finding chamber length

[Kyle87]

hey guys just wondering if it would cause any damage to my gun if i would lightly run a fired brass into a neck sizer so that there is a small amount of resistance when inserting a bullet and chamber the round so that it comes into contact with the land. would this give me my chamber length? will it be accurate?

 

[AZShooter]

It would be hard to tell if the bullet moved to seat against the rifling depending on the neck tension. Why not seat a bullet in a normally sized case and look at engraved marks? Steel wool the surface of the bullet, the marks will be easily seen. Then progressively seat the bullet deeper till the marks are barely visible. You can reference from that and seat from that distance. To be frank there is no magic place to seat a bullet. You read of guys saying they prefer to start .010" or .015" away from rifling but the actual distance can vary.

Try your pet distance fromn rifling then do a series of bullet seating depths in small increments to try and find the best spot.

One time I took a 308 win and progressively moved the bullet deeper into the case in .002" increments to show a friend there can be more than one sweet spot. How far were they from the rifling? Don't know as I didn't use a stony point tool. Just referenced from small rifling engraving marks backwards. (ignore the numbers they were some sort of reference for me which I have since forgotten)

 

[rscott5028]

+1 with azshooter

also, you can color the bullet with marker, sharpie, or layout blue to help spot the engraving made by the rifling

also as pointed out, the exact distance isn't as important as finding the seating depth that consistently yeilds the best results

-- richard

 

[g0rd0]

It wouldnt hurt to neck sise as mormal then lube the inside of the neck. The lube will help your bullet enter the neck when chambered. And yes it will give an accurate measure of your chamber to land

 

[FUBAR]

Your headspace will be included in the OAL measurment, and like other methods, you need to do it for each thype of bullet....

 

[rscott5028]

Your headspace will be included in the OAL measurment, and like other methods, you need to do it for each thype of bullet....

OAL and seating depth are related. But, they basically have no relationship to headspace.

Perhaps you're referring to bullet jump/jam?

-- richard

 

[FUBAR]

I was assuming he was using his bolt, if he does then he still has a head space distance in the measurement and if he doses not use his bolt, different types of projectiles will give him different measurements.

 

[rscott5028]

I was assuming he was using his bolt, if he does then he still has a head space distance in the measurement and if he doses not use his bolt, different types of projectiles will give him different measurements.

Sorry.

I missed your point, but see what you're getting at now with the ejector plunger forcing the cartridge forward in the chamber vs other tools that don't even use the bolt.

The good news is that you don't have to have a precise measurement. You just need a relative starting point and safe load workup to find the seating depth that works best for your rifle/load.

-- richard