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Obmi
09-05-2016, 11:56 AM
Im loading some 30-06 but I'm not sure about the C.O.A.L. for this bullet. Im using Lee Precision C312-155-2R Double Cavity Mold. But Im using the layman cast bullet handbook 4th edition. I will be putting them through a Lee .309 sizing die. But the over all length is different for all the Lyman models listed. I plan on using the load data for the 150gr round and working up. its for Lee #C309-150-f Starting IMR-4198 24.5 to 35.5 max (That's ok right?) it has a C.O.A.L. of 2.984 oal.
If I understand stuff correctly SAAMI spec is OAL 2.940min and 3.340 max. as long as i'm in that range in ok and get to keep my fingers right?http://www.saami.org/pubresources/cc_drawings/Rifle/30-06%20Springfield.pdf


This will only be shot out of a savage axis bolt rifle in 30-06

I have confused my self.

JSnover
09-05-2016, 12:01 PM
The COAL usually changes for different nose profiles and boolit weights but as long as you're in that range you'll have nothing to worry about.

Shiloh
09-05-2016, 12:07 PM
That boolit is not near long enough to cause and issue. My guess is, there is lots of room before you even begin to fill the throat.

Shiloh

OptimusPanda
09-05-2016, 12:16 PM
You could take a fired case (assuming it was originally fired in this rifle), resize it so that only the top of the neck is sized back down, barely seat your bullet on it, and slowly ease it into the rifle and close the bolt. It'll give you the absolute longest you can be since the rifling will seat the bullet deeper in the case until the bolt locks.

JonB_in_Glencoe
09-05-2016, 12:17 PM
I believe that boolit has a tapered nose? I have the 160gr. which has the tapered nose...ANYWAY, for all my bolt gun loading, I seat the boolit to engage the lands...every rifle may be different. I make sample/dummy rounds, and cycle them in the gun, to check for function as well as OAL, judging by witness marks on the boolit.

edit: anyway, no worry about pressure, with Lyman's cast boolit data, it's much lower than Max SAAMI pressure for any given cartridge. but it's always good to double check SAAMI specs, to Lyman Data (pressure).

JSnover
09-05-2016, 12:23 PM
At 155gr, the OP is loading a fairly average boolit length. Using very light or very heavy boolits (very short vs. very long) there might be issues.
Waaaay back in the early days I thought it would be cool to load 110 RN (.30 M1 carbine) bullets out far enough to touch the rifling in my 30-06.
I laugh about it now.

Obmi
09-05-2016, 12:47 PM
Is that dangerous or just ineffective? Im not sure what you mean.


At 155gr, the OP is loading a fairly average boolit length. Using very light or very heavy boolits (very short vs. very long) there might be issues.
Waaaay back in the early days I thought it would be cool to load 110 RN (.30 M1 carbine) bullets out far enough to touch the rifling in my 30-06.
I laugh about it now.

Obmi
09-05-2016, 12:53 PM
I just don't what it to be dangerous. I have always used hard copy data and have never worked up a load with out the exact bullet in the data. Some were ( I dont know where) I head seating to deep or to far out can greatly increase the pressure and cause a Kaboom.
I could be wrong ( or just stupid) but The seating depths is about chambering and accuracy? and the book data is about it working in most all guns.

This is the load data.
175903

T175904his is the lee rifle molds

rintinglen
09-05-2016, 01:29 PM
Even if the chamber pressure increases 15 percent due to you altering the seating depth, as long as you start at the starting load, there would be no safety issue.
Starting loads are deliberately kept light to provide a safety margin for that one in a thousand gun that manages to pile up all the possible variables in the worst possible direction.

I don't use that boolit, but I do use the 311-466, a similar length 155 grain rn boolit, loaded to a COAL of 3.00". Two Loads that have worked well are 25 grains of SR-4759, and 26 grains of 5744. Another good choice is 32 grains of IMR 4895. These are all light loads in the 1800- fps range.

Hardcast416taylor
09-05-2016, 01:47 PM
Your fear of causing a `KABOOM` (your term) about having the boolet engaged in the rifling is pretty groundless due to the softer nature of lead over that of a copper jacket that can cause a `Kaboom` if seated excessively far out into the rifling.Robert

JonB_in_Glencoe
09-05-2016, 01:57 PM
You can't get into trouble, varying OAL to fit your savage factory rifle, using those lyman listed powders at starting loads...and working up, til you get accuracy...but you should always check for over-pressure signs as you work your way up.

you don't mention what alloy you are using...but for best accuracy, it's best to match alloy hardness to Pressure of the Load. Some maximums of that are listed in this very informative link.
http://www.lasc.us/CastBulletNotes.htm

Generally, I load 30-06 in the 25K to 30Kpsi range, with a alloy like 94-3-3, which is fairly similar to COWW. Which is way below the 60Kpsi SAAMI Max. IF you want to speed things up to near j-word velocities, you need a much harder alloy, besides other things.

