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 Consistent COAL
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arcticfern
Junior Member



67 Posts

Posted - Feb 19 2017 :  08:48:48  Show Profile Send arcticfern a Private Message  Reply with Quote
OAL.

Do better quality dies help with consistency in COAL. I am working up some .243 WIN loads. Brass has been prep and trimmed (all the same length). I am using Lyman dies.

I use a RCBS ogive tool to give me COAL, but my finished rounds very 2.225" - 2.235" (ogive measurement). 2.235" puts the rounds jammed into the lands....I want the rounds to stay consistent at 2.225"

.243 WIN
Hornady Brass
RL-19
Berger VLD 95gr
COAL Hornady ogive 2.225"

DUSTY NOGGIN
Advanced Member



USA
761 Posts

Posted - Feb 19 2017 :  09:18:14  Show Profile Send DUSTY NOGGIN a Private Message  Reply with Quote
is your shell holder making solid contact every time???

if you see any rings/indents where the seater plug is contacting bullet , you may need to modify your existing seater plug or change to a die that better fits the vld you are using so it contacts more of the bullet suface , i had a hard time not damaging amax bullets while seating because my seater was only contacting in a very thin ring , the amaxs seemed to be much thinner jackets

have you taken the seater out to see how well it fits the vlds

maybe brushing out all case mouths, trying to lower and equalize the pressure needed to seat

maybe belling case mouth slightly will help

then there is dry lube

fwiw , i had a very bad lyman die once , concentricity was way off ... maybe time for an upgrade

Edited by - DUSTY NOGGIN on Feb 19 2017 09:38:01
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Shastaboat
Advanced Member



USA
9124 Posts

Posted - Feb 19 2017 :  11:58:00  Show Profile Send Shastaboat a Private Message  Reply with Quote
Your bullets ogives are inconsistent. It has nothing to do with the brand of dies. It might be your bullet seating stem too. Try drilling out or boring the nose of the stem.

Edited by - Shastaboat on Feb 19 2017 11:59:40
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WonderMan4
Advanced Member

USA
2849 Posts

Posted - Feb 19 2017 :  12:43:29  Show Profile Send WonderMan4 a Private Message  Reply with Quote
Even match grade bullets can vary 0.005", maybe a little more.

Take your comparator and measure several bullets and see for your self.

Also, most seater stems will not contact the bullet at the ogive.
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Ireload2
Senior Member

USA
286 Posts

Posted - Feb 21 2017 :  00:13:55  Show Profile Send Ireload2 a Private Message  Reply with Quote
The important dimension is base to ogive where the bullet contacts the rifling.

The bullet can vary quite a bit from base to point but the point is not a functional feature except when it hits the end of the magazine.

To get an idea take the seater punch out of your die.
Color the tip of a bullet with a permanent marker. Then spin the nose of the bullet inside the seating punch and look for removal the marker ink.
You will notice the tip of the bullet never touches the punch. There is usually a band around the nose of the bullet about .100 to .125 down from the tip depending on the design profile.
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noylj
Advanced Member



USA
553 Posts

Posted - Feb 22 2017 :  00:57:46  Show Profile Send noylj a Private Message  Reply with Quote
If you are going to be anal about, and not simply measure bullets and factory ammo to verify that it really is NOT that significant, then you should have a separate single-stage seating press. Seat the bullet a bit longer and move to the other press and adjust that seating die in small increments until you get the COL that you want. Do this for every round.
I like to have custom seating stems made and have the seating plug ONLY contact the bullet as far down the ogive as possible.

Then said he unto them; But now, he that hath a purse, let him take it, and likewise his scrip: and he that hath no sword, let him sell his garment, and buy one.
Luke 22:36
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woods
Advanced Member

USA
2132 Posts

Posted - Feb 22 2017 :  21:44:01  Show Profile Send woods a Private Message  Reply with Quote
quote:
Originally posted by arcticfern

OAL.

Do better quality dies help with consistency in COAL.




