Seating Into the Lands or out?

[Hickok]

I have tried all the "benchrest-accuracy" techniques over the years with jacketed and cast. Having rifles with magazines or actions that limit length, or using cartridges which require cannelures/crimping, I now don't fret trying to "touch the lands" or chase seating .010", .020", .030" from engraving the bullet.

I really believe seating a bullet with as little of "runout" as possible gives best accuracy vs seating depth. Keeping bullet runout to .003" or less seems to provide best accuracy. If the bullet starts "straight" at the moment of ignition, it usually enters the throat/lands straight and is accurate when leaving the barrel. A bullet that has .005"-.010" runout starts out "crooked", stays crooked when shot, and the bullet wobbles around its center of gravity and never "trues itself out."

Just my experience. I used to get all worked up when a rifle had a long throat/leade, and I couldn't seat a bullet close to or touching the lands due action length, mag length, etc. It really caused me to not like the rifle!

I have now gotten away from such anxieties, and simply try create loaded cartridges with as little as bullet runout as possible, checking them with an RCBS micrometer sear-up.

I realize in a purpose-made target/bench rifle these things can matter, but for me and my hunting and shooting rifles, with factory throats/leades, and the variables in chambering, I have stopped "chasing the lands" and simply strive for low bullet runout cartridges.

(Yes I have had bullets stay in the throat when the round is extracted and spill powder in the action....what a mess, and also out of a number of rounds loaded to just touch the lands, unexpectedly one will fail to chamber because the ogive is slightly different.)

Many have great success when loading near, or touching the lands, this I know.

[MostlyLeverGuns]

My rifles, lever and bolt guns, a couple AR's and a Mini-14 are repeaters. I load cartridges that will function through the magazines, with a requirement that an unfired catridge will eject without a problem. I do have a Savage 99 in .300 Savage that would feed, chamber, then NOT eject some cartridges. In the 1970's it was not sacrilege, so I filed a small notch in the receiver to allow the cartridges to eject cleanly.
Have run into some bullets that would run into the rifling when chambered, I avoid those bullets for my shooting. I expect 1.5" or smaller groups at 100 yards with my Marlin's and Savage 99's and do much better with my Henry .223 and Savage 99 .243. Loading STRAIGHT cartridges is the most important criterion in accuracy. Jamming a bullet into the throat MAY help get the bullet started straight, but bullet fit in the throat is more important.

[JSnover]

It is embarrassing at best to extract a live round and the bullet stays in the chamber; while the powder settles in the crooks and crannies of your rifles action.
Been there, done that, got the T-shirt!
So I seat bullets to be shy of the “sticking length.”


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That's exactly why I stopped doing it. One rifle would pull the boolit, the other didn't have enough leverage to remove a stuck cartridge without a real risk of breaking the extractor.
Another factor I've run into is an extremely long throat; so long that all but the heaviest boolits won't hit the rifling until after they've cleared the case mouth.

[Bowdrie]

We know that a well-tuned action on a revolver can be very accurate, even though the bullet has long since left the case before it hits the rifling.
Where you can get pressure spikes in rifles is when a hard-jacketed bullet with a lot of neck tension is touching the lands. Then when the powder charge goes off it has to overcome tension and bullet inertia while trying to engrave at the same time.
This is why the mil-spec 5.56 chamber has more free-bore than a civilian .223, (even well before heavier bullets started being used in that cartridge,) it keeps the pressure jump lower.
Hot weather with hot ammo and high pressures with the bullet on the lands is not a good mix.
Heavy bullets also don't "get moving" as fast, more inertia to overcome, I found that my .375 H&H with a 300gr Barnes, (no crimp. lots of neck tension,) shot better when it was seated well clear of the lands.
Of course, there is a big difference between hunting and the smallest obtainable group.
When a hunter is facing a grizzly, (or a soldier facing an enemy,) the last thing they want is a bullet stuck in the lands.

[charlie b]

Yep. Almost all of my shooting is from a bench and I don't hunt. So, all of my cast loads are jammed (including my Garand, which really liked 210gn bore riders). Runout is also important and I used Redding competition seating die modified for my cast loads. Those with too much runout were rejected. And, yes, I do want absolutely the best accuracy I can get. I did stop short of having a custom barrel with a specific neck dia.

If I hunted or for 'serious' use I'd not have a cartridge loaded that jammed into the rifling. I'd take any hit on accuracy over the ability to clear the gun quickly.