Measuring OGIVE

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ninosdemente

New member
I have been going to youtube/google to see/read on measuring ogive as this is something that I did not do on a previous load. Was helped on a different thread when I had problems for .223.

I did see different tools. Are there must have tools for this or is there another way to measure without obtaining the tools or some of the tools?

At the moment loading for .223/30-06. Looking to load .380/9mm/5.56 which I only have dies for the .380 so far.
 
Ben Dover said it all . If you were loading for one caliber I would recommend the RCBS Precision Mic , in your case the comparator is the way to go . Finding the ogive measurement , what I found is on a bolt action using a stripped bolt if possible , seat a bullet in a sized unprimed of course with no powder , seat it long , it won't chamber , lower the bullet very slightly each time until it chambers with no resistance , use a marker on the bullet to see if any rifling marks are still showing . You want to find that zero measurement , from there you can either test what works best in your rifle jump or jamming your bullets . With your pistol reloads use listed OAL for the bullet your using with the powder . Hope I Helped .
PS
Once you have that rifle sample sized bullet you use it in the comparator to get the ogive measurement , keep that sample round for checking your reloads . You can make a few like that and mix them in with your live rounds to test yourself for a flinching . See what happens when you press the trigger on a dead round . You may be surprised how much you move , a great training method . Reloading isn't so complicated but you do have to have the tools to do so . Hornady Comparators are all you need . Your doing all the right things and asking the right questions . Again on your handgun rounds just follow the book measurements and you'll be fine . Hand gun reloading is easier then rifle , roll crimp on revolvers taper on autos.
 
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The best tool for the job is when you make the rifle and cut the barrel, take the drop from the blank and chamber it with the same reamer you used to chamber the barrel.

Now you have the perfect case gauge, as it is an exact copy of what your barrel is.

Other than that a marker and some time can do the same thing.
 
nino
Is this needed, no. The tool is to sloppy , I bought one , the idea is good but isn't accurate . Most of us can't get a piece of a cut off rifle barrel to use as a comparator . The Hornady Comparators is the easiest way to measure . Look on line at the videos , the problem with the lock n load tool is when you have the case in place an you extend the shaft with the bullet to hit the rifling , he bullet will stick giving you different readings .I found making a dummy round and using your chamber the best and most accurate , takes alittle time going from the die to the rifle but it gets you there . You will try different things , videos are helpful . I have plenty of tools I ordered found them OK but not good .
 
In the strictest sense, the ogive of a bullet is simply the arched surface between the flat portion and the tip. Practically, in reloading, the word is used when attempting to determine the bullet seating depth (or overall cartridge length) where a particular bullet just touches the rifling of a specific chamber/barrel.

There are all sorts of tools that are intended to make it easy to determine the seating depth/OAL. In those cases where an exact measurement is needed, the tools are likely necessary. But I submit that in many cases, no tools beyond a set of calipers are required to determine the seating depth/OAL within about .005”. By “many cases” I mean the many occasions where the bullet length itself can vary .005” or more, and where the target seating depth/OAL places the bullet more than .010” from the rifling.

There are at least a few methods for determining seating depth/OAL using only calipers, an empty case fired in the rifle, and the desired bullet, and perhaps a cleaning rod. Those methods have been described on a number of occasions on this forum.

I'm not trying to discourage anyone from buying tools. Buy them if you like. I'm just saying that the tools aren't a requirement in many cases.
 
I did see different tools.
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Again: A man built 4 magnificent rifles; he does not know what happened but one of the rifles had a problem. There was nothing suspect about him or the smiths that could not help him but one day he found his way over here.

He wanted to know where would I start when trouble shooting the rifle. I informed him I would start by determining the length of the chamber from the bolt face to the lands. I was not concerned with the length of the chamber from the shoulder to the bolt face because he had 200 fired wildcat cases.

He hoovered over the computer looking for methods and techniques for ways of measuring the distance from the lands to the bolt face. Final he came up with what I would call a contraption.

