Another seating depth question

[BlackEagle]

I am loading Berger 185 LRBTs for a 308 Palma chamber (not the 95 Palma chamber.) I have been trying to figure exactly what overal length is going to contact the lands. I removed the firing pin and I have been seating bullets in empty cases then marking and chambering them. The problem is I seat a bullet and chamber it and there are no markings then I'll seat a bullet 0.01" longer and I get triangular marks approximately 0.03" long where the bullet is making contact in the throat. How do I figure out where the bullet is jammed and where it is jumping?

 

[ordnancemarine]

you can save a lot of time and trouble by simply buying the Stoney point/ hornady OAL gauge. I know you may want to save some money by doing it that way, but it will benefit you more in the long run to get the proper tools for the job. That tool is one of the most indispensable necessities of my reloading bench. trust me, you won't regret it.

 

[alf]

I just use a Bic lighter and smoke the bullet.

 

[TheSnake]

I just use a Bic lighter and smoke the bullet.

Alf, your bullets are smoking before and after they leave the barrel!
Sorry, I just couldn't resist...

 

[BlackEagle]

I just use a Bic lighter and smoke the bullet.

That is very similar to the triangular marks I'm getting. If you have 6 of those marks that are roughly 0.03" long then would you say the bullet is jammed 0.03"?

 

[alf]

I guess I don't worry about the exact measurement. I try to start with a square mark on the bullet and go from there.

You're really just looking for a repeatable reference point to start from. From there, there's only one direction to go.....

 

[fguffey]

Again, I drill the flash hole/primer pocket to a diameter that will accommodate a cleaning rod, I then seat a bullet that is to be used for loading, the depth of the bullet is to be seated deep enough as to avoid the rifling before the shoulder contacts the shoulder of the chamber, after chambering the test round, I push the bullet out of the case with a cleaning rod until the bullet contacts the rifling (if the bullet is pushed out of the case before the bullet contacts the rifling get a longer bullet, if that does not work, work up 200 + rounds in groups of 5 and head to the range to determine what narrow window of combinations of loads the rifle likes, there will be a few bullets with starting loads that shoot good but will not shoot better by increasing or decreasing powder charge or by increasing or decreasing the design or weight of bullet) And I was asked why and how something like that could happen and I say/ask to see the reamer and the answer was “we broke it, by accident” and I say someone heard about Weatherby’s and the long throats, instead of saying “interesting, very interesting” they purchased a neck reamer and got after it.

Back to pushing the bullet out of the case with bullet hold, after removing the test case from the chamber it becomes a transfer, the transfer does not need to be placed into a Hornady/Sinclair, home made dial caliper with a round hole in it, BUT! if the transfer was placed into the Hornady/Sinclair, Home Made devise, what would the reloader do with the measurement? The measurement needs to be transferred to the seater die, there is no harm in looking at it, I suppose, the point being the Hornady/Sinclair, dial caliper home made devise with the hole in in from Home Depot is not necessary, nice? Yes, just not necessary.

Again, all I want to know is ‘Where are the lands? What is the distance from the bolt face to the lands and it is not OAL or COL, or COAL, after determining measurement from the bolt face to the rifling with the transfer, I place the transfer in the shell holder, raise the ram then adjust the seater down until the die/crimp contacts the mouth of the case, then stop, back the die off 1/2 turn then secure the die to the press with the lock ring. After securing the die to the press I adjust the seater stem/plug down until it contacts the bullet, then stop and secure the stem/plug to the die with lock nut on the stem. THEN I use a height gage or dial caliber to measure the height of the stem above the die, after measuring the height of the stem above the die, I adjust the dial caliper to .000 and call it .000/zero off the lands, again without a Hornady/Sinclair or home made too,

After adjusting the seater stem for .000 I use the .000 as an Index (write it down) then lower the stem and measure from .000 for seating bullets off the lands. Example, if I decide the adjust the bullet .030 off the lands I would use the dial caliper to adjust the seater stem from the .000 index .030 thousands, not forgetting to secure the locking nut on the seater stem/plug.

With bullet hold, the transfer can be stored for future use, again, my rifling contact point does not move, on my 30/06 chambers the contact point is always between .300 and .308, but that is for another day, so if you choose to use cases with sized neck in any combination you choose, it is OK with me.

F. Guffey

 

[swt5]

A few things I've found that greatly improve the repeatability of attaining my COAL measurements is removing the ejector from the bolt while doing this. A light touch of oil on the ogive/bearing surface then gently pulling the bolt straight back out of the receiver with the cartridge. A quality micrometer seating die removes the PITA of playing with a seating stem to achieve .0015 seating depth variances and is worth it's weight in gold. JMTC

 

[gilream]

I just use a Bic lighter and smoke the bullet.

I tried that once but it made me cough something fierce! (sorry)

 

[alf]

Worse than smoked carp........?

 

[Outrider27]

Smoked carp? Good grief!

I'm low tech; always used a wood strike anywhere match. We'll have to try the Bic; always keep two or three around in case of an emergency, as they are much more reliable than rubbing a Boy Scout and a Girl Scout together, or whatever it was they used to teach us back when for starting a fire in an emergency....

 

[Catfish]

I think your really looking for the wrong thing. Different barrel like different jumps or no jump at all. Once you have something close why no just load some ammo and try it. Then load some .005 longer or shorter and try those untill you find what your gun likes. I have some rifles that shoot best with the bullets seated .030 into the lands and others that like about that much jump. Load what the rifle shoots best and don`t worry about where the lands are.

 

[fguffey]

I think your really looking for the wrong thing. Different barrel like different jumps or no jump at all. Once you have something close why no just load some ammo and try it. Then load some .005 longer or shorter and try those untill you find what your gun likes. I have some rifles that shoot best with the bullets seated .030 into the lands and others that like about that much jump. Load what the rifle shoots best and don`t worry about where the lands are.
[/Iquote)

have no clue what others are looking for, I want to know where the lands are located in the form of a value like ‘HOW FAR from the bolt face’ because I am the fan of bullet jump, I want my bullets to have a running start, to jam the bullet into the rifling .030 thousands could lock everything up, my bullets must get out of the way because of the expanding, hot-high pressure metal cutting gas, for most all that is required to accomplish this is pull the trigger, but, in my mind ‘time is a factor’ as in what happens if there is not enough time for the bullet to get out of the way before the hot high pressure metal cutting gas exceeds the ability of the receiver/case head to hold the pressure because the bullet seated into the lands acts as a delay or an obstruction. And for that reason I have nothing to gain by seating the bullet to or into the lands just because I can.

All of my seater dies are adjustable in thousands, the dial indicator mounted on some dies are nice, not necessary, just nice, and again I want to take a measurement from the chamber to the die and back to the chamber, again I have a choice as to seating off the lands, I also have a choice when choosing methods and techniques. methods and techniques with tools I own and understand, or purchase more tools for more money, for what, back to the big inning, all I want to know is ‘the distance from the bolt face to the lands’ for a bullet I am loading.

F. Guffey