Determining bullet seating depth

[gobbler]

I don't reload alot of different rifles or bullet sizes. When I find something I like I will stick with it. I have been loading a 270 130gr BT for my REM700 with 58.5 gr od H4831SC. Shoots good. The way I determined the OAL was using a marker a checking to see whn the lan marks went away. That's the way I was taught. I noticed the Nosler FAQ describes using an unsized case and marker and putting the case and bullet into the gun. When you remove it this will be your starting OAL or rifle seating depth. I was trying to work up a length for the Partition. I was not comfortable with my results. It seemed the cartridge was coming out to long. I went back to my initial way of determing the starting length and came out with a measurement very close to the 130 gr BT load I have always used. Does this seem feasible and compare with some of you guys results?
Thanks

 

[Ol` Joe]

Like you, I always had better luck with a smoked bullet then useing a unsized one as Nosler recommends. The best way I`ve found, and the one I rely on is the Stoney Point tool. It takes a few practice runs to get the feel for the tool but it works like a charm. The tool is cheap, although you need a "insert" for each caliber you load. IE; 264, 277, 284, 308 ect. It will quickly set your distance to the lands on any bullet you choose once you find the OAL your rifle preferes.

 

[bcd]

I also shoot a rem 700 and have a stoney point oal gauge and a bullet comparator, and last night I loaded some 140 grain accubonds for a friend that shoots a weatherby vanguard and according to the oal gauge and comparator my lands start .297 further than his.


weatherby 2.700

Remington 2.997


I was worried at first but then I checked some of my other loads (140 grain bt) seated for my chamber and they were consistent with these measurement, but they do look long, and there isn't much bullet left in the brass

 

[Ol` Joe]

I also shoot a rem 700 and have a stoney point oal gauge and a bullet comparator, and last night I loaded some 140 grain accubonds for a friend that shoots a weatherby vanguard and according to the oal gauge and comparator my lands start .297 further than his.


weatherby 2.700

Remington 2.997


I was worried at first but then I checked some of my other loads (140 grain bt) seated for my chamber and they were consistent with these measurement, but they do look long, and there isn't much bullet left in the brass

Every chamber is different. You`ll be lucky to find two rifles that like the same oal when you do fine two that have the same lenght to lands. Try measuring your barrel leade after shooting 500 rds and you`ll find it`s moved out farther.

One other thought, inre to the stoney point tool. The cases they sell and your chambers headspace may or may not match. You might find the same OAL in two different rifles with the factory case and be off a few thousanths in one of them as to true lenght to lead. The problem is the lenght from the bolt face to the point the shoulder hits the chamber shoulder (headspace) will also differ in various rifles. You measure the lenght from the point of shoulder contact to the leade with the tool not the true lenght from bolt face to leade as one would believe. This can be fixed by tapping a case fired in your rifle to fit the stoney point attachment. The differance in measurment is very small and really is moot as the lenght you finally decide on will repete with the tool and will relate to the bolt-leade relation in the end anyway. :? :?

 

[longwinters]

Ol Joe,

I also use the Stoney point guage, but I never thought of the potential difference in brass length. :idea: :idea: . It has worked out very well for me in 5 different calibers so I guess I have been a little on the lucky side.

The funny part is that with my last 2 new rifles, the clip is shorter than my chamber measurements so I have to determine OAL by the clip measurement. And both of these rifles shoot well under MOA. (1/2" - 3/4"). I am starting to think that chamber measurements are not as important as I once did, at least not for Sako rifles.

Long

 

[xray]

I like the Stoney Pt. case mod as well but have too many calibers....what I did is ream out primer pocket completely, then ream .22 cal. neck mouth all the way through with Forster .224, then FL size case. Bullets may now have a "slip fit" into neck mouth and for a bolt gun, chamber the cartridge, measure the OAL and that's a good place to begin measurements from. To remove bullet, I use a thin swab stick pushing bullet forward through the enlarged primer pocket opening. This case esp. designated for ea. caliber retained in die box.......