Obmi
09-05-2016, 02:01 PM
Lyman #2 water quenched lead Harbor freight red powder coated. I haven't sized or added gas checks yet. I was going to start low and look for over pressure and each step.
Probably make 5 rounds at a time then test and inspect the chase for over pressure As a bonus I have a endoscope for my phone so I can really check out the bore or look inside the cases.
175907

clum553946
09-05-2016, 02:06 PM
You might want to consider AA 5744 for reduced loads. It's not very case position sensitive & the Accurate Arms website states it's ideal for low density reduced loads in bottleneck rifle cartridges. I use it for reduced 45-70 Trapdoor loads whereas I use a dacron filler if I'm using IMR 4198.

Yodogsandman
09-05-2016, 03:58 PM
Is that dangerous or just ineffective? Im not sure what you mean.

It's humor! You can't seat one out far enough to reach without it falling out of the case.

You might be in the same situation. That boolit might not seat out far enough to touch the rifling.

I'd seat it so it looked right in an empty case and try it in the chamber, looking for marks on the boolit nose. Then adjust if needed.

Start at the starting loads with any powder charges, working up only after I knew they were safe. Work up higher loads slowly, looking for any signs of excessive pressure. Don't fully trust any books or internet sources. Check for yourself.

Tom W.
09-05-2016, 05:09 PM
If it fits the magazine....... I shoot a 30/06 A.I. single shot and load it as long as I can.

retread
09-05-2016, 05:26 PM
Have you slugged the barrel on that 06. I have had better luck sizing to .311 but then I might have a bigger bore than you. Nice thing to know.

RU shooter
09-05-2016, 05:58 PM
Make up a unloaded dummy round ,start out on by seating till the case mouth is in the middle of the top drive band . See if it will chamber easly if it does you can't seat it out much further all you'll have in the case neck is the bottom drive band and the gas check , if it does chamber hard seat it deeper till it barely touches when you close the bolt or just a smidge back from touching anything . There's no stead fast rule for COAL with cast bullets long as it is short enough to to fit in the magazine and chamber easily

JSnover
09-05-2016, 06:07 PM
Is that dangerous or just ineffective? Im not sure what you mean.

Not dangerous at all. The case mouths were just barely long enough to seat the bullets... by the time I got to the range half of them had fallen out.

Obmi
09-06-2016, 02:15 PM
I was having a heck of a time getting the bullet seated in the dummy round. But I got it. In hind sight I could of used a fired case. That way I could of put the bullet in by hand and closed the chamber on it. I think I will do that with a fired case before I mess with it. I'm going to the range Saturday anyway to sight in the scope.

Thanks guys for all your help. Im going to re-read the first 1/3 or so of the Lyman cast bullet book.

varmintpopper
09-08-2016, 05:04 PM
Here is a way to measure:

1. Drop a wood Dowl down the barrel until it rests on the closed Bolt Face.

2. Mark the dowl at the muzzle, (I use a razer blade laid flat on top of the barrel.)

3. Open the bolt, Put the bullet You'll be loading into the breach and gently push it against
the rifling, (I use a pencil with eraser for this.) Hold the bullet firmly in place.

4. Slide the Dowl into the barrel until it rests on the nose of the bullet, Mark the Dowl at the muzzle again.

5. Use Calipers to measure between the two marks. This measurement is the Maximum Cartridge overall length
for that bullet used in that gun.

If You would like Your bullets to be 10/15/20 thousands or so off the Lands and Groves then subtract that amount from the measurement,
And make that Your Cartridge overall length. ( do this a couple times just to make sure Your doing it right)

Good shooting

Lindy

Hamish
09-08-2016, 05:21 PM
Obmi,

Something to consider,

SAAMI drawings and specs are all fine and good, but do you think every (any?) chamber gets cut exactly to to spec? What about chambers cut before there was an accepted spec? Military and older rifles with eroded throats? I don't believe there is such a thing as holding two of the same gun and them having identical chambers. Close maybe, but not identical.

My point is that I consider published COL a ball park starting point. New bullet/gun or both? Start with a dummy seated out as far as I think I want to get away with and start test fitting it in the chamber and go from there.