gomeybear wrote: ↑Fri Jan 10, 2020 4:31 pm
SIMJOSH1 wrote: ↑Fri Jan 10, 2020 1:57 pm
eh, IMO that's good info for every reloader on every bullet... That way you could play with it and know definitively where the max OAL is.
Some bullets could have such a long load length they wouldn't fit in a magazine while others you might have that issue.
So.. better safe than sorry. Regardless I think once you find out the best powder load you should play slightly with seating depth to obtain maximum accuracy. H110 / w296 likes the bullet touching the powder.
So according to Dellet to find the seating depth he'll take a fired cartridge (from your barrel) then fill it with "X" charge weight. Put hte bullet on top then measure the BTO - Base to ogive.
You got a hornady comparator or similar or are you going off of OAL measurement's only?
- I'd look into the Hornady Comparator or alternative's as this will get you a bit more consistency out of your loads. Ensuring the Ogive is the exact same distance from the lands on every bullet you load. VS loading by over all length - you may have some bullets closer or further away... only a couple thousandths but still a couple thousandths.
No comparator as of yet. So just for clarification, case length seems less critical when differences are marginal, but base to ogive is really where you want consistency across loads?
On seating to the charge level (Dellet’s method), what would take precedence, making sure bullet doesnt reach lands (nosler link I posted) or seating bullet right at/on the surface of the powder charge?
Think about that one for a minute.
Then understand that there are always exceptions to every rule of loading.
If you drop a charge, seat the bullet on the powder and it wont fit in the chamber, What is most important?
A lot off this stuff becomes cool jargon with no meaning, to hide a lack of knowledge. It does not matter how accurately you measure something if you have no idea of the reason you measure it. Base to ogive falls into that category, along with owning a comparator.
For precise shooting, consistency is king. Starting with how you wear your underwear, to how you hang your target. Change something your groups will change.
The purpose of measuring at the bullets ogive really has absolutely nothing to do with finding where it will hit the lands
I'll add a few more for emphasis
It's about getting the bullet seated the same length every time. If it was about touching the lands, you could measure it with one bullet and it would be the same for every other bullet of the same caliber ever made in that barrel.
Don't have a fancy tool?
guess what, if you have a caliper and reloading components, you have all you need. It just takes some thought.
Grab a case run it through the sizing die without the expander. Trim that case to and even .000 or .005 to make the math easier. That is just as accurate as any Hornady tool.
Grab 25 of any bullet out of the same box, measure and sort for overall length.
Now take the above case and use whatever length that is to "zero" your caliper. If it's digital it will do it for you, if it's dial learn to add and subtract.
Measure the sorted bullet groups by inverting the case over the tip, this will give you a bullet base to ogive length. This will show why this is the preferred method of measuring. I would not be surprised to see overall length vary .020" and base to ogive measure .002", depending on the quality or construction of bullet.
You can do the same with loaded rounds and find the exact same discrepancies.
The way jacketed bullets are made causes this problem. You can't draw the jacket over the lead core exactly the same every time. The lead and jacket variations compound so weight is inconsistent bullet to bullet. One way to correct that is to draw out the nose/tip. The base to ogive will be very consistent, but not the length.
Solids cut on a lathe do not really have this issue because of tighter manufacturing tolerances and methods.
Tipped bullets are somehwere in between
Next up is get rid of the notion that a comparator is a precision measuring tool. (that calls for a few more of these guys)
It is a Comparing tool that uses a measurement. It's a limit gauge that attaches a number, instead of pass/fail like a Sheridan Gauge. Instead of just knowing this is shorter than that, you can attach a number to it using a scale.
What a comparator does, is try to tell you where two cones of different angles/diameters will meet, by using a third diameter with a third angle.
Great for a repeatable point of reference, but far from a precise measurement.
Now after all of that, Why use a comparator?
Simply put, it makes things easier, maybe even safer.
Take the above bullets that vary .020". You happened to garb the shortest one in the box, found the lands with it and load the rest of the box .010" off the lands based on Cartridge Overall Length by adjusting your die to get the same length. A certain number will be .010" off and a certain number will be .010" in. Depending on powder used, that could be a 5-15,000 pound pressure spike.
The reason that happened, is that the seating stem does not seat on the tip. It's fourth cone of a fourth diameter and every bullet will be seated to the same depth, based on where those two new diameters touch.
A comparator and measuring off the ogive, is just a number and a buzz word, unless you understand why it's done and how it works.