I feel like I'm asking if I should unwrap gum before chewing it.......but here comes my silly question for the day:

Is there an IDEAL bullet seating depth?

I have been loading for the last 45 years and always seated my bullets by pushing them into the case just far enough that the bullet starts to touch the lands.......then seat them a tad more.
Nothing terribly scientific about it. Of course with some guns I had to modify this technique to fit the magazine box or facilitate feeding. But by and large this has been my method and it's worked fine.

Now that I've grown old and "smart" I've started measuring my seating depths and come to realize that I generally seat bullets way long according to factory "overall maximum length."

And when I seat bullets so the overall cartridge length meets factory specs, the thing looks stupid and seated too deeply to me.

Have I been a bad boy all these years or how important is it to pay any attention to these factory guidelines?

Color me dumb.

Sure is...

But it depends totally on the bullet you are using and the firearm you are using.

One size fits all is nice in flip-flops that you are wearing on the beach, but not in boots that you are planning on doing a 100 mile trek in!

Factory specs gotta suit all guns. Your loads only gotta fit your guns. You ain't dumb at all.

Us old farts gotta stick together.

Good point, Leftover. I figured I haven't been going too far afield all these years since I've never blown myself up or damaged a firearm. And bullets generally come out the proper end of the thing.

I guess I was just afraid I was suddenly violating the "Pure Food and Hog Law" or some such.

My kids would never live it down if their Pappy was in the slammer for seating his boolits too long.

Listen to Swede. Varying seating depth is a good way to improve accuracy, and I have always had my best luck anywhere from slightly in the lands to .01" off the lands, no further off. For every .270 I've owned and loaded for, I have been pretty close to right on the lands as well as for one of my 300WM. For my new WM, it likes it .005" off the lands and for my 22-250, it likes the 69 grain SMKs off .01". Buy a stoney point bullet comparator or the one from sinclairs and measure length with this. Vary seating depth .005" at a time and less later to fine tune if desired. Usually, there IS an ideal seating depth, you just have to find it for your rifle and your loads. This seating depth will be consistant with bullets of the same bullet profile for the same rifle unless you are in competition and use VLD bullets which often like to be on or soft seated in the lands. Bullet profile will also change from lot to lot and it is good to buy the bullet comparator so you can adjust the seating plug on your die accordingly.

My 223 simply will not shoot a bullet that is touching the lands. It wants a "Jump" of about .020" to maintain good accuracy. I've loaded some rounds this morning to test in my 6MM BR which have the bullets seated .005" into the lands. We'll see how that works out.

Rick

Pecos, your way has worked fine for me and it still does. I think we sometimes get too done up with our new and improved capacity to measure things.
As far as an Ideal depth is concerned, I can only quote my favorite instruction regarding reloading: "Each rifle is a law unto itself and generalizations should be made with circumspection."

Pecos,
if the mag is not the limiting factor, I measure the chamber to a bullet just touches, and then back off .027 or so... unless it's a DGR, where I have to crimp

all the books say that best accuracy comes from a "slightly" longer oal...

my 257 bob, in this case, is SLIGHTLY more than slightly... like .150 longer...

I wouldnt shoot those in any other gun, but, then again, I wouldnt shoot ANY of my reloads in a gun that I hadnt built the load for

Beeman/Jeffe - thanks for the confirmation guys. Most of my loading career I just loaded stuff that "looked right" and "worked good" and was a happy camper. Now, in my dotage I have gotten anal about everything and bought all these mikes and crap to measure everything and all I do is worry about crap that doesn't amount to a hoot in hell in the real world.

Maybe this is a sign of senility. I think I'm gonna go back to the old ways that were good enough for the forefathers.

I'll try to think up something better than this to worry about at night when I oughta be asleep.

Pecos,

The only thing to add would be if you were planning on hunting dangerous game. If the bullets are not seated deep enough there is a small risk you could end up with a magazine full of loose bullets and powder after the first shot. In this case alone, I think function outweighs ultimate accuracy, and the rule of thumb is to seat about as deep as the bullet is wide.

IMHO.

Patrick

Patrick has a point. I generally look for a caliber seating depth or more. Sometimes will go less for single shots.

Pecos, aside from the other lumps of good commentary you got on this, it might be of interest that Nosler does not generally include OAL in their load recipies, preferring to advise how to adjust that for your own rifle. Depending on a long list of variables you may actually reduce peak pressure in your loads by seating long. Some years back R. Jamison was fiddling with his Oehler and testing loads for increased pressure due to firing them with the bullet engaged in the lands. Curiously enough he found larger increases by changing primers than by engaging the bullet in the lands. The increase that he did get was less than you'd expect from standard deviations in SAAMI spec. ammo.

I've read that smaller calibers prefer more jump than large, as a general rule. You couldn't prove it by me.

I have been loading about as long as you have and just this year 'discovered' how sensitive a rifle can be to oal. I always believed that close to or just touching the lands would produce the best accuracy, but I have found that I can shrink groups 50% from my squirrely .270 by changing o.a.l by as little as .005"! What really surprises me is that I am over .100 off the lands (fairly long throat). My very repeatable '06 also seems to respond to very slight changes in oal. Now I have to do a bunch more bench work with the rest of the rifles to find what they like, and does the amount of jump change for each style of bullet. What I wonder is it really bullet jump or does it have to do with case capacity, powder space or all of the above?
C.G.B.

CGB,

You find the answer to that one and tell us. I doubt it is just as simple as a bullet for a certain cartride "liking" a certain amount of jump. Has to be more to it than that. I'm sure there are people out there that are a lot more anal about it than I am and have a lot more money and have come to a conclusion.

Good, sound comments from one and all here! Beeman, I think you've about summed up all the comments here that every rifle is a law unto itself.......or as I've always thought of it, "Every rifle has it's own personality."

I have everyone's loading book and always liked to consult and read all of them but in my dim mind I hadn't noticed that Nosler doesn't include a max cartridge length.

It's comforting to know all of you guys really are your own judge and jury about this issue. I was a whole lot happier when I did it that way myself.

Time for this old dog to back up and do it like he's been doing it. <Sheepish grin>

You'all realize, of course, that with some rifles it's impossible to seat to the lands because those rifles are deliberately built with freebore -- Weatherby mags being a notable example.