YES

quote:
Originally posted by arcticfern

2.235" puts the rounds jammed into the lands....I want the rounds to stay consistent at 2.225"





Then you are seating TOO CLOSE to the lands. That last .010" from off the lands to touching lands has a large impact on velocity and pressure. IOW if you were seating .060" off the lands and your seating depth varied +-.005" then the pressure would not vary much. By contrast there is a large difference in pressure from seating .010" off and seating on the lands.

Best accuracy and consistency is often found much further off the lands than you think


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After Tuesday, even the calendar says WTF!

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Zero333
Advanced Member



Canada
811 Posts

Posted - Mar 01 2017 :  17:29:32  Show Profile Send Zero333 a Private Message  Reply with Quote
Measure the bullets base to ogive before seating them. Measure a sample of 25 to get a good idea.

If they vary by 0.003" then that's how much I would expect the Cartridge base to bullet ogive to vary.

If it varies any more than the measured sample, I would suspect the seating die's stem is not ideal for VLD bullets.


Treat that trigger like it’s your first date, not like you’ve been married to it for 20 years.
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bwalters99
Advanced Member



945 Posts

Posted - Mar 03 2017 :  16:07:52  Show Profile Send bwalters99 a Private Message  Reply with Quote
arcticfern...

A technique I use to maintain equal base to ogive length is by using Redding's Competition Seater Die in conjunction with a set of calipers and a Hornady ogive measurement tool on the calipers.

Before I first seat the bullet, I will dial out the die by about .005. Seat the bullet, take a measurement on the calipers to see how far off of desired base to ogive length you are. Once you know, you can then dial down the die to adjust for your desired length, then seat again..

This method, regardless of what you have found to be your ideal distance off the lands, will give you the same consistent jump to the lands, round after round.

As some of the others members have said, there are, and always will be inconsistencies in your bullets... shank length may differ, I've seen a difference of as much as .010 come out of the same batch. If you have that much difference in shank length and you're consistently seating the same base to ogive length. then the total length of bullet inside the neck will vary causing slightly inconsistent pressures inside your case. However small it may be, this could cause variances in your muzzle velocity, and as a result cause a shot to be higher or lower depending on it. I try to eliminate that by measuring the shank length, and sorting according to that...
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Tracy
Starting Member

USA
3 Posts

Posted - Aug 30 2017 :  13:47:34  Show Profile Send Tracy a Private Message  Reply with Quote
The author who suggested Hornady's OAL gauge tools & other tools is exactly correct, but depending on what tolerances you consider acceptable it isn't always perfect.
I'm a retired machinist, toolmaker, tool & die maker who's worked with extremely close tolerances "+.0001" or -.0001" on a daily basis. If you could divide a sheet of copy paper .004" thick into 40 equally thick sheets, one of those is .0001" thick.
I think Hornady's tool is great, but measurements are the only problem.
I load for & shoot bench-rest, but I don't compete. My fabricating background with close tolerances always plays into my reloading.
My rifle is a 22-250, with .250 diameter necked chamber. I have to neck turn my brass so a loaded cartridge measures .248" on the neck diameter. this gives me a total clearance of .002" around the neck when chambered in my rifle.
You would think the ogive to base measurement would always be the same. So did I. Well, it isn't always the same. For me, it normally varies no more than .003', but sometimes it's as much as .005". I've also noticed, even with Lapua brass, it doesn't always worked harden exactly the same from one case to the next. I know this because I use precision pin gauges to check the inside diameter of the neck on every fired case after bump-neck sizing the neck. I even use a nylon bore brush in a drill press to clean the inside of the neck. Doing all of this I still get a different fit on bullets as I seat them. It's only 4 or 5 out of 20 rounds that are like this.... sometimes 2 or 3.
I know a tighter fit won't release a bullet as easy.
Now you should know at the age of 76 years old, my eyes aren't always up to getting as good a groups as possible. Very thin crosshairs like on a target scope are useless for me.

On a final note..... The tighter the interference fit is between the bullet & neck ID there is, the more it's possible for the bullet jacket to deform. The more the nose of the bullet deforms , the longer the overall cartridge length will be simply because as it deforms it won't get pushed as far into the case neck.
The special seating dies available will minimize this some, but nothing is ever completely perfect.

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