.30-06 load development, bullet seating depth

[Morrey]

New gun, Weatherby Vanguard Wilderness .30-06. During my first phase of load development, I'll use Hornady gauges to allow me to read to the bullet's ogive and measure COAL when it touches the lands. With this particular caliber, should I then set my bullet seating depth Thirty one thousandths back off the lands for starters? Obviously I'll test lots more, but is this a common starting depth?

My first test load sequence will be with Nosler Accubond 165 or Hornady Interbond 165. I realize to take a dummy loaded round to the depth I will use and make sure it will chamber as well as fit in the magazine w/o the tip hitting.

Thanks!

 

[243winxb]

http://www.thehighroad.org/showpost.php?p=9228970&postcount=19 Seating near the lands is overrated in a factory chamber.

 

[W.E.G.]

You might have more fun playing with seating depths if you were using a benchrest-type target rifle.

Its not likely that you will fire enough rounds with a hunting rifle to obtain a statistically-valid sample to support any conclusion that one load is significantly superior to another.

You gotta remember, that hunting rifle barrel is going to get way-hot after firing only a few number of rounds. Hot barrels on any rifle (hunting rifles worse than heavy rifles) will start to fling shots very wide.

Unless you can come up with a cooling system for the barrel, you will need to spend many, many hours.

For a hunting rifle, you will be best served spending your time scouting your hunting area.

 

[jmr40]

Here is what I do. I load 1 round as long as possible that will still fit and feed from the magazine. If I own multiple rifles in the same cartridge I load to fit the one with the shortest mag box. If it feeds without hitting the lands in all of my rifles in that chambering I load more and head to the range. If they touch the lands I keep seating it deeper until it no longer touches in any rifle. Most of the time I'm good to go at that point.

I have no clue how far off the lands I am. But I know I can't seat it any farther out and if I'm not getting good accuracy the only way I can go is to seat them deeper. But I've only ran across 1 bullet that worked better seated deeper. That is the Barnes TTSX's. They are one of the rare bullets that shoots better if seated deeper than normal.

 

[Bart B.]

In the heyday 0f the 30-06 being used in bullseye matches, rounds with an OAL 1/16th inch shorter than magazine length were excellent for accuracy and reliable functioning. It worked best with new cases or full length sized ones.

As the bullet's ogive contact point to the rifling (leade or throat), rifling eroded away and moved forward about .001" for every 30 rounds fired. Bullets had to jump about 1/10th inch further to the rifling after 3000 rounds of barrel life. By then, accuracy had lessened to no longer be com0etitive. Seating bullets further out in the case didn't help very much. To stay competitive, a new barrel was needed.

Nothing's changed today. I'd just seat bullets as mentioned above then shoot the darned things. You don't need to "chase the lands" seating bullets shallower every so often. Change the charge weights in 1 grain increments then shoot 10 to 15 shot groups to see what produces best accuracy.

The only barrels that no longer shoot to point of aim as they get hot are ones fit to receivers whose face ain't squared up with the tenon thread axis. Fix that and you can shoot dozens of shots 15 seconds apart and they'll all shoot to point of aim. If the barrel's stress relieved properly; if not it'll string shots as it gets hot.

 

[mdi]

For all my rifle loads I start with the bullet manufacturer's recommendations for their specific bullet. I'll concentrate on finding a good powder charge, then try different primers, mebbe play with crimp, or lack of, then I'll try seating depth/distance from lands. Changing one thing at a time, and recording results. For my guns, I've found seating depth variations from manufacturer's recommendations to be the least important/effective accuracy item...

 

[LoonWulf]

this is gunna sound dumb....i seat bullets about as far out as i can...cause i like the way it looks....

really

I honestly havent seen much difference in my rifles, all of which are hunting weight, with seating depth untill it gets quite short. If a bullet/powder combo dosent shoot good at book spec +/- it usually wont no mater where you go. Again tho, theres always variation, might find a sweet spot in coal that just WORKS.

Only experience i have to the opposite (and again this is just my experience), is my buddies 7mm rifle and dies. Hes got the same dies i do (lees), but for some reason his dies produce more run out than mine do, visibly more. When loaded at factory spec he had poor accuracy, when seated deep they seemed to straiten out on the way forward? his accuracy still wasnt good, but it was better then when he loaded long.

 

[Gtscotty]

I usually start about 30 thousandths off to settle in on a favored charge weight. Once I get a promising charge weight, I'll load several batches shorter and maybe one longer in 10 thousandths increments (for hunting rifles). If I have an OAL range that looks better than the others I'll load up a few more batches and make sure it holds up. That basic procedure has worked well enough for the many rifles I've developed loads for (I have a bad habit of getting bored of rifles once I've got an optimal load, and moving on)

 

[philip brousseau]

Morrey i have seen this work many many times. i use sierra bullets .010 off the lands. fed 210 primers and h4350 powder. start with a safe charge of powder and shoot paying attention to pressure. as you increase the powder charge the groups should tighten. i've had 3006 rifles that would not shoot 165s real well but the same gun would shoot 150s extremely well. just have to see what it wants. let us know how it goes.

