How do I Measure Length
10-24-2007, 08:11 PM
#2
Nontypical Buck
Join Date: Mar 2004
Location:
Posts: 1,837
RE: How do I Measure Length
I took my rifle with the bolt closed and dropped a bore rod in it against the bolt face and put a line on the rod with a sharpie exactly where the rod comes out of the crown. Then I took a bullet and dropped it inside of the chamber and held it in place with a dowel rod held against it and put the bore rod back in the barrel and measured it again where it came out of the crown and put another mark on the rod with a sharpie and then I measured the distance between the two lines. This gave me my OAL to the lands if that is what your wanting.
10-25-2007, 09:36 AM
#4
Guest
Posts: n/a
RE: How do I Measure Length
Two best most accurate ways IMO up to .005" is to take a fireformed case that is neck sized onlyand split the neck with a dremel tool. Put the bullet in the case and close the bolt and slowly carefully remove. Measure on the ogive using a stoney point tool, not the tip. Do this for 3 bullets. You should see .002" or so consistency.
Another way is to use the stoney point OAL guage. Which is probably the most accurate. But a pain because you go to have fireformed case modified. I have checked both procedures against each other and find the split case method jammes the bullet in the rifling about .003" more than with the OAL guage. I just keep this in mind.
I have seen people try all kinds of other way by marking dowls and just trial and error with loaded ammo on if they can close the bolt. But none are accurate within .01".
A reloader needs to invest in tools.
Another way is to use the stoney point OAL guage. Which is probably the most accurate. But a pain because you go to have fireformed case modified. I have checked both procedures against each other and find the split case method jammes the bullet in the rifling about .003" more than with the OAL guage. I just keep this in mind.
I have seen people try all kinds of other way by marking dowls and just trial and error with loaded ammo on if they can close the bolt. But none are accurate within .01".
A reloader needs to invest in tools.
10-25-2007, 12:15 PM
#5
Nontypical Buck
Join Date: Feb 2003
Location: Body in SE WI, mind in U.P.
Posts: 4,781
RE: How do I Measure Length
A friend of mine has been coming over to my house to learn to reload. I showed him how do take the measurement with a cleaning rod. I sold a Swiss K-31 in 7.5x55 to him and Stoney Point/Hornady doesn't make a case guage for that case. He's very handy with tools (he's into drag racing), saw how my stoney point guage worked, and made a couple of case guages from materials found at the local Home Depot. I'll see if I can post pictures today or tomorow of the guage he made me- its very simple and it cost him about $6 in materials to make 2 of them. Its nice to buy a stoney point guage but they are like $35/ a piece.
10-26-2007, 08:01 PM
#6
Fork Horn
Join Date: Jul 2007
Location: Georgia
Posts: 364
RE: How do I Measure Length
The way I do it is to take a fired case and put a slight dimple in the mouth just enough to keep the bullit from slideing all the way into the case,next take a bullit and mark it with a majic marker and slide it into the case about a third of the way. Next chamber it slowly and close the bolt, open the bolt and extract the round, if the bullit stays in the barrel slide a cleaning rod down the muzzel and push it out. Where the scratches stop on the bullit were you marked it that is max chamber, back off 3 to 5 thousands off the lands and groovesand this is your OAL.
