Best tool to measure base to ogive

cw308,
I mean no disrespect by this at all, but I wasn't aware you had a 'System' or even method of measuring the ogive contact point. You mentioned 'The Nut' which is a random, generic comparator adapter.

I thought you were asking how to specifically measure YOUR chamber so you could find YOUR Chamber to bullet contact diameter on a specific bullet shape.

Defining the issue, you MUST know precisely what the diameter of your chamber throat is.
A bullet in an extension works to find that diameter.
Epoxy a bullet on a wooden dowel rod, epoxy or solder one to a piece of tubing, set/crimp one REALLY LONG in a case, doesn't matter as long as the bullet reaches the throat.

Plug that bullet into 'The Nut' and see where your actual bullet profile lands...
You might get lucky and 'The Nut' is correct, or 'Close Enough'.

Without the actual throat diameter with the bullet you are wondering about, since it's a taper on a taper, you won't know.
Once you have that diameter off the test bullet, you can make a REALLY CLOSE guess with all other bullets since the taper on .308 bullets doesn't change a crap load unless you start shooting round nose!

'The Nut' will be fairly close, but it's not YOUR chamber...
 
I use the Hornady Lock-N-Load system, and for how I shoot, and for how I reload, it works fine. The system I have is the bullet comparator with the basic insert set (.224, .243, .257, 277, 284 and .308). My interest lies in good hunting ammo, and I'm not terribly concerned about making one hole groups with any of my rifles; if I hit the same hole twice (or more) whilst shooting for group over my daypack, GREAT! I just want good ammo that's going to work through the action with good hunting accuracy when that moment of truth comes along in the field. I am completely confident with my hunting reloads, and have been successful enough in the field to say so.

The other tool that goes with the comparator set is the Hornady straight O.A.L. gauge. This uses a modified case for each/any caliber you want to make measurement on, and it too, works very well for me. I used to do the bullet marker bit, but always found it wanting for a better way. I have it now. You just put what bullet you want to use in the modified case, insert/chamber the tool, move/slide the bullet forward 'till it touches the rifling, lock the tool, back it out and measure with the comparator set (you MAY need to lightly nudge the bullet out of the rifling with a rod after extracting the tool). Measure your free bore to wherever you want it, and your done; set your seater die accordingly. Whenever you change to a different weight bullet, you just run the system to measure the new specs on the new bullet. Easy, and safely accurate (IMO).

I pretty much use Hornady bullets in all three of my '06s, my 6mm Rem. and my .223. Generally, if I'm looking to buy bullets, and if I see on the shelf that there's a couple of boxes that are of the same lot, I'll buy them both, and use the Lock-N-Load tools without any thought as to ogive consistency. I figure the ogive on the 200 pills I just purchased should be fairly consistent. Anyway, I like the Hornady system very well to measure the proper C.O.A.L. on my reloads (as I use them). These days, my .223 bolt gun gets shot the most.

Though I haven't used it yet on any "testing," I did buy a modified case for my two M336s. It'll be interesting to see what kind of free bore they have if I decide to try a "custom" 30-30 load. They might have to be fed singly in those old Marlins.
 
I tried an have the Hornady Lock - N - Load thought it wasn't so precise .I like using a stripped bolt seating the bullet long , going through lowering the seat until the bolt closes without any resistance. Where doing the same thing , only I'm using my bolt . It does take time but I find it dead on . I use a case with .001 headspace . Found the same way as ogive setting .
 
JeepHammer
I think your mixing me up with someone else . I never used that hex nut , I know of it but never gave it a try . The comparator I do have but found the PM Mic easier and I double check with the comparator . Even measuring powder with the RCBS ChargeMaster 1500 I dump that charge into the pan on the GemPro 250 scale . I take my time I'm only loading 30 rounds of 308 to shoot every Sunday weather permitting . My rifle is blueprinted , so I only blame myself if my groups open up . 2500 rounds down the second barrel ,
 
OK with me, sorry if I confused you with someone else.
I don't shoot bench rifles much anymore, I'm down to one, and I have the load worked out for it.
I do usually get an idea of the throat opening diameter when I'm building a rifle, most people ignore it anyway so it's no deal.
Since I make the case/round gauge out of the excess barrel the gauge is usually within 0.001" or less of what the actual chamber is, but that's before you hammer the throat with bullets.

Unless you are trying to get a specific distance off the lands, it's usually just seating the bullet long and letting the bolt push the bullet back to zero. Once chambered, you simply eject and measure and set your bullets from that point minus what ever freebore you want. (Bullet jump, or what ever people are calling it today).
 
JeepHammer
I tried soft seating an remove the case an measure , the problem the rifling would grab on the the bullet an pull it out slightly every time . You can cut steel , I have enough problems with wood . Easier to buy those mindless tools . Thanks for all you help full information . Respectfully.

Chris
 
JeepHammer
I tried soft seating an remove the case an measure , the problem the rifling would grab on the the bullet an pull it out slightly every time .

Too much time is wasted on trying to prove 'it can be done'; I have never been a fan of squid neck cases, I am the fan of 'all the bullet hold I can get'. With bullet hold I am not required to start over the next day and the day after that etc. etc..

F. Guffey
 
Simply remove extractor and open bolt, the test round will be left in the chamber with no extractor.
Then you GENTLY push/tap it loose from the rifling with wooden dowel rod or brass tipped cleaning rod.
(Never stick anything steel down a barrel from the muzzle)
Don't hit it harder than needed to dislodge the bullet and the case/bullet will come right out without moving the bullet in the case.

Don't know if it will work for everyone, but the last time I did one, I wedged a bullet into the plastic end of a chamber protector and got the ring on the bullet.
Not all chamber cleaning adapters will have the right size plastic nipple on the end, this was just a fluke, but it might work for someone...

As for the adapter being metal, who says it has to be metal?
A good hard wood that's really dry would work, but would swell with humidity.
Hard synthetic is rigid enough for measuring force, and works as easily as wood.
Derlin comes to mind immedately.
 
Simply remove extractor and open bolt, the test round will be left in the chamber with no extractor.
Then you GENTLY push/tap it loose from the rifling with wooden dowel rod or brass tipped cleaning rod.
(Never stick anything steel down a barrel from the muzzle)
Don't hit it harder than needed to dislodge the bullet and the case/bullet will come right out without moving the bullet in the case.

A waste of time; a reloader with shop skills and a fundamental understanding of transfers would have the project under control and finished.

And bullet hold: it helps if the reloader is a fan of bullet hold, I am the fan of bullet hold; I want all the bullet hold I can get.

F. Guffey
 
A waste of time

Kind of what I was thinking after 49 posts.

“Best tool for making relative measurements from an irregular sufface to a flat surface”, would be a better title.
 
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Read articles on soft seating . If your sizing your necks with bushing dies , with light neck grip I can see it work to seat to ogive but with a jump I found with a .003 of grip on the bullet seating down you can feel when the bullet is off the lands . We're dealing in thousands of differences , more precise then store bought , most of the time it's enjoyable.
 
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