30-06 How Many Thou of Lands? Results Posted

It never happened to me either, until it happened to me. Then the situation goes on vacuum. There isn't lot of rhyme or reason to it either, with the only pattern being the odds of sticking a bullet are inversely proportional to the proximity of a cleaning rod.
 
I determine my max COAL by forming a loose fitting case where the bullet can move in and out of the neck with a little pressure. I then feed 5 or more bullets of the same box into the chamber and draw them out carefully, measure them and then average. I always assume as Dogleg has pointed out that I'm jambing them slightly into the lands. Therefore when I seat my bullets I usually seat them .005 to .01 and no closer. This is where I've had my best results. I am however a beginer myself and have loaded about 600 rounds in total.

The one exception I have found is Barnes bullets seem to like being seated a bit farther back like .05 off. In fact I thing Barnes recomends it. I wish I could remember where I read that.

Edit:Here it is. Right off their website in the FAQ section.

Do I seat TSX bullets .030 inch to .070 inch from the lands, starting at .050 inch off the lands, as recommended with other X-style bullets?
Yes. All-copper TSX Bullets typically give better accuracy when seated off the lands and grooves (the rifling in the barrel).

George
 
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g-manz35 said:
I determine my max COAL by forming a loose fitting case where the bullet can move in and out of the neck with a little pressure. I then feed 5 or more bullets of the same box into the chamber and draw them out carefully, measure them and then average. I always assume as Dogleg has pointed out that I'm jambing them slightly into the lands. Therefore when I seat my bullets I usually seat them .005 to .01 and no closer. This is where I've had my best results. I am however a beginer myself and have loaded about 600 rounds in total.

The one exception I have found is Barnes bullets seem to like being seated a bit farther back like .02 off. In fact I thing Barnes recomends it. I wish I could remember where I read that.

George
Click to expand...

Barnes suggests that you start at .050" from the lands. My rifles prefer .050" to .070" with monometal bullets.
 
"Jam" aint just for toast. ;)


6mmBR Loading for Newbies

• C.O.A.L. — "Bullet seating depth is very important. You should get the Hornady (Stoney Point) O.A.L. Gauge (shown below). This will let you discern the OAL at which the bullets just contact the rifling. The trick is tapping gently on the stick. (Get a wood dowel as the bullet can get stuck if you tap a little too aggressively.) With some practice, measuring is quick and you can get repeatable measurements of your distance to lands within .001-.002.

A good starting point for the Berger and Lapua 105s is about .010-.015 IN the lands and then work back. Each barrel is different, but about .010″ in the lands works for many folks. One guy I know started at .012″ in the lands with Berger 105s, adjusted his load up from 30.0 to 30.4 Varget, and within an hour he was done with load dev — the gun was shooting in the low 2s. He went out and won his first match with that load the next day! With the Sierra 107s you might want to start .020″ out of the lands."

Accurate Reloading Tips for the 6mmBR Cartridge
http://www.accurateshooter.com/cartridge-guides/6mmbr-loading-for-newbies/

Multi-Purpose .308 Win Eliseo Tubegun

In this rifle, the Berger 155.5 Fullbore bullet likes to be seated .010″ off what I’m calling “Max Jam”, using a Hornady OAL length gauge pressing the bullet softly into the lands, so the bullet just barely sticks there when the tool is removed. [Editor's Note: At his optimal seating depth, Mark's bullets are still in the lands, just .010" shy of the max length he can load them without set-back.]

http://www.accurateshooter.com/guns-of-week/gunweek0101/

Bugholes from Bipod
Part II — RELOADING
Elements of Accuracy — Making Perfect Ammo
"Now it’s time to seat the bullets. I use Redding Competition Micrometer bullet seaters. I set seating depth so that the bullet is jammed .005″ into the lands on my .308 and .010″ out of the lands on my 6.5-284. You have to experiment with what works in your rifle. Different bullets may also have different seating preferences, even in the same gun. When you are working up loads, always start at least .020″ out. Jamming bullets into the lands wiil increase pressures significantly when you’re running near max."

http://www.accurateshooter.com/shooting-skills/bugholes-from-bipod/
 
A bullet held on the lands with a pencil will suffice for first measurement then rod to bolt face for 2nd.

