.223 Bullet Seating Depth Ladder Structure Needed

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peeplwtchr

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Hi All-

I now have basic loading down (Per manuals) for 9mm and .223, and am looking to start tweaking seating depth on my best .223 nodes.

I determined that my distance to the lands is COAL 2.349 OGIVE 1.930, using the method below, where I use a dremel to cut a case neck: .

I have read that I should start .015 thosandths off the lands, then seat .003 deeper with each ladder step?

I am seeing many methods, but couldn't find anything here, which I trust most. What is your process?

Thanks
 

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Seating length test is done after I found my optimum load. I normally start at 0.020" and test going in and out. Some bullets prefer a long jump. Are you shooting these in bolt or simi? The last test is trying different primers.

Just remember unless your doing a Jam your shooting at a moving target.
 
Seating length test is done after I found my optimum load. I normally start at 0.020" and test going in and out. Some bullets prefer a long jump. Are you shooting these in bolt or simi? The last test is trying different primers.

Just remember unless your doing a Jam your shooting at a moving target.

Thanks, shooting from a semi.. What increments after .020 do you do?
 
Last soft jam i did was with a Honady .224" ELD 75gr and was .196" longer than Hornady's recommended length so I just seated to Hornady's length and started from there. From there I moved.010" out and .020" in deeper and did not see any significant difference. I have tried the same with a Hornady 62gr and once again seen no real change. So maybe it's just me.
 
If this is just for target shooting and you can load one round at a time or your not worried about having to eject the round without fireing, then you can seat to the jam length or even 0.010 longer depending on your chamber. If you are using this for hunting and you need to be sure you can extract a live round, then 0.020 from jam length is a safe starting point and then 0.003 increments.
 
What firearm and what is the end goal?

Some things you can do with certain types are not a good idea with other types, or not even possible. If the goal is to come up with a decent load for lots of different rifles, in the caliber, stay on the beaten path.
 
What firearm and what is the end goal?

Some things you can do with certain types are not a good idea with other types, or not even possible. If the goal is to come up with a decent load for lots of different rifles, in the caliber, stay on the beaten path.

Thanks, I am looking to find a load for 2 different 1:7 18" barrels. I am close to .75 - 1 moa now, looking to get a common load that is .5 moa or better if possible. I don't want to load a different recipe for each rifle if I can help it.
 
Starting with the current depth your using, seat the bullet incrementaly towards the lands until the rifle goes OUT of tune than repeat the process away from the lands until the rifle goes OUT of tune.
I like increments of .003
 
Jam is a technique used most effectively in bolt guns with vld style bullets. Some even soft seat with near zero neck tension. Please dont try this in a semi
So just to make sure my terminology is correct, the Jam test is the max COAL technique I used, and posted the video about right?
 
Yeah I should have been more specific. Jam minus 0.020 as a starting point and then minus 0.003 increments from there. Or as mentioned, start with max allowed by mag length if this is less than jam and go minus 0.003 increments from there.
 
Chances are in an AR unless you have a custom reamed barrel, which it doesnt sound like you do, you will load at .2.255-2.260 or 2.300 if you have long COAL SSTL mags. Its pretty much a given that you want to run at Mag length, but I have seen increased jump increase accuracy a little, but we are only talking about seating 10 thou deeper at 2.250 or 2.245 COAL. Anything less than that has never yielded good accuracy for me.
 
Shooting in an AR you're pretty much married to mag length unless you're wanting to single feed. Some mags can do about 2.300" instead of the normal 2.260". You're going to be a ways from the lands, it looks like about .090" of jump if you go with 2.260". The 75's and 77's that are made/designed for mag length are pretty jump tolerant. I'm jumping about .110" in my 20" .223 with 77smks and it'll consistently do 1/2-3/4 moa with it's favorite loads.
 
Thanks, shooting from a semi.. What increments after .020 do you do?

I jump any where from 0.003"-0.005". In my AR's I have been able to tune some loads ( the cheap Hornady 55gr FMJ-BT) so all my guns shoot the same load with just a small tweek on the OAL. Most of the time I only have to move 0.005". I had to do this with different years of my LC brass, 223R. Some years I was able to mix, some not. The advantage I have is I cut all of my chambers with the same reamer, head spacing them all the same.
 
I jump any where from 0.003"-0.005". In my AR's I have been able to tune some loads ( the cheap Hornady 55gr FMJ-BT) so all my guns shoot the same load with just a small tweek on the OAL. Most of the time I only have to move 0.005". I had to do this with different years of my LC brass, 223R. Some years I was able to mix, some not. The advantage I have is I cut all of my chambers with the same reamer, head spacing them all the same.
Do you know what the inconsistency in LC brass was? Case volume? I use LC exclusively.
 
I started jumping .010 to .015 in my Dasher with Berger 105 Hybrids and a brand new barrel, and it shot 1/2 MOA quite easily, often under. I have not chased the lands and after 1700ish rounds it still does.

This is two three shot groups after cleaning the last time to foul the barrel. I had six rounds leftover from the last match.

From the bench, Atlas bipod up front, Pint Sized Game Changer in the rear, kneeling on a folding chair.
Fouling Barrel After Cleaning - 6 Shots @ 45%.JPG
 
shooting from a semi..

Shooting a Semiauto, don’t sweat the small stuff. You’re not competing in registered BR matches, so don’t let yourself get distracted here.

There is nothing in God’s heaven and earth, after building and rebuilding LITERALLY hundreds of AR’s for the last 20+ years, which could convince me to ever mess around with jamming bullets in an AR. Dumbest suggestion I have seen in a long time.

Frankly, almost all of the AR’s I have built in the last ~15yrs have shot sub-MOA, and I haven’t done ANY seating depth tuning for any of them for at least a decade.

I also haven’t done seating depth testing nor adjustment as my throat erodes in my PRS rifles for the past 3 years. My 6 creeds have fired sub-half MOA groups reliably from 5 thou off to 140thou off...

Moral of the story, so very, very, VERY much about load precision depends on something other than seating depth. To the point that - even as a precision rifle competitor spending thousands and thousands of dollars per year in competition - I don’t even bother with seating depth tuning...
 
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