6XC, Reloder 16 and Berger 109

[J.d. Popkes]

Yes, my idea is seat your bullet just in the plus side and work up to pressure over a chronograph. Probably won’t go past 40.5/40.7ish with 107’s. Know your max, look for a flat spot in velocity while going up .3 at a time. Once you know your max or see a flat spot between charges shoot groups. Then tweak seating. I think the xc likes to be ran hard and like to know the ceiling even if it doesn’t shoot there.

 

[EdHarley]

I will try that, thank you. Still waiting on my 6xc case Length gauge brass to measure base to ogive at the lands. In the meantime, I took a piece of spent brass and seated a bullet and removed it a few times. When it was fairly loose I seated it long and closed the bolt. Measurements averaged 2.221” base to ogive. Case length was 1.890. So freebore is.331? Seems long. I will repeat when I get the case length gauge but that doesn’t seem right.

 

[Hoot]

If you have a Hornady (Stoney Point) case length gauge and case for measuring different bullet's distance to lands, take a flat base bullet and put it in backwards. Insert the setup into your chamber and run that flat base out until it stops. Lock it down, remove and measure. If the flat base has some slight radius, I face it off in a lathe as square as possible for the most accurate reading. I make my own cases for my length gauge. Bought the tap. Quick operation using a lathe or drill press.

Hoot

 

[EdHarley]

Wouldn’t the flat base diameter be larger than the ogive? If so do you add any length to your measurement?

 

[Hoot]

Wouldn’t the flat base diameter be larger than the ogive? If so do you add any length to your measurement?

That suggestion was to determine how much actual freebore your chamber was cut with, not to be confused with how much any specific bullet has to be seated to reach the lands.

Hoot

 

[EdHarley]

Got it. Makes sense. Thank you.

 

[J.d. Popkes]

I will try that, thank you. Still waiting on my 6xc case Length gauge brass to measure base to ogive at the lands. In the meantime, I took a piece of spent brass and seated a bullet and removed it a few times. When it was fairly loose I seated it long and closed the bolt. Measurements averaged 2.221” base to ogive. Case length was 1.890. So freebore is.331? Seems long. I will repeat when I get the case length gauge but that doesn’t seem right.

Fairly certain ya ain’t gotta 331 freebore

use the wheeler method.

 

[EdHarley]

Yeah, I don’t believe it either. I think the bullet pulled out of the case some during extraction. Will try it a different way.

 

[EdHarley]

If you have a Hornady (Stoney Point) case length gauge and case for measuring different bullet's distance to lands, take a flat base bullet and put it in backwards. Insert the setup into your chamber and run that flat base out until it stops. Lock it down, remove and measure. If the flat base has some slight radius, I face it off in a lathe as square as possible for the most accurate reading. I make my own cases for my length gauge. Bought the tap. Quick operation using a lathe or drill press.

Hoot

What is the tap size for making your own cases? I read once it is an unusual size - 5/16 - 56 or something like that.

 

[TAJ45]

5/16-36???? Just a whisp of memory on the 36. Wouldnt even bet slightly used TP on that recall.

 

[EdHarley]

I’ll see if I can find it and match the threads

 

[Lone Hunter]

I’ll see if I can find it and match the threads

The tap is 5/16"x36 TPI

 

[EdHarley]

The tap is 5/16"x36 TPI

Thank you

 

[Hoot]

I believe I got my tap from Ebay for around $8-9 shipped. Give a man a fishing rod...

Hoot

 

[EdHarley]

Awesome. Oh, what size drill bit do you use?

 

[Hoot]

I use a Letter L drill. A hair too big but close enough for the girls I go out with. If you have a limited drill set, a 9/32 will work. Its a hair too small but brass is ductile.

Hoot

 

[J.d. Popkes]

I have the tap and bit. What’s the best way to hold the brass while drilling and tapping? That’s always been the challenge, if you distort your brass where it won’t chamber perfectly then ......

 

[Hoot]

I have the tap and bit. What’s the best way to hold the brass while drilling and tapping? That’s always been the challenge, if you distort your brass where it won’t chamber perfectly then ......

I have done it with a drill press and lately have been using a 4-jaw lathe for truer hole centering. Either way, it doesn't take much clamping force to immobilize the case if you use several drill steps leading up to the final one, blowing out the chips along the way and of course, applying some cutting oil after every blow out. Ditto with the tap. I don't try to do the tap in one plunge, rather using the old school "two steps forward, one step back", blowout, repeat. If you want, you can overlay the case with a layer of tape to give the jaws something to bite into that is softer than the case brass. I used Kapton tape but box tape would probably do just as well. I did that the first couple of cases I did but came to the conclusion that it was not necessary if I didn't horse it. The hole doesn't have to be precision centered as there is slop in the threaded gauge shaft anyway. A reasonable effort at centering it is more than adequate.

Hoot

 

[EdHarley]

Sounds good. I have read that some use a Wilson case holder in a vise to hold the case. That won't be as good as a lathe but maybe they will fit in the clamps.

 

[EdHarley]

OH, I tried to flatten the base of a bullet the way you described, Hoot, and since I don't have a lathe I learned a way not to do it. I put it in pliers and tried to grind it off. The grinder, as you probably guessed, tossed that sucker across the barn. I would have liked to know the velocity of it.