After initial check, seat bullet longer than measured into an empty case, Polish bullet with steel wool and chamber round moving seater in after each check until you can just barely make out the marks made by the lands on the bullet.

Don't know why you followed bullet with an empty case as it could push the bullet into the lands skewing your measurement results.
 
I read on one of my Internet research journeys, could have been another nutter, whereby you drop a bullet in followed by a sized case and position the bolt to hold in place, then measure. This made "common" sense to me. I used a dowel with two thick tight fitting washers, the initial full length to cocked bolt secured with masking tape around the dowel.

When posted that this likely jammed the bullet and backing up .030 was likely going to be the sweet spot. Tomorrow at the range will determine what results I get, which I will post.
 
I've been trying to develop a hunting load for my 30-06 and must express some frustration in getting clover leaf accuracy. I've developed some very accurate loads for my 22-250, .243 and .270 but wasn't getting satisfactory results with the 06. Now that I've determined some OAL's and tomorrows range test will hopefully verify I know that I've had success in determining bullet length. Based on the measurements, it appears all of my previous rounds were likely to long by alot.
 
So a nice day to do some testing. Here are the results:


(6) different bullet lengths, 100 yards. Left to right and then next row down, the bullets were seated at 0.005, 0.010, 0.015, 0.020, 0.025 and 0.030 off the "jammed" measurements that I took previously, 10 measure average. I only had 23 bullets left to load, so the first go was only 3 shots and all of the rest were 4.




My Weatherby appears to like these particular bullets setback 0.025 off the jammed lands as per my previous posts. This is the load I can now work on with this OAL trying some powder combo's up and down from 56.5 grains of H4350. I am happy with 3/4" of an inch on a 4 shot group, 2 shots into one hole, pretty good results "for me" in this first go at it. I can continue to see if the groups tighten up from here, but for a hunting load, this is a "kill" shot.



Now to track down some of the same bullets. And I will take new measurements based on different bullet batchs have slight dimensional changes.

Comments, feedback appreciated. Thanks for all the input guys, this makes the reloading picture, the OAL portion of it a bit clearer.

Have a good one.
 
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so your best group was 25 thou off the lands with your jammed bullet measurement. interesting, 3.293 is 47 thou shorter than the published COAL of 3.34 for the 06. I never thought of coming up with a value that was shorter. Of course a different shaped bullet may have to be closer in terms of OAL.
 
Yeah, I hummed and hawed once I figured the amounts out, but thought that unless I try it, I won't know what this rifle likes with these bullets. I've tried a number of bullets and powders and formula at book length and wasn't happy with the results. So today, I went out and purchased two steel rods at Depot for $12, Princess Auto was closed but I will stop by later in the week and get some drill stop collars, as suggested by Dogleg, and then I can get some pretty exact measurements for all of my rifles.

Don't know what the stop collars will cost, not much I'm sure, and I've got a "homemade" Stoney Point tool at a fraction of the cost. I love it when a plan comes together.
 
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Congratulations are always in order when someone is able to answer their own question with help from some friends.

My method is to insert three bullets (measured with a comparator) in a lightly sized neck, seated to the lands, and then measured again with the comparator.
Back the seating die off 0.010" as determined by the shortest of the three. This measurement can vary, and varies similarly to measuring just the bullets.
There has never been enough time in a day to measure a whole box of bullets but there was some reason Barnes recommended 0.050 with their older bullets.
The newer Barnes TSX & TTSX are much better in the uniformity department.
A recent reloading session would put the overall (35 rounds) as being 0.013 and 0.017 shorter than the shortest of the three. It is an inaccurate science . . .
 
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