New Ruger No. 1 here, 45-70 Govt.

I'm loading spec on case length, 2.100" and seating Speer 350 gr. FP to the cannalure. The cannalure doesn't show in the seated/crimped case.

And so, sliding a round into the chamber, the bullet sets hard against the lands, actually makes indentations in the copper jacket.

Online sources suggest seating 0.015" to 0.030" off the lands. Sniper Country says "just touching" or about 0.001" off the lands.

These bullets aren't "just touching" -- they're butt up tight against the lands, action is tight to close on the round.

Comments? Observations?

Is there really any need to have the crimp in a single shot? Find the overall length where it touches and then back off from there.

If you wish, the bullet can be seated to be in full contact with the lands. It's fully safe! It is possible however for the bullet to be so stuck into the lands that the bullet is pulled upon extraction of a loaded and unfired round and this can leave an obstructed bore for the next round.....not good!!

IMO the issue of "distance to lands" is way over worked.....there may be a benefit occasionally but it's not one of the things I get excited about. There is no single place to seat a bullet for accuracy!

Weatherby rifles were guaranteed for accuracy with a freebore for gosh sakes.

If you do choose to seat into (or at least contacting) the lands be aware of pressure issues when you work up your loads. It is possible your pressure will rise in this configuration.

IMHO, bullets vary enough over the ogive, that it is very unlikely you can seat consistently off the lands with a .001" clearance (as you indicated Sniper Country had suggested). What will most likely happen if you try to seat as close to the lands as that, is that some bullets will touch the lands, and others may not. Personally, I try to stay away from that configuration. I have found even match type (factory) bullets to vary as much as .005" or more when measured over the ogive of the bullet. Therefore, if I try to seat off the lands (which I normally do to avoid issues of sticking bullets when extracting a loaded round), I stay at least .005" away from the point where the bullet would nominally touch the lands. YMMV...

- mike

I would seat the bullet to the depth needed to no more than kiss the lands. You don't really need a crimp on a single shot. As long as the case is not flared out it should hold the bullet just fine.

Seems like a lot of hoodoo about bullet seating depth.
An old timer back when I started loading rocks in a trebuchet, advised me to do the following. Make a dummy case, seat a bullet in it, smoke the bullet with a candle or now a butane lighter. Shove it in the chamber look for marks on the bullet, turn the seating stem down, smoke it again shove it in, check for markings on bullet repeat as necessary.
When you don't get marks on bullet stop!
Lock seating stem.
Proceed to blissfully load.
Jim

Smokin' rocks in a trebuchet -- hmmmmmm. That's gotta be a lot of work. And then what? Look for "sling marks"???

OK, so "crimp" as in bring the belled cass back into the diameter of the chamber. It's not "rolled" to hold the bullet.

"Kiss the lands" -- slight indentations, not enough that the lands will grab the bullet and hold it during extraction.

I suspect the engagement of the ogive into the lands is in the realm of 0.001". That's a "hair". (Actually a "hair" is about 0.002".)

Now that I have the chamber to check, I'll go back and seat the bullets a bit deeper. Gun has been at Ruger getting the lever latch replace. I expect the screw in the latch came loose from all the recoil.

Lands in the barrel make me expect -- along with the overall condition of the gun -- that this rifle hasn't been fired much. Previous owner probably traded it in for a .17 Hornet or something in neighborhood.

More here --

Set the calipers to the OAL and checked, then seated the bullets until the marks disappeared and the rounds locked up easily in the chamber. That set the bullets about 0.020 deeper than previously loaded.

These are the first loads for this rifle. All new specs.

Then I went out and assassinated a couple gallon milk jugs full of water behind the barn. The scope needs some sighting in. That when this weather clears up.

Hasn't been too long since I posted this, but there's a super easy way to check for land contact length. I didn't invent it, I saw it on some board and am passing it along:

Take a bullet of the type you're loading, and a rod. First, push the rod down the muzzle till it touches the face of the closed breech. Mark the rod at the muzzle with tape to show how deeply it went in. Gently push the bullet into the breech till the rifling stops it. If you have another rod to hold it there, so much the better, but if you're careful it'll stay there. Take the rod and slide it gently down the muzzle again till it touches the bullet nose. Mark it again with tape. The distance between the two marks is the cartridge overall length at which the bullet butts up firmly against the rifling. You can go from there figuring out your desired seating depth.