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I have been reading what I can find about head space, but now I'm more confused. should I get a head space gauge for safety reasons or just use col from the data. also when seating I have been getting different col and i have noticed that some of the lead tips are flattened slightly and is the reason I think I am I am getting different col up to.015. I am loading for hunting
If a bolt action rifle has excessive headspace, and like your -06 fires a rimless bottleneck cartridge, you will notice it due to very short case life when full length sizing. This is due to stretching of the case web as the case expands each firing to fill an overly long chamber. FL resizing then returns the case to proper length but the brass that flowed forward ends up at the neck lengthening it beyond max length and requires trimming each firing. As the web thins it becomes weaker until the case head either partially or fully separates - you get the head in the extractor but the rest of the case is still in the chamber. To test for incipient head separation straighten out a paperclip and make a 1/8" right angle bend at one end. Use it to feel the inside of the case body - if it is smooth all around top to bottom, you're OK, but if you feel a catch (picture a valley parallel to the base) the case is dead. Sometimes but not always you can notice a bright ring around some or all of the case web, not to be confused with the "ring" left from the bottom of the sizing die, a separation ring is higher on the case. Often both ring and valley can be seen and felt, but sometimes only the valley, especially if you polish your cases. The condition is not necessarily dangerous, and can easily be dealt with by a handloader. To properly set a sizer to any specific rifle, all you want to do is to just bump the case shoulder back enough to easily chamber the case - if the rifle has a headspace issue, the die is set just a tad bit higher in the press than it would be normally. That will return case life to normal, and neck sizing helps even more. Think of it like you have a wildcat or "improved" chambering - you fire form the brass to your "custom" chamber and neck size until chambering it begins to get tight. Then you bump back the shoulder enough to get things working smoothly again, but not enough to return the case to the original factory specs. Usually such problems are only seen with any frequency in rimmed and belted cases, but occasionally you do find a rimless chamber that has some issues, especially in older rifles that have seen a lot of hard use.
As to your col question, just measure the ones with undamaged tips - the seater works by pressure on the ogive (curve) of the bullet, not the tip, so even if you get a different number with the damaged tips, the distance from ogive to lands is still the same for all. The tool to check thisd with is called a bullet comparator - it is just a piece of steel with a tapered hole into which the loaded round is inserted and it bears on the ogive, not the tip, and you measure the whole thing with a caliper and compare that measurement to either a factory cartridge or one that feeds and chambers properly in your rifle. Some folks like to seat rifle bullets as close to the lands as possible. Sometimes this greatly increases accuracy, sometimes not, and again sometimes when seated as far out as possible the resulting col is too long to fit the rifle's magazine and won't feed. Suggested col insures that the round will feed in most every rifle so chambered, but max or optimal col for a specific rifle can be and often is longer. How much difference this makes to a hunting rifle depends on the range and size of game – it can make a big difference to a long range varmint hunter, but may not be worth the effort for a big game rifle at 200yds or less.
Thank you very much for your quick reply. when you do the paperclip test do you do that after firing the case or after resizing?
You do it after firing. If the case is toast, then you don't have to waste your time prepping it.
I have one rifle that has a headspace problem. However with a bit of fireforming and then properly setting up the FL die, no more heaspace problem.
This is how I set up my sizing die for bottleneck cartridges which eliminates headspacing worries.
1. Take a once fired factory round and blacken the neck and shoulders with a Magic Marker or Sharpee pen. Some people like to smoke the neck and shoulder, but I find the Magic Marker/Sharpee pen a bit better.
2. Carefully lubricate the case.
3. Loosen the lock ring on the sizing die and back off about two turns from when the die is set to touch the shell holder.
4. Size the case. Note where the marks are on the case and turn the die down about a half a turn and size again. Turn down some more, and resize again. What you are looking for is the marks on the blackening just touching the shoulder.
5. Clean the lube from the case and try it in the rifle. It may chamber just a bit on the snug side. If so, turn the die down ever so slightly, lube and size again. Wipe off the lube and try in the rifle. If it slides in as easily as a factory round, you should be good to go. If not, usually one more very slight adjustment should fix the problem.
6. Tighten the locking ring for the die and you're done. You have just set your sizing die up for a custom fit to your specific rifle, rather than a generic one size fits all guns.
Paul B.
Thank you for all the info.