Determining COL for K31 chamber

[fenelon]

Rookie loader here again, after doing some more reading. When determining length to ogive on a particular round that you're going to reload:
- is it worth buying the Stoney/Hornady OAL straight guage and modified case to do this measurement, or does the "hillbilly" method work OK (use fire-formed case, deprimed, with bullet lightly seated in the case).
- once you get the length figured out for that particular bullet/case combo, how far "back off" do you start with ?

Thanks,

Dave

 

[klink1983]

I'm a newbie as well. A buddy of mine at work (sniper) showed me this trick. In talking with other people, I get very similar explanations with slight variations on preparing the case but it's pretty self explanatory.

1. Take an old piece of brass, and hacksaw 2 cuts into the neck. It should be snug, but loose enough to pull out a projectile with your hands.
2. Chamber said riggins with a projectile a minimum of 5 times....GENTLY, each time measuring the OAL of the completed riggins.
3. Calculate mean average, use your judgement based on your results to seat how deep or long you wish to.
4. Make a "template round" using a piece of brass and sacrificing one projectile. This is used to setup your die.
4.a Seat the round in your press
4.b Insert die, loosen off seating riggins
4.c Stroke your press..... lol
4.d Screw in seating riggins back into the die until it makes contact with your template round
5. Die is setup for YOUR custom OAL requirements.

In my case my magic number is 2.83" and I have templates made up for each projectile that I reload...with the measurements clearly indicated. I also have a template if I am loading to factory specification in the event that I could be sharing ammunition with someone else.

All I can say is do your research!! There is no such thing as redundancy in safety. When in doubt ask..... or cruise around on the forums and you will find help!

 

[(((Echo)))]

Rookie loader here again, after doing some more reading. When determining length to ogive on a particular round that you're going to reload:
- is it worth buying the Stoney/Hornady OAL straight guage and modified case to do this measurement, or does the "hillbilly" method work OK (use fire-formed case, deprimed, with bullet lightly seated in the case).
- once you get the length figured out for that particular bullet/case combo, how far "back off" do you start with ?

Thanks,

Dave

I have the Stoney Point gauge, but no modified cases. Gonna make the ones I need. Sounds easy enough to do, and guarantees a better fit to your rifle.
I used the "hillbilly" method when making rounds for my K31, and it worked OK. I backed the bullet .020" off the rifleing. Others may chime in here, but I don't think there's a carved in stone number that you must adhere to.

(E)

 

[klink1983]

I used the "hillbilly" method when making rounds for my K31, and it worked OK. I backed the bullet .020" off the rifleing. Others may chime in here, but I don't think there's a carved in stone number that you must adhere to.
(E)

Its probably just personal preference. I know for me, I feel skiddish when I am right on 2.83 or over just because of the likely hood of problems chambering rounds.

 

[Tinman204]

I have the Stoney Point gauge, but no modified cases. Gonna make the ones I need. Sounds easy enough to do, and guarantees a better fit to your rifle.
I used the "hillbilly" method when making rounds for my K31, and it worked OK. I backed the bullet .020" off the rifleing. Others may chime in here, but I don't think there's a carved in stone number that you must adhere to.

(E)

I find that .020" is a good safe place to be. But that being said some of my guns like more room like .025"-.030" and others like the bullet to crowd the lead but I do this very carefully.

Like stated above, you can never be too safe and never ask too many questions!! The more questions we ask the more we learn!