|
Forum Rules | Firearms Safety | Firearms Photos | Links | Library | Lost Password | Email Changes |
Register | FAQ | Calendar | Search | Today's Posts | Mark Forums Read |
|
Thread Tools | Search this Thread |
February 24, 2009, 12:38 PM | #1 |
Senior Member
Join Date: February 18, 2009
Location: SE Michigan
Posts: 558
|
Bullet depth-include/exclude boat tail chamfer?
I'm getting ready to reload for the first time and will be seating 70gr Nosler BT into .243. For my first rounds I want to seat .243" of bullet but my Noslers have a boat tail chamfer on the back that's roughly .060" wide.
Would I want to seat just .243" or .303" to allow for the chamfer? Thanks. |
February 24, 2009, 03:16 PM | #2 |
Staff
Join Date: March 4, 2005
Location: Ohio
Posts: 21,060
|
You want to seat the bottom edge of the bullet bearing surface to the one caliber depth, if you are trying to follow the old rule of thumb that there is usually a good seating depth accuracy spot there? See this thread. I posted an illustration of bullet nomenclature there in post #20. I've put it up on this forum before, too, but I've forgotten where? You'll want to adjust that depth until you find minimum group size, then adjust the powder charge to tune it in still tighter.
__________________
Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle |
February 24, 2009, 05:21 PM | #3 |
Senior Member
Join Date: December 3, 2002
Posts: 1,264
|
"One caliber's depth" is something you would eyeball to ensure you've got enough neck tension to keep the bullet from falling out (assuming your case necks are correctly sized). You don't need to measure it down to three significant digits. 0.050" isn't going to matter really from that respect.
Your loading manual should give you an overall length for the bullet you've chosen. I wouldn't go blindly seating bullets blindly past that length unless you know for sure they aren't going to get stuffed into the rifling when you chamber the cartridge. Bullets seated too long (into the rifling) can give you excessive pressure issues. Before you go out on your own for seating depth, you'll need to either do some measuring with the appropriate gages, or you'll need to do some trial and error to find where the lands are for that particular bullet (stuff cartridge into the chamber--if it doesn't fall out from gravity alone, it's too long). |
Thread Tools | Search this Thread |
|
|