Minimum seating depth for bullet neck tension??

[theosmithjr]

I got some 140 Elite Hunters for my creedmoor but when touching lands only .376" of the bullet is in the case neck and approximately.200 of that is boat tail. I'd like to start off .010 off the lands so that would give me .386" of total bullet in the case back but with .200 of that being boat tail that only gives me .186" of the neck gripping the bullet. I'm sure that's not enough right? What is the proper minimum length of bullet grip!

The RULE OF THUMB for BULLET SEATING DEPTH is at LEAST the DIAMETER of the bullet you're loading.
Theosmithjr

 

[John Klingenberg]

I got some 140 Elite Hunters for my creedmoor but when touching lands only .376" of the bullet is in the case neck and approximately.200 of that is boat tail. I'd like to start off .010 off the lands so that would give me .386" of total bullet in the case back but with .200 of that being boat tail that only gives me .186" of the neck gripping the bullet. I'm sure that's not enough right? What is the proper minimum length of bullet grip!

Rule of thumb is one caliber depth minimum so .260 touching the neck.

 

[misterc01]

Read the following with a grain of salt (pun intended So, now I have seen three rules of thumb. 1. Min 1 caliber circumference depth. 2. 1/2 caliber circumference depth. 3. What ever stays in and does not pull out using finger pressure. Over arching rule: SAFETY. NOTE: the following data is valid only for MY rifle, reloading, measuring tools and informational use. The factors I took into consideration: Length of bullet bearing surface (grip surface for case), level of powder in case, Ogive distance from the lands, and Case neck tension (case grip force on the bullet.) My goal: a desirable distance from ogive to the lands, powder not compressed and a secure neck tension. So I used .02"-.03" from lands, .02"-03" neck tension and not compress the powder. I then marked a bullet at 1 caliber, 1/2 caliber, 1/4 caliber and 1/8 caliber distance. I then seated the bullet using a Lee collet die with .03 and then .02" neck tension. Long test story short - with either .03" or .02" neck tension, I could seat to 1/8 caliber depth and was not able to remove the bullet by hand. I also checked the bullet "grip" with Hornady concentricity gauge and was able to move the bullet with the adjusting screw to get it straight (concentric) and the bullet stayed where I put it. I did NOT fire at any of these tests measurements because this was just an exercise in curiosity. Now, in the real (range) world - I seat to not compress the powder, and stay at last .003 off the lands with acceptable accuracy. The bullet ends up seated into the case a little over a caliber circumference. I also only load and shoot a single round at a time. IMHO one should use THEIR rifle, tools and commons sense to determine what is SAFE for THEM! IF it does not feel or seem safe, then it probably isn't!

 

[John Klingenberg]

If you load less than the caliber depth you get a premature bullet release. The bullet then wedged into the lead and you get a massive pressure spike outside the case. Check for lots of powder burns around the case mouth if you decide to try the shallow seated ones. If you have powder burns down to the shoulder it will be one of two things...an under loaded case or too shallow seating.

 

[ar10ar15man]

just not true if you are close to the lands
rule of thumb is good for one thing
THUMBS

If you load less than the caliber depth you get a premature bullet release. The bullet then wedged into the lead and you get a massive pressure spike outside the case. Check for lots of powder burns around the case mouth if you decide to try the shallow seated ones. If you have powder burns down to the shoulder it will be one of two things...an under loaded case or too shallow seating.

 

[ar10ar15man]

JUST NOT TRUE UNLESS YOUR THROAT IS SO LONG IT LAUNCHES THE BULLET BEFORE IT HITS THE LANDS...WEATHERBY
not the rest of the world.

If you load less than the caliber depth you get a premature bullet release. The bullet then wedged into the lead and you get a massive pressure spike outside the case. Check for lots of powder burns around the case mouth if you decide to try the shallow seated ones. If you have powder burns down to the shoulder it will be one of two things...an under loaded case or too shallow seating.

 

[misterc01]

If you load less than the caliber depth you get a premature bullet release. The bullet then wedged into the lead and you get a massive pressure spike outside the case. Check for lots of powder burns around the case mouth if you decide to try the shallow seated ones. If you have powder burns down to the shoulder it will be one of two things...an under loaded case or too shallow seating.

 

[misterc01]

FYI an interesting note - was reading a post on another forum, and the shooter there was seating at 1/2 caliber depth at .01 off the lands and he had no problems at all. To me that says "you pays your money and you takes your chances~!" I prefer to be a little on the conservative side would NOT go less that one caliber depth.