 

[Morrey]

Maybe I'll get lucky and nail a good load right off the bat and be done chasing a decent load. Weatherby guarantees a .99 MOA group with the right ammo. Humm....."right ammo" is a mighty subjective term. I have had good results with IMR 4350 in this caliber and I have several lbs on hand. Like I say, maybe I'll get lucky.

 

[30Cal]

I default to 0.020" if there's room in the magazine.

 

[Decoy80]

I would invest in an RCBS 30/06 chamber mic. Also I would load seperately for the match rifle. Its not all that expensive to purchase and rather cheap when seeking great accuracy. Good luck and enjoy yourself.

 

[Hardtarget]

And from all the variations of primers, powders, bullets and tweaking seat depth and crimp or not....we'll darn near have the barrel shot out before we find that "golden load". bummer. :banghead:

Now we need a new barrel so we can start over!

reloading is fun!

Mark

 

[Gtscotty]

I would be very surprised if you couldn't find a good deer load using 165gr Sierra Gamekings and a 4350. If you want to minimize your load development, that's where I'd start.

 

[Morrey]

I would be very surprised if you couldn't find a good deer load using 165gr Sierra Gamekings and a 4350. If you want to minimize your load development, that's where I'd start.

All rifles are different, but I happen to have a box or two of Sierra GK 165's...also a box or three of Sierra GK 150. I found a sweet load for a Cooper .30-06 with 56 gr of 4350 pushing a 165 SPBT.

I may try 55gr, 56 gr and 57 gr and see what my MOA looks like. I think this may be close to the sweet spot.

 

[Morrey]

I usually start about 30 thousandths off to settle in on a favored charge weight. Once I get a promising charge weight, I'll load several batches shorter and maybe one longer in 10 thousandths increments (for hunting rifles). If I have an OAL range that looks better than the others I'll load up a few more batches and make sure it holds up. That basic procedure has worked well enough for the many rifles I've developed loads for (I have a bad habit of getting bored of rifles once I've got an optimal load, and moving on)

Thanks! I was looking at my notes to find my "starting" point for bullet seating. I thought it was 30 thousandths off the lands and you confirmed this. I hope to find a load that works and move on w/o lots of fussing over a load. This is a hunting rifle and actually one I will use as a back up, but I'll let my wife use it when she goes with me once in a blue moon. Who knows...she shot a trophy wild boar last time we went last fall. Plus I have a drive for accuracy and not much of one who thinks that getting close is good enough. If I have a gun who's maker guarantees .99MOA, I think we should find out and hold them to that claim. On the other hand, I don't plan to spend countless hours and big reloading component dollars chasing a match grade round for a mid-grade hunting rifle.

 

[Bart B.]

If you've a drive for accuracy and are not much of one who thinks that getting close is good enough with 165 grain bullets, don't use IMR4350 powder. IMR4064 powder has produced best accuracy with that weight for decades.

Does it matter the 165's will leave 50 to 75 fps slower than IMR4350 will shoot them with equal peak pressure?

 

[Gtscotty]

If you've a drive for accuracy and are not much of one who thinks that getting close is good enough with 165 grain bullets, don't use IMR4350 powder. IMR4064 powder has produced best accuracy with that weight for decades.

Does it matter the 165's will leave 50 to 75 fps slower than IMR4350 will shoot them with equal peak pressure?

What do you think the accuracy difference will be between optimal loads of 165 gr hunting bullets in a hunting rifle using IMR 4350 and IMR 4064? You must have some idea given your assertion that 4350 is close, but not good enough for the OP's purpose. Do you believe that this difference in accuracy will even be observable in a lightweight hunting rifle, much less justify the OP going out to buy more powder even though he has several pounds of a perfectly suitable powder already on the shelf?

 

[Morrey]

What do you think the accuracy difference will be between optimal loads of 165 gr hunting bullets in a hunting rifle using IMR 4350 and IMR 4064? You must have some idea given your assertion that 4350 is close, but not good enough for the OP's purpose. Do you believe that this difference in accuracy will even be observable in a lightweight hunting rifle, much less justify the OP going out to buy more powder even though he has several pounds of a perfectly suitable powder already on the shelf?

I had done some testing for my Cooper .30-06 with the 165's and found the 4350 grouped well ahead of the 4064. Luckily I do have close to a lb of 4064 on my shelf so it would be an easy test. As stated, the Cooper loves 4350 and not 4064 so much. BUT, this all can change with this Weatherby.

BartB question: when you test loads and know heat in a hunting rifle barrel may cause accuracy issues, at what pace do you fire your test groups? Very quickly?

 

[Bart B.]

When I test loads and know heat in a hunting rifle barrel may cause accuracy issues, at what pace do I fire the test groups?

