'll word this the way I did it and you guys can adlib from there. Or PM me and I'll give ya my phone number.
To establish C.A.O.L.(case over all length) and/or seating depth with each bullet I'll ever use, here's what I did.
1) Put my gun in my cleaning rest on my reloading bench. Bolt cocked(gun empty of course)and closed. No protruding firing pin if it's cocked.
2) Using a wood dowel(long), small enough to fit down the barrel, insert it untill it touches the bolt face. Using a razor blade, make a slight cut/mark on the dowel exactly flush with the end of the muzzle.
3) Remove the bolt.
Both dowels could be the same diameter. Match the caliber.
4) Insert another dowel(short) (just small enough to fit into the bullet recess area of the chamber) into the chamber from the breech end with each bullet  you're going to use. One at a time of course. It takes a little finageling sometimes as some bullets want to slip into a bolt lug recess. Using the dowel from the muzzle end at the same time helps align the bullet so it enters the chamber correctly.
Anyhow, slowly slide the bullet into the chamber using the short dowel with your left hand while sliding the other dowel down the barrel from the muzzle end with your right hand untill the long dowel contacts the tip of the bullet.
Note: It's easy to push the bullet into the lands so be very gentle and use the same force on each bullet for a consistent measurement.
Remember that your bolt face measurement is already established and will be the same for all measurements with that particular gun.
I pushed the bullet off the lands a few times with my right hand dowel while pushing it back against the lands with my left hand dowel at the same time untill I was satisfied with it just barely making contact.
5) Now, slightly lift up on the long dowel to put pressure against the muzzle so the dowel won't move while you're reaching for the razor blade you forgot to set close enough to reach, LOL.
Providing that the dowel is still exactly in place against the bullet tip  and the bullet is barely touching the lands, make another cut or mark with the razor blade flush with the muzzle.
6) Remove the long dowel and using a reloading micrometer(knife edge), measure the distance between the two cuts. I used a fine point pen to make the cuts easier to see.
The resulting measurement(write it down)is the C.O.A.L. for THAT bullet TOUCHING the lands. Rember that this measurement is Touching The Lands. This might not be a safe seating depth for some established loads as greater chamber pressure will result with a bullet seated against the lands. Most of you already knew that but thought I'd better say it.
Based on a posting from Sinclair International stating that they'd found the 'sweet spot' to be between .020 and .030 off the lands with most guns/bullets, I adjusted my seating depth to be .025 off the lands based on all the new measurements I just took. My rifle magazies will allow this. Yours might not. Check it out as your magazine might be the determining factor for COAL.
Each bullet will extend into the lands differently, so rotate the dowel and make a new mark for each bullet you have on your bench.
I did this and wrote down the COAL for each cal(3 rifles)and 13 bullets. I then subtracted .025 from each measurement and am going to use this as my new starting point for working up loads. I recorded all of it so I won't have to do it again unless I try a different bullet.

Over the years I've always used a felt tip marker to color a band around a seated bullet right at the ogive, chamber it, re-seat it again and again untill no marks appeared from touching the lands. I established 'dummy' rds for most bullets over the years but really never knew exactly how far off the lands I was with any given bullet untill now.
Upon checking out some of my dummy rds that I thought were barely off the lands, surprise!! They all varied considerably. I adjusted them yesterday with an enertia bullet puller and re-seated them to my new COAL based on my new findings.
It's actually really easy to do this and now I know exactly where each bullet is seated and can use a micrometer to double check each time.

quadrafire:
Good post. I am new to reloading, but I have 3 calibers at this time that I am working up loads. This sounds pretty strait forward. You described it well enough that even a dummy like me could do it.

Navigation

[0] Message Index

[#] Next page

[*] Previous page