28 February 2008, 18:22
Red C.Minimum bullet seating depth for sound mechanical fit?
I know there are minimum overall cartridge lengths given for most loads, but I was wondering if there was a rule of thumb for how deep into the case a bullet needs to be seated for it to have a sound mechanical fit. Seems that I read somewhere that the caliber/width of the bullet was a good rule of thumb for minimum seating depth. This comes into play when using light bullets and still trying to have it close to the lands.

28 February 2008, 19:34
buckshotThis is where a specialty die like the Redding "S" die could help. Provided the reloaded cartridge isn't a sloppy fit in the chamber when done, I believe .001" or .002" difference in neck tension would matter little if one annealed the case necks. Too much movement when resizing will serve only to work harden your brass shortening its service life.
28 February 2008, 19:36
Gary SurkoI think the old rule is 1 caliber depth
29 February 2008, 01:03
fredj338quote:
Originally posted by Gary Surko:
I think the old rule is 1 caliber depth
That's my minimum. Any less & you are likely to loose a bullet to handling in the field.
29 February 2008, 03:02
Hot Corequote:
Originally posted by Gary Surko:
I think the old rule is 1 caliber depth
Hey Red, I went with that same line of thought for a lot of years and never had any problems, because I was always deeper than 1-caliber.
Then a good number of years ago I began Testing 120gr and 130gr Boat Tail bullets in a 7mm-08 M7. If those Bullets are Seated out near the 2.800" magazine limit, there is less than 1-diameter of the Bullet in the Caseneck. Closer to 0.100" than 0.284".
I thought about it for awhile and went through my normal Hunt preparation process. I carry the cartridges afield in plastic boxes, so there is no opportunity for them to be knocked loose inside the box. Then they go directly from the box straight into the magazine, plus one in the chamber, so there is no chance for them to be knocked loose then.
But occasionally I'll put the one from the chamber into my pocket, and there is a good opportunity for it to be knocked loose there. So far, no Bullets have fallen out of those Cases, but I would not argue with anyone who says they have experienced it.
Normally speaking if you use mid-weight and heavy for caliber Bullets, it is a non-issue. That is because they are typically Seated deeper than 1-caliber to clear the magazine and lands. Even more so with the newer Super Sleek, high Ballistic Coefficient Bullets.
Best of luck to you.
29 February 2008, 04:36
Ol` JoeI`ve always tried to keep with the "one caliber" rule when seating bullets. The problem with this "rule" though is there are more then a couple cartridges with necks shorter then the caliber. The 223 Rem, 260 Rem, and 300 Win mag come off the top of my mind.
I don`t really know if seating can be ruled by a "std min" or if one must seat and test the integrety of every cartridge to establish a valid min.

29 February 2008, 09:06
Allan DeGrootI don't think there is any "Carved in stone" rule
but I personally like a minimum of one caliber myself.
AD
29 February 2008, 17:31
1894mk2I go down to 66% and have not had problems. I don't care for my ammunition much either. Depends to an extent on how much is out front - a 140gr 6.5 needs more in the case than a 70gr 243 as there is more of a turning moment on the exposed bullet.