One shot every 15 to 20 seconds until shots start grouping in the same place. That's when the barrel's reached its stabilized heat an bent as much as possible moving the bore axis someplace where it'll stay for a given metal temperature. Then I shoot once every 15 to 20 seconds for a 15 to 20 shot group that tells me what the accuracy is.

That hot barrel accuracy has proved to be the same with a cold barrel shot once every 5 to 10 minutes. Only the group center from point of aim changes.

Barrel size and profile for a given cartridge doesn't matter any significant amount; they all will drive tacks, so to say, if the barrel and the rest of the rifle are of good quality and build.

That said, I've never worked up any loads for any of my cartridges; one exception. Just used with others use getting best accuracy. That above stuff was done with 3 hunting rifles using loads got from others just to see if they shot as good as the other folks got. Because they did, decided that working up loads was a waste of time.

That exception was for a new bullet for which no load data was ever worked up; I and a few others were the first to get them.

On the 2 or 3 commercial factory sporting/hunting rifles I used, both had their receivers' face squared up so the barrel would not walk shots as it got hot. After facing off the receiver a few thousandths, a shim of the same thickness was put between the barrel and receiver so it would clock in to correct headspace. That was a long time ago; details are no longer important to remember.

 

[Morrey]

When I test loads and know heat in a hunting rifle barrel may cause accuracy issues, at what pace do I fire the test groups?

One shot every 15 to 20 seconds until shots start grouping in the same place. That's when the barrel's reached its stabilized heat an bent as much as possible moving the bore axis someplace where it'll stay for a given metal temperature. Then I shoot once every 15 to 20 seconds for a 15 to 20 shot group that tells me what the accuracy is.

That hot barrel accuracy has proved to be the same with a cold barrel shot once every 5 to 10 minutes. Only the group center from point of aim changes.

Barrel size and profile for a given cartridge doesn't matter any significant amount; they all will drive tacks, so to say, if the barrel and the rest of the rifle are of good quality and build.

That said, I've never worked up any loads for any of my cartridges; one exception. Just used with others use getting best accuracy. That above stuff was done with 3 hunting rifles using loads got from others just to see if they shot as good as the other folks got. Because they did, decided that working up loads was a waste of time.

That exception was for a new bullet for which no load data was ever worked up; I and a few others were the first to get them.

On the 2 or 3 commercial factory sporting/hunting rifles I used, both had their receivers' face squared up so the barrel would not walk shots as it got hot. After facing off the receiver a few thousandths, a shim of the same thickness was put between the barrel and receiver so it would clock in to correct headspace. That was a long time ago; details are no longer important to remember.

Excellent. Thank you!

 

[rg1]

Hornady recommended seating depths in two of my factory Remington bolt actions, a 30-06 and 25-06 had about .050" jump to the lands. This could be just coincidence but factory ammo is designed to fit magazines and to chamber in most all rifles without jamming into the lands. My 30-06 I seat to Hornady's or other bullet company recommended overall lengths. My 25-06 looking for long range varmint accuracy I experimented with seating depths starting at .050" then 040" and .030" and .020". I also tried some .010" off but I did not want and did not try closer or jammed into the lands. Just so happened with my 25-06 that it shot slightly tighter groups at .030" than other lengths. All rifles are different animals and what works in mine may not do the same in yours. I would not load any factory rifle for hunting with any bullets closer than .010" and better at .020" minimal length from the lands.

 

[Bart B.]

With full length sized cases with their necks straight and best centered on their shoulders and in line with the body axis, I've seen no significant difference in accuracy with bullets touching the lands to over a tenth of an inch jump.

That's across several rifles and barrels with different chamber, bore and groove dimensions, so I don't think all rifles are that much different. Evidenced by the same lot of commercial match ammo shooting equally accurate in rifles with jump-to-rifling spread's near 1/15th inch.

However, if there's a lot of bullet runout 'cause the case necks (and therefore bullets) are crooked, seating bullets shallow so they push back a few thousandths as they go into the rifling does improve accuracy by 1/4 to 1/3 MOA.

 

[sage5907]

When shooting 30-06 rounds with 150 grain boattail bullets you have to be concerned about the amount of bullet that's in the case neck. If you seat them where they are touching or into the lands they may pull out easy if you extract a loaded cartridge. I have found that on 150 grain boattail bullets it works for me to seat the bullet so the base of the bullet is even with the back of the case neck. Accuracy is excellent in several rifles. My favorite loads are 51 grains of IMR 4064 with magnum primers and 57 grains of Reloader 17. Reloader 17 is the most accurate powder I have found for a 30-06 with 150 grain bullets. The IMR 4064 load has the least recoil and is a pleasure to shoot.

 

[Bart B.]

While seating bullets so some part of their back end is at the case neck-shoulder junction is often claimed best for accuracy, it's not what's proved best for accuracy amongst people getting best accuracy.