Distance from the lands

[OrangeSpear]

I know there are home remedies for finding this info but id like to own a tool made for this.


I want to find the distance to the lands so that i can seat my bullets accordingly.

After hours of research, i have narrowed it down to 2 products but am confused as to what the difference is.

Hornady® Lock-N-Load™ OAL Gauges formally known as Stoney Gauge.

Easy-to-use, precise overall length (OAL) gauge provides essential load dimensions quickly and reliably. Accurately determines overall cartridge length for proper bullet free run and bullet-seating depth dimensions; firearm throat dimensions; and extent of throat erosion. Simply thread on any Chamber-All Modified Case. Made in USA.
Available:
Straight Gauge – fits any bolt-action or single-shot rifle or pistol (shown).
Curved Gauge – fits any lever-action or semiautomatic rifle.

Requires threaded modified case, sold separately.
This item works on all firearms with straight-line access
to the bore. Simply thread on any Chamber-All Modified Case.

Hornady® Chamber All™ Bullet Comparator

When setting up your bullet seating die, correct bullet seating depth is critical to accuracy. The comparator will eliminate bullet length variations, allowing measurements to be made from a reliable reference point – the bullet ogive. Attaches to your caliper with a thumbscrew. Caliper not included.
Available:
B-2000 Comparator body and six bullet inserts in the following calibers: .224" (5.56mm NATO), .243 (6mm), .257", .277", .284" (7mm), .308" (7.6mm)
B-2000 Comparator body and 14 bullet inserts in the following calibers: .172", .204", .224" (5.56mm NATO), .243" (6mm), .257", .264", .277", .284" (7mm), .308", .338", .358", .375", .416", .458"

My question is which one do i need??
but while typing this up i feel i just realized something, i think I will need both. one tool kind of requires the other tool.

 

[K31]

Yes, for the most accuracy you need both.

Measurements from the tip of the bullet are in consistent even with match bullets. Your seater die contacts the bullet on the ogive, just like the comparator does.

 

[4570inMD]

...I want to find the distance to the lands so that i can seat my bullets accordingly...

Good article here by the USAMU:
http://www.gunsamerica.com/blog/case-overall-length-coal-reloading-tips/

4570inMD

 

[DarrellA]

I eventually gave up trying to find or rig modified 7mm-08 brass in order to use the Hornady guage. I used the method with a cleaning rod and a pair of Possum Hollow cleaning rod stops. Amazingly easy, much less expensive and, as far as I can tell, it works just fine.

 

[IndispensableDestiny]

I eventually gave up trying to find or rig modified 7mm-08 brass in order to use the Hornady guage. I used the method with a cleaning rod and a pair of Possum Hollow cleaning rod stops. Amazingly easy, much less expensive and, as far as I can tell, it works just fine.

The modified brass is easy to make. All you need is a 9/32 bit and 5/16-36 tap. You'll have to order a tap online, it's a non-standard size. You can also send your fired brass to Hornady and they'll make one for you.

Or, you can just order a case and wait for the backorder to fill.

As for the OP, you need the OAL gauge and the appropriate bullet comparator.

 

[Pinecone]

The first one is used to measure the throat depth on your rifle.

The second is used to measure the shoulder length and overall length to ogive (curve of bullet). With two of them, you can measure the bearing surface length of individual bullets.

For the first, you can do without it by taking a case where a bullet fits snugly but not tightly. Seat a bullet just barely started, then slowly chamber the round. Then slowly extract the round. The lands should push the bullet back in the case. The bullet needs to be loose enough to move, but snug enough to not move on its own.

Then measure with the second device and that is your max length to ogive. As has been mentioned, length to meplat (tip of bullet) is not consistent. Length to ogive is what you want to use.

The second one is used to adjust your sizing die to bump the shoulder the minimum amount. 1 - 2 thousandths for bolt rifles, 3 - 5 thousandths for semi auto.

If you only get one, the second is is used all the time. The first one is only used occasionally (to get initial setup, then occasionally to check throat wear).

 

[K31]

You move the bullet back and forth in the modified case, in the firearm chamber using the OAL guage until are satisfied that it is just touching the lands and lock it down with a set screw.The second device, the bullet comparator is first used on calipers to measure the overall length of a modified case and bullet, just touching the lands while still on the OAL gauge. You back off on this measurement a number of thousands of an inch and measure your seated rounds using caliper with the bullet comparator to determine that you have seated to this depth.

 

[OrangeSpear]

http://www.youtube.com/watch?v=kaA3GECbbVA

seems like an option too.