Reloading Question

Joined
Feb 11, 2016
Messages
368
So I am starting to reload. I'm working with an older .243 savage to get my feet wet. I measured the COAL by placing a bullet into once fired brass from my rifle. Did the sharpie trick 10 times and averaged out the overall length to be 2.761. Bullet was definitely contacting the lands as bolt was stiffer to close. I know this method has its downfalls as well because the bullet could possible be pushed thousands of an inch into the lands when closing the bolt, measurements are not exact (hence the need or recommendation for an average), etc. I don't have an overall length gauge and I wanted to play around to see what results I would get.

At 2.761 overall length if I back off 0.015 as a start for bullet seating depth to use in a ladder test then I get 2.746. Max overall length according to SAAMI is 2.710. I know SAAMI is made for ammo to work in all rifles. Is it typical to see a 0.035 difference if your chamber vs max SAAMI spec?

Should I start ladder test at max SAAMI spec or should I consider my rifle's measurements a better starting point?

I did make a dummy round at 2.746 and it chambered with no difficulty at all.
 

Fire_9

WKR
Joined
Dec 29, 2015
Messages
402
Location
Lewistown, MT
Don't worry about what overall length you see in a books or what other people post for their rifles. You're on the right track and use what overall length your rifle likes/needs.
 

V65Magna

FNG
Joined
Jan 13, 2018
Messages
87
Location
MD
I would consider your rifles measurements a safe starting point. If you are between .010" and .030" off the lands you should be fine. I always use Cartridge Base to Ogive (CBTO) measurements for developing my loads and usually start at .020" off the lands. Start at the lowest charge if the gun is new to you and work your way up to the charge where you want to start your ladder test. To avoid loading too many rounds below where you want to start the ladder, I just load a single "check charge" at .5 grain increments from the lowest published charge and watch for signs of pressure on the way up.

Consider getting a Hornady OAL gage and bullet comparators when you get a chance. A very helpful tool to have handy!

Good Luck. The .243 is a fantastic cartridge!
 

rayporter

WKR
Joined
Jul 3, 2014
Messages
4,251
Location
arkansas or ohio
all bullets and brands are a different shape thus the problem you have. so yes there can be a large difference in these lengths. measuring to the tip is just a crap shoot.

if you can save one bullet to use for measuring you can help mitigate that. sammi lengths may be for a magazine, too.

do the sharpie thing a few more times as you seat the bullet farther and farther from the lands to see where you get the point of not touching the rifling.

it has been years and years since I even noticed sammi lengths.
 

N2TRKYS

WKR
Joined
Apr 17, 2016
Messages
3,954
Location
Alabama
I prefer the COAL measurement to the measurement to the ogive. I use a cleaning rod to find my distance to the lands. I do this for safety purposes only. I don't have any desire to chase the lands. I'm loading for hunting rifles, so mag length is more important to me.

Just worry about the measurements for your rifle.
 
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