Length for 30-06 loaded cartridge?

[FoghornLeghorn]

I'm loading some Nosler Ballistic Tip (Spitzer) 150 grain 30-06. (Starting load 55 grains IMR 4350.)

Nosler's website suggest 3.320 inches overall cartridge length for that bullet.

I've got some factory Remington 150 grain 30-06 PSP. They measure 3.1655 inches.

I have an Alliant manual that doesn't give data for Nosler 150 grain, but has the Hornady 150 grain Spire Point (that's Spitzer, right?) as 3.210 inches.

I have three 30-06 rifles. This is for a 2002 Remington 700 Mountain Rifle, and I've read that the bullet contacting the lands could create excessive pressures.

 

[Mike / Tx]

I have personally had great luck and accuracy from over a half dozen different 06's with H4350 and the Nosler BT seated to 3.250" base to tip.

I don't know why but all of the rifles really liked that length. As for the charge, it was usually worked up to be in the 56-57gr range.

I usually try to stay with a length that feeds easily from the magazine and some of the plastic tips I found would hang up on the lip when feeding depending upon how slow or quickly chambered.

Hope this helps

 

[mehavey]

Before you choose any OAL, pay close attention to the bullet manufacturer's specs in that regard.

Bullet shape/ogive drives compliance with SAAMI chamber profiles -- unless you have done independent length-to-lands measurements yourself on that particular bullet.

Nosler and Hornady both have bullets that can get you in real trouble if you ignore it.

.

 

[44 AMP]

3.340"

This is the listed industry standard MAX Loaded length (loaded length with bullet, measured from the base of the case to the tip of the bullet) aka COAL

CARTRIDGE Over All Length

If your .30-06 is this length OR LESS, it should fit, feed and function through all standard guns. Even at 3.340" normal bullets should not contact the lands.

Everybody's bullets of the same weight are still slightly different in length. Simply look at any 150gr spitzer vs a 150gr RN or Flat point.

Suppose you seat each of those bullets to the same depth in the case. Let's say we seat the base of the bullet even with the bottom of the case neck. The amount of the bullet sticking out of the case will be different lengths with different brands or styles of bullets.

SO, the COAL of each will be different. AND all will be below the max COAL of 3.340"

The length given by maker A for their bullet, different from the length given by maker B for their bullet is normal. ALL are below listed max length, and none of them are the length you HAVE to use. As long as you are below 3.340" you should be fine.

They are just the length the loaders used, when they did their testing. A good place to start YOUR testing with their bullet, but not an absolute carved in stone requirement.

 

[Bart B.]

In the days when the 30-06 was dominant in high power rifle matches, 150 grain bullets shot most accurate with IMR4895 powders with slightly reduced loads. IMR4350 would produce highest velocities but the 1:10 twist most barrels had was too fast for medium weight bullets with maximum loads.

Frankfort Arsenal knew this and developed the 7.62 NATO round shooting bullets about 150 grains 100 fps slower from 1:12 twist 22 inch barrels.

 

[T. O'Heir]

"...doesn't give data for Nosler 150 grain..." 150 grains is 150 grains. You do not require bullet manufacturer specific data.
3.340" works every time. That's SAAMI Max OAL. It was also the length of .30 M1 and .30 M2 ammo. The former used a 174.5 grain bullet. The latter a 152(the 2 grains won't matter). Same OAL.
"...three 30-06 rifles..." You have to work up a load for each rifle. You can forget the off the land stuff altogether. It's 100% optional and 100% trial and error but done, if you feel like it, after you have a load.
"...that's Spitzer, right?..." Yep, but it doesn't matter what shape the bullet is. Reloading is done according to the bullet weight.
"...Starting load 55 grains IMR4350..." It's 54.0 according to Hodgdon. Not enough difference to matter though. All manuals are slightly different.

 

[jmr40]

Please ignore O'Heir. He is clueless.

"...doesn't give data for Nosler 150 grain..." 150 grains is 150 grains. You do not require bullet manufacturer specific data.

