Bullet seating

BoomFlop

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Oct 16, 2012
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Wisconsin
The Nosler Ballistic Tip 40 gr has a variance in my lot by .012 to ogive and much greater oal in the 70 or so I checked.
 

memtb

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Dec 30, 2013
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Winchester, Wy.
I seat it, lift the handle slightly and rotate cartridge slightly 1/4-1/2 rotation and seat again. Don't know if it matters but thats how I dow it. I wouldn't worry about that one or two thou yet, it'll be fine. You are splitting hairs for a load that you dont even know will work yet. Go out and shoot them, get the cases fireformed then worry about the fine details. Once I know they fit in the magazine and feed properly I dont care about the OAL measurement (only CBTO)

Exactly the way I’ve been doing mine for quite a few years! I think that it helps with OAL consistency but possibly with bullet concentricity. It may be just a “feel good” thing.....but, it makes me “feel good”! ;) memtb
 

Nimrodmar10

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Aug 21, 2011
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Lynchburg, TN
I am using a Redding VLD Micrometer Seating stem....that is what Redding advised for me to get for Ballistic Tips, Vmax and Amax type bullets.
You still need to make sure the bullet tip isn't bottoming out in the seating stem, and that it's not binding on the bottom edge of the stem. It should seat into the stem on the ogive
 

Nimrodmar10

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Aug 21, 2011
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As long as the ogive is in the same place on the bullet. I've seen as much as .025 difference in different lots of the same bullet.
Some manufacturers bullets are more consistent than others in the same lots also.
Different lots of bullets may vary on the length from the bottom of the bullet to the ogive. That's why I buy bullets in large quantities of the same lot. If they vary much within the same lot, you need to find a new bullet manufacturer
 

Varmint Hunter

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Dec 26, 2001
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3,207
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Long Island, New York
Checking every round as they come out of the seater die will show you just how much influence compressed loads have on CBTO measurement. It is one of the reasons that I avoid compressed loads when possible. Or .... you need to measure and adjust as Mikecr indicated.
 
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brguide

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Oct 13, 2013
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Globe, AZ
Get good dies and right seating stem for your bullets. Always measure CBTO being that COAL can vary. Here is the main key don't buy cheap calipers. I noticed with cheap calipers my bullets varied .002 but with a good 8" (since I shoot long magnums) calipers (Mitutoyo, Starrett, Brown N Sharpe) every case CBTO is exactly the same and the cheaper calipers were making it seem as if I had different lengths. Rotate the cartridge as you seat the bullet this will help with concentricity. A good press and dies will get you down on concentricity to .001 or less. I ended up buying a Harrell press and whidden dies out of everything I have tried these are the straightest I could get.
 

emp1953

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Sep 29, 2013
Messages
154
Hey

How does everyone seat their bullets?

Here is what I’ve done so far:
1)Seated bullet to OAL perfectly
2)Measure CBTO on that bullet and seat the rest
3)Check each bullet after seating

What I’m finding is that there are variables, I’m assuming in the bullet shape (40gr Nosler Ballistic Tip)

So do I go back and get them all to the same CBTO or Micro adjust seater for each bullet? For example seat cartridge 1, then back seater off and seat cartridge 2 and repeat?

Thanks
Steve
I use a single stage Rock Chucker press. I drop powder charges to within 0.5 gr or so of desired then trickle up to the exact weight. I get one round done perfectly, measured with a dial caliper. Then I proceed to process 49 more rounds. I check concentricity on each round, and I check the length of each with the dial caliper. It takes longer to get things done, but when I take that shot and miss the only thing I can question is the jerk behind the trigger.
 

misterc01

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Feb 15, 2019
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288
Location
Florida Panhandle
I have found that seating the bullet, then turning the round and a second seating helps with concentricity. When done with them all, I then check each round for concentricity and adjust as needed with a Hornady Concentricity Gauge. I accept .002 or less. So far, that works for me.
 

Nimrodmar10

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Aug 21, 2011
Messages
954
Location
Lynchburg, TN
I have found that seating the bullet, then turning the round and a second seating helps with concentricity. When done with them all, I then check each round for concentricity and adjust as needed with a Hornady Concentricity Gauge. I accept .002 or less. So far, that works for me.
Do you use a good quality in-line bullet sweater? If so, and you're having concentricity problems, you may have other problems
 

waveslayer

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Joined
Apr 9, 2012
Messages
239
Location
San Juan Capistrano, CA
Like others have said, OAL means squat! I always use the comparator , that will give you considerable more accuracy. I point bullets as well so I always use a comparator and renamed it COAL for Comparator Overall Length for my own personal data.
 

Savage 12BVSS

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Dec 20, 2019
Messages
526
Location
Maine
If your checking at the Ogive, they should all be the same at the point that matters.
That's the deal, its not overall length its finding your OAL where the bullet hits the lands, and setting your seating die and not worrying about individual cartridge lengths. The Ogive is part way down the bullet and is where your seater is locating on. Once the seater is set lock it down and load all your rounds to same distance off lands.
 

Mc Fraser

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Jul 23, 2018
Messages
194
Location
Calgary, AB
I don’t know if it was suggested but I would check the bullet (not cartridge) CBTO. The inconsistency might be from bullet CBTO variance. Then I will question the way you operate the press and then the die itself.
I had the same issue and it was the die. I used Redding and switch to Forester. There’s nothing wrong with Redding dies, mine was off and Redding wouldn’t even respond my emails after I show proof. Usually Redding and Forester make really good dies. I would question myself before I question the die.
I hope this helps.
 

wonderman4

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Joined
Oct 7, 2013
Messages
109
Location
South Texas
Not to be snarky and certainly not to PO anyone, but it should be BBTO (bullet base to ogive).

I measured 100 Accubonds to get a handle on the ES of the BBTO.

they were 30 cal 150 gr.

The variance surprised the crap out of me. Only 0.003" ES measuring 100 bullets.

Good enough for me.
 
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