Noob advice seating depth

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m-14custom

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Hey guys and girls. I was trying to figure out how to seat my bullets so im .10 off the lands. How do you figure it out? I was told to build a dummy round. Smoke the bullet and then load it into the rifle to see if it touches the lands then back it off .10. Is this what everyone else does?
 
I use a magic marker, and do just as you described. No need to get technical.

A bullet comparator will also be a useful tool in your gear to help ya out with seating depth, cheap peace of mind.
 
Build your dummy load using a partially sized case fired in that rifle. This way you won't have as much neck tension to hold the bullet. Seat the bullet only a little bit into the case, this way you will push the bullet into the case once it contacts the rifling. Remove the dummy carefully so as not to pull out the bullet and there you have the length from bolt face to rifling on your rifle WITH THAT BULLET weight and manufacturer. Measure overall length subtract the distance you want to be away from the rifling for your col.
 
Rather than 1/10th of an inch, perhaps you are talking 1/100th of an inch.
Seat a bullet so it will definitely contact the lands, and chamber that round, then measure the resulting round that has been seated to the lands. That process should be completed twice more with different bullets.
Using the shortest of the dummie rounds, run that round to the full extension of your press.
Now screw your seating ddie into the press. Screw the seater back so there is no contact with the bullet.
Gently advance the seater until contact is made. Remove the dummie round, and measure it so you know you have not seated the standard deaper. This can happen if you press cams over centre.
With the seater set, load one round and measure.
Keep advancing your seater until the bullet is seated 0.010 deaper than the dummie.
Mark your dummie round and store it with the bullets in the box.
Works for me.
 
iceman2 said:
Build your dummy load using a partially sized case fired in that rifle. This way you won't have as much neck tension to hold the bullet. Seat the bullet only a little bit into the case, this way you will push the bullet into the case once it contacts the rifling. Remove the dummy carefully so as not to pull out the bullet and there you have the length from bolt face to rifling on your rifle WITH THAT BULLET weight and manufacturer. Measure overall length subtract the distance you want to be away from the rifling for your col.
Click to expand...

This is exactely the way I have found easiest to do.
Only thing to add is I repeat the process 3-4 times to make sure I get an accurate measurement. Occasionally a bullet will hang in the land pull slightly back out of the case giveing a false reading, repetition eliminates that.
 
Which is why it's easier to measure the distance from bolt face to bullet tip using your cleaning rod inserted in the bore from the muzzle. Just measure from bolt face to muzzle, mark the cleaning rod, then drop a bullet into the chamber until it stops on the rifling. Measure from bullet tip to muzzle and mark the cleaning rod. Measure the distance between the two markings, and that is the max OAL for that cartridge using that specific bullet. Then you take that individual bullet and lightly twist it against the rifling at the muzzle and measure between that inscribed mark and the tip of the bullet to get the difference between OAL to the bullet tip, and the distance from the bolt face to the lands.
 
Bullet Comparators save all kinds of time and fiddling.

Since chamber length will change with use, you'll need to remeasure from time to time... Definitely worth the investment.
 
I use a hornaby OAL guage to determine the proper lenght to the land of the barrel and then use a Hornaby bullet comparator. Only problem i have run into with my 22-250 x-bolt is that some bullets wont fit in the magazine, for they are too long if I try to seal 0.01" from the land, so I generally dont go over the recommended COAL. one example that these tools came in useful for was when loadinng , barnes 36 gr varmint granades for COAL from Barnes website and from Lymans 49th are different, this really helped me out in deciding what COAL to go with.
 
Jordan Smith said:
Which is why it's easier to measure the distance from bolt face to bullet tip using your cleaning rod inserted in the bore from the muzzle. Just measure from bolt face to muzzle, mark the cleaning rod, then drop a bullet into the chamber until it stops on the rifling. Measure from bullet tip to muzzle and mark the cleaning rod. Measure the distance between the two markings, and that is the max OAL for that cartridge using that specific bullet. Then you take that individual bullet and lightly twist it against the rifling at the muzzle and measure between that inscribed mark and the tip of the bullet to get the difference between OAL to the bullet tip, and the distance from the bolt face to the lands.
Click to expand...

I used to do it this way, also.
As well, I used the method described by iceman.
Then, I decided that with any sporting rifle that was normally going to be fired by holding the rifle in my hands, it didn't matter two hoots in high hell, whether the bullet touched the lands or cleared the lands by a quarter inch, plus.
Just as long as it was short enough to feed through the magazine, not so long that it hit the lands so hard that the bolt wouldn't close and the bullet went into the neck a minimum of half a bullet diameter.
 
just set the sizing die for the length i want after using the same method as iceman2 and senior,and left it there regardless of bullet.since it was set on a longer/pointed style bullet(v-max) all of the bullets i use will chamber without hitting the lands.all rounds seem to shoot well with that setting as well.
 
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