30-06 and COAL

[DeadFlies]

I recently pulled 60 Sierra 125 grain Pro-Hunter JHP/FN bullets out of 30-30 cases so could use them in my 30-06. Not the best bullet choice but, it's what I have on hand right now.

The load data that I have from Lee states that a 125 grain jacketed bullet loaded with H4895 should have a (MAX load) COAL of 3.170.

That's waaaaaaay too long.

With the bullets seated to the middle of the cannelure (which is about .308 inches; one caliber) a loaded round measures 2.90 inches.

I surmise that the rather generic information Lee provides is for longer, pointy bullets. One look at Sierra's site shows that the 125 grain FN is much shorter than the 125 grain SP.

Recommended COALs are to make sure bullets are not seated too deeply, thereby sticking too much bullet into the case and increasing pressure, yes? So the part that sicks out of the case, with regards to pressure, should be irrelevant?

Am I just asking for a trip to the ER or am I right on this one?

BTW I loaded these with 45 grains of H4895 (About a 15% reduction from MAX load) partly to ease my mind about pressure and length and partly because these bullets are made to work at lower velocities.

 

[YunGun]

You are correct about the COAL & the Lee data; they just compile & re-publish data from other sources and generally don't even reference the various nose styles.

According to my Lee 2nd Ed. 48gr H4895 (@2977fps) is the suggested starting load for a 125gr jacketed bullet so you're well within safety limits, & probably somewhere around their max intended velocity range of 2500-2600fps.

 

[Coltdriver]

Why don't you figure out what your rifle chamber will take? It takes very little effort to determine what your chamber measures.

I have found that each chamber is slightly different. Measuring your chamber using the bullet you are going to load lets you seat the bullet at a known distance from the lands.

I used the book col on a .243 and found myself stuffing the bullet into the lands, turns out that the chamber I had on that particular rifle came with a very short throat. From that day forward I have always figured out the correct col for the bullet I intended to load.

You will be surprised at how far off most of the book data is when compared to the unique configuration of your chamber.

 

[dmazur]

As stated by others, the bullet profile is what it is all about.

What you said about increasing pressure by seating too deeply is very applicable to pistol cartridges and less applicable to rifle cartridges, due to their increased volume.

A dangerous overpressure can also be created to seating the bullets too long, so the ogive jams in the lands.

There are special tools to make determining seating depth easier, but you can create a dummy round with the bullet you intend to use seated deliberately too long to chamber and then just seat it deeper until repeated trials show the bolt will just close, with some effort.

Then seat it another 0.015" or so to clear the lands and allow for some variation in bullet manufacturing.

The cannelure may be a valid guideline for .30-30, but your .30-06 chamber may not have the same throat.

I would use a trial and error technique, such as described above, and ignore the cannelure. Also skip crimping...

 

[NCsmitty]

I understand your concern, but it isn't anything to worry about. If you seat the Sierra FP bullet to the base of the cannelure, it should be fine. Do one and check it in your rifle to make sure it clears the rifling, and doesn't mark the bullet.
That 125gr is a bit soft and will likely fragment like a varmint bullet at '06 velocities, but will be a fun load to shoot if it's anywhere near accurate.


NCsmitty

 

[Haxby]

Seat to cannelure, 45 gr 4895, good to go.

 

[gamestalker]

As for your powder charge, I have never personally found any good reason to reduce a starting charge, especially with high powered rifle powders. 125 gr. jacketed bullet data for 30-06 is the charge table to remain within. No further reduction is necessary and can actually create poor performance, or even damage your chamber due to gas leaks. This can lead to backed out primers, leaking primers, and damaging gas leaks due to the brass not sealing completely in the chamber. Lower than intended pressures can cause the brass to collapse at the shoulders and body as well, thus allowing hot gases to blow back through the chamber. If there is a concern as to that particular bullet, which is apparently intended for 30-30 velocities, not having the integrity to hold up to 30-06 pressures / velocities, reducing the powder charge further is not the solution.

GS

 

[Haxby]

Hodgdon shows a load of 40.5 gr H4895 with a 125 gr bullet.

 

[gamestalker]

I'm looking at Hogdon right now, and it is published as Sierra 125 gr. SP, H4895 48.0 grs. - 53.7 grs? That starting charge is 3.0 grs. under published start according to Hogdon reloading pages.

Maybe I missed something?

GS

 

[DeadFlies]

Thanks for the replies. I knew I would find a wealth of knowledge and advice this morning!

@ gamestalker - If I was using any other powder I might not reduce it that much but Hodgdon's website has a reduced load formula for H4895; apparently it works for this powder/bullet combo. I've used their formula for 30-30 loads and I have no signs of under-pressure or any other problems.

And 40.5 grains (That is what haxby is referring to) of H4895 is Hodgdon's reduced load charge for the 30-06 and a 125 grain bullet. So my recipe is a compromise between a reduced load and a starting charge, which sounds reasonable to me considering the bullet and COAL are both "off the charts", so to speak.

 

[DeadFlies]

you're well within safety limits, & probably somewhere around their max intended velocity range of 2500-2600fps.

That is exactly what I was intended to do with this recipe.

 

[USSR]

DeadFlies,

Ignore the cannelure. While it is necessary to crimp bullets used in most .30-30 rounds (which are typically used in tube magazines), there is no reason to crimp .30-06 rounds. Simply seat the bullets to a depth in which at least 1 caliber (.308") of the bullet is within the neck and be done with it.

Don

 

[steve4102]

Recommended COALs are to make sure bullets are not seated too deeply, thereby sticking too much bullet into the case and increasing pressure, yes?

NO. Not in a bottle necked rifle round. Seating deeper will decrease pressure, seating longer will increase pressure. Pistol rounds, yes, rifle rounds NO.

The OAL listed in the manual is not a requirement or even a recommendation, it is just there as a guide to show what they used.
Some manuals don't even list the OAL tested it is that un-important to the handloader.

 

[DeadFlies]

Simply seat the bullets to a depth in which at least 1 caliber (.308") of the bullet is within the neck and be done with it.

Don

That is precisely what I did. The cannelure is very close to, if not exactly, one caliber. So I seated to the cannelure and put a mild crimp on it to get uniform neck tension.

Easy Peasy.

 

[USSR]

I seated to the cannelure and put a mild crimp on it to get uniform neck tension.

Crimping does not give you uniform neck tension, in fact it can be disruptive of it. Uniform neck tension is the result of nearly uniform brass thickness in the neck as is typically found in Lapua brass or brass that has been neck turned.

Don

 

[gamestalker]

All you'll accomplish by crimping a bottle neck cartridge not intended for a tubular magazine or a machine gun, is shortened brass life span, and possibly impede uniform neck tension, as Don said. It also just complicates and introduces issues to the other wise simple process of seating bullets in a bottle neck cartridge.

GS