how do you figure seating depth of your bullet

ddhotbot

how do you guys figure the seating depth of your bullets?i want too load some 223 for a single shot and some 308 for my mossberg 800 bolt.i have read that you get better accuracy when the bullet is only 10-20 thousands from the rifling.how can you tell when your bullet is touching the rifling?thanks don

mazo kid

Place the bullet you will be using in the chamber end of the barrel until it touches the rifling. Take a dowel and insert it in the muzzle end until it touches the bullet tip and mark the dowel. Now take the bullet out, close the action and push the dowel in until it contacts the bolt face. Mark it. Now remove the dowel and measure the distance between the marks; that is your max OAL. Subtract your desired spacing from the rifling. Set the dimensions up on your reloading press and test. Emery

temblor

In addition to the simple method mentioned by mazo kid, read my post in the "300 RUM Pet Loads" thread in this forum.
It pretty well explains some entry level tools you can aquire/use.
If you use the dowel method you'll need to be able to get a bullet in a case neck that fits tight enough to stay put. Don't push it hard enough to push the bullet down farther in the neck or you'll lose the proper measurement.
If you want to do it without tools another inexpensive way, you might try this. Take a brass case that has been sized/resized and split the neck in three places (with a thin blade of something you have like a dremel or small set of snips, etc.) to make it look like a collet. Seat a bullet in the empty case out long. Mark the side of the bullet with a black marker and insert the dummy cartridge in the gun and close the bolt on it gently. This will allow the bullet to be seated in the case deeper by the lands/rifling. Then remove it slowly and look at the black marked part to see if it moved when you removed it. If it did, reseat it to the depth of the marks and measure it. This should give you the OAL to the rifling. Then seat your bullets a little deeper to the clearance off of the rifling that you want.
I like this way better than the dowel method because you don't run the risk of seating the bullet deeper with the dowel.
Or -- you can buy some tools [:D].
Good Luck..............[^]

JustC

spend around $25 in the sinclair catalog and buy their seating depth tool. It uses a fired case from your chamber as well as a bullet dropped into the rifling of your barrel. This is the surest way of getting a bolt face-to-rifling measurement.

sandwarrior

ddhotbot,

A basic method is the stoney point tool. Matched with a drilled a tapped case that screws onto it you get a very close approximation of where you need to seat the bullet.

The tool you get from Sinclair that JustC mentions is a better method...for a few bucks more. Which is not much in the big scheme of things.

For fun I took a fired case and drilled it and tapped it to 36tpi and made my own case measurement tool to work with the Stoney point. It was a PITA(just finding the tap) but it works well for that caliber.

-good luck

redboneusa

I also use the stoney point gage. I remember the days of "smoking" the bullet with a candle, what a pain. I am lucky enough to live near a great source of drills, taps, die and such. Beaver Tool company has all of this stuff. You can check them out at www.beaverdrill.com. I bought the tap required to make the modified cases for the stoney point for three or four dollars.
Good Luck

deadeye46

dd,this probably isn't the answer you're looking for but I usually have in my die boxes a factory round for each caliber to set each seating die with.That way I can fire them in any of my rifles or my friends rifles of the same caliber.just a thought

Rob Greene

That's what I do. I just compare it to a factory made one. I figure that they got it right at the factory. (Plus I check my reloading book to make sure everything matches up to what it should otherwise!)

temblor

deadeye & Rob Greene :
That's fine if your just hunting, etc., but if your trying to set a bullet a close distance to the rifling it doesn't help you much.
Most factory ammo is seated short to work in a wide range of guns, just as was mentioned.
Doesn't work well for serious accuracy work in most cases...........

n/a

Optimum seating depth is going to vary from gun to gun, but I've found that most of mine shoot best around .005 off the lands. Stoney Point makes an affordable tool to help with this process...

plains scout

The methods mentioned here are better than the method that i have used in the past so I am switching.

If you are like me (technically inept) I think I would do both the dowl method and the tool made for the job.

I am trying the dowl method next week on a guy. good post. great answers.

temblor

quote:Originally posted by plains scout
The methods mentioned here are better than the method that i have used in the past so I am switching.

If you are like me (technically inept) I think I would do both the dowl method and the tool made for the job.

I am trying the dowl method next week on a guy. good post. great answers.

I made a fairly in depth post on using the Stoney Point tool in another thread titled "300RUM Pet Loads" in this same forum that might be worth reading if your interested........................

jonk

Take a fired case from that chamber. Take a bullet you want to use in that gun. Size the neck perhaps 1/16". Start the bullet into the case with your seating die so it just grabs. Slam the cartridge into the rifle's chamber. The rifling will grab it and force it into the case. Measure the result with your caliper. Insert this back into the seater die and screw the seating plug down to this depth. Turn seating plug a tad more; measure. You want about .005" or so, but whatever you decide on, that gives you a measurement for that particular bullet style. Similar to what REmblor mentioned.