Not only false, but possibly dangerous info. Back 50 years ago when all manufacturers bullets were pretty close this may have been true. And as long as you're using very similar bullets it may still be close. But if you're comparing very different bullet shapes and construction, even in the same weight the data is different.

The Noser, and Hornady bullets are close enough to us the same starting data on. But as you approach a max load the 2 could be enough different that a max listed load with one might be safe, and not with the other.

The OAL is dependent on the individual rifle and bullet. Even in the same weight some bullets have very different shapes. A very long 150 gr, high BC bullet will have a much longer OAL than a 150 gr RN bullet.

Here is what I do to determine OAL. #1 I load the cartridge as long as possible that will still fit in the magazines of all the rifles I own in that cartridge. If it fits the magazines and will chamber without jamming the bullet into the lands that is the starting point. If they touch the lands of even one of my rifles I seat them shorter until they do not. I'll load up a batch at that length and head to the range. I could care less what the OAL measures. If they fit, they fit.

If they shoot acceptably, and they usually do, then that is the OAL I stick with. If I'm not happy with the results I can always seat the bullets a bit deeper. Even the ones already loaded and try again. I can't possibly experiment making them longer because they won't fit the magazine.

Most bullets will give the best accuracy if they are seated as close as possible to the lands without hitting them. Doing it this way ensures that. But since every bullet shape is different, and every rifle chamber is somewhat different the exact OAL will vary.

When you see an OAL listed in a load manual that is the number they came up with to get best results with the bullet they used in the rifle they used. It is a starting point, not a goal that you should try to duplicate exactly.

 

[Sequins]

The bullet construction and materials can substantially change the characteristics of the cartridge. Loading a copper projectile with standard data might be catastrophic. Just FYI please look for data suitable to your specific bullet they are NOT the same

 

[Bart B.]

All 150's aren't the same diameter nor have the same jacket metal properties.

 

[Unclenick]

FoghornLeghorn,

The first clue you get that the 30-06 measurements may not be entirely modern is the year included in the name; 1906. That's before SAAMI. It was at a time when headspace and corresponding cartridge case dimensions were determined differently. As a result, there has been some catching up and changing.

The 10" barrel twist originated with the 30-40 Krag Jorgenson rifle which fired a 220-grain round-nose bullet at 2000 fps. When that same bullet was carried over to the 30-03, the rifling came with it. When the 30-03 was dropped for the 30-06 with a lighter bullet and cooler burning powder, the rifling just was not changed, even though it would have been appropriate to go to about a 12" or 13" twist with the 152-grain (-3.0-grain tolerance, making it 150.5 grains on average) spitzer that was later adopted.

The military 150.5-grain bullet has a 7 caliber (caliber being the bore diameter, or 0.300") or 2.10" radius ogive with a tolerance of -0.050", so the shortest ogive radius is 2.05". It has a narrow meplat of about 0.040" on the samples I've measured, giving the shortest ogive a length of 0.729", which is the worst case for our purposes here. Loaded to a maximum length of 3.340" (most samples I have run -0.010" to -0.020" shorter), the straight bearing surface of the military bullet sticks out 0.117 inches from a maximum length case and 0.137" from a SAAMI minimum case (the military minimum is 0.005" longer). For a case trimmed to the standard trim-to length of 2.484", the bearing surface will stick out 0.127" from the case mouth.

As long as you don't exceed that, you shouldn't have a problem with jamming the lands, which will raise peak pressure about 20%.

 

[RC20]

Simply put, Nossler data will be safe in any 30-06.

No one else's bullet mfg data will be that good as their data is for their bullets as each mfg bullet has a different profile as the extreme (valid ) example Unclenick post shows.

Unless you want to really fine tune it and find the lands and move back (.020) then go with Nossler data.

What Lyman uses I do not know but expect its a safe average. For a generic 150 grn soft point they use 3.200 which should be safe.

There are several ways and tools to find that real land contact point if you wan to fine tune it and if closer is more accurate.