Seating depth, etc

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Camaroguy

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Hey all. I have a few questions I'm hoping the experienced folks can help me with. I've been reloading for my 30-06 for a few years now, but I've just been cranking them out using the settings my old man used for his Remington 742. I'm reloading for my 700 now and have decided to make some rounds suited to it. So I got some Speer 168 gr bullets (they were out of sierras and I'm still messing around figuring things out) and set to figuring out where my lands were. Using my original settings, I had almost a quarter inch jump to the lands. I've got it down to 0.090" and if I go much further the bullets are loose and not aligned properly. Is 0.090 alright or is it still so far off as to make no difference? Still way under mag length so no worries there.

Next question, regarding the ladder test. I loaded up 18 rounds in half grain increments from starting charge to max charge of H4895. Due to shooter error, I'll have to reshoot the test, but the one thing the test showed me was that even at max there were no pressure signs that I could see. Is it safe to increase on the max, seeing as max for one rifle would different in another, or should I leave max as max? I don't really need the added velocity, max charge gave me 2740 fps, I'm just curious.

Thanks in advance for the help and I apologize for the rambling nature of this post, I'm working my fourth shift in two days.
 
Book max's are done by pressure specs IIRC, and can be conservative. You can exceed them in most rifles, just do so carefully. If you do load near, at or above book max, watch the temperature sensitivity.

As for seating, a good rule of thumb is to have at least one caliber of the bearing surface of the bullet in the neck. So for .308, you should have at least .30 of contact between the bullet and the neck. A factory 700 has a very long throat, odds are you won't be able to get anywhere close to the lands without having the bullet literally falling out of the case.

Best bet, just set it to what your manual says.
 
I figured the book would be conservative. Makes sense. I think at .090 off the lands I only have .150 of the bearing surface in the case neck. So basically just run it as is unless I wanted to cut the chamber end of the barrel .200 and rechamber, which on a stock barrel I don't. Thanks for the help.


How would I deal with temp sensitivity near max? Work up the load again at different temps to make sure it's still safe?
 
Camaroguy said:
How would I deal with temp sensitivity near max? Work up the load again at different temps to make sure it's still safe?
Click to expand...

That would be one way. Or just don't load near max. Most rifles have 2 or 3 nodes in the upper ranges of charge weight, just don't use the highest one.
 
Well - Most rifles will preferentially tune to a particular bullet weight. And that load will show promise right out of the gate. On the other hand, you could spend the next month trying to get your 168's to shoot... Try a couple of three shot groups, just to see whether you have a 1 moa situation or a 3 moa situation going. (I've shot for years, and never bothered with a ladder test. I try two or three bullet weights, all flat base, pick the best one, and tune with powder charge. Distance to lands is a minor consideration for a hunting rifle.)
Also, give yourself some margin from book max, consider it your safety factor for reloading errors (it will happen). Rifles generally dont show their best results at max anyway.
 
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Try shooting a heavier bullet weight.
The 30-06 can handle the heavies very
Well!

I regularily shoot 190-200 grain bullets. They are also longer in the shank, and allow you to seat the bullet further out of the case (closer to the rifling) and still have enough in the neck to allow proper alignment.
 
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