Anyhow: I took a few of his formed cases and drilled the primer pocket/flash holes out to the diameter of a cleaning rod, I then neck sized his cases to increase bullet hold ( I am the fan of al the bullet hold I can get). Once I secured the biggest, heaves and longest 7mm bullets I had in the case neck I removed the bolt,chambered one of the test cases and then inserted the cleaning rod in the drilled out case head.

And then I started pushing the bullet out of the case, the bullet came out of the case neck and traveled and traveled and finally hit the rifling,

It was about that time I explained his problem to him; too much free bore. He wanted to know how much free bore, I explained to him it did not matter, the problem could not be fixed with a 7MM shooting Time Western or anything H&H or Weatherby. He knew he would have to start over with lengthening the magazine or moving the barrel back etc.. He wanted to know how something like that could happen. I suggested someone decided they could increase the length of the throat to get more powder or they wanted to give the bullet a running start. Giving the bullet the running start decreases pressure.

So? The tool I use to transfer the dimensions from the chamber to the seating die is the same tool I use to determine free bore. I drill out the flashhole/primer pocket, I size the neck for good bullet hold. I seat a bullet, remove the bolt and slide the transfer into the chamber. After that I start pushing.

Pushing the bullet out of the case neck is a rare occurrence. Normally the bullet stays in the case neck and stops at the rifling. Once the bullet contact the lands there is nothing to be gained by showing off. A reloader that can measure the distance from a datum to the case head can measure the distance from the ojive to the case head. The difference is some reloaders believe using ojive instead if datum makes them sound cool.

Me? I always want to start out by knowing the two diameters of the barrel.

F. Guffey
 
BBarn
That's true but who wants to go through the hole process every time . To make life easier using a dial caliper for handgun cases for AOL in a auto for proper length in magazine feed and length for cylinder . Rifle is more precise if your looking for accuracy if not then go with book listings in OAL and only need a caliper . Ogive is more exact will require a measuring tool or your rod method.
 
BBarn
That's true but who wants to go through the hole process every time
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There are reloaders that have to start over everyday. And then there are those that have following instructions. When I go through the 'trouble?' of determining the distance from the lands to the bolt face I save the transfer. That is the reason I do not make dummies; a dummy should know what it is worth.

And I ask why is it necessary for a reloader to find the rifling over and over and over again? And then there is the next day; if the reloader had a good understanding of threads and had measured the distance from the top of the die to the press last month he should be able to go back to that measurement simply by measuring the height of the die above the press with a height gage.

F. Guffey
 
Me? I always want to start out by knowing the two diameters of the barrel.
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why?

And I ask why is it necessary for a reloader to find the rifling over and over and over again?
Click to expand...

you never heard of throat erosion? It's not a everyday occasion but I have had throats erode .040 over the course of their lifetime
 
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you never heard of throat erosion? It's not a everyday occasion but I have had throats erode .040 over the course of their lifetime
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You are not going to start over everyday and if you have determined the length of the chamber from the beginning of the rifling to the bolt face and if you saved the transfer it should not take you long to determine how much the throat has eroded.

F. Guffey
 
Guys were trying to help someone new to reloading , as time goes on I'm sure as he gets deaper into reloading , log books , case prep , different powders and bullets to try . The basic questions he's asking for help , One thing that did confuse me what F Guffey said " using ogive instead of datum makes them sound cool " now to me that's confusing . I use datum and ogive , I'm not trying to sound cool but aren't they two different things? Sorry nino for adding to the confusion.

Chris
 
No problem cw308. Lol.

Heck.. I'm glad the thread is getting some posts. It is difficult to always get an agreement on anything specially as many people have different techniques/tools that help them which can/won't help the next person. I like to hear them out still... although the majority of the time some information is confusing to me as some posts here.

I don't want to say I'm gullible/naive, but as completely new to this I somewhat try to follow the advice/procedures/tips and see if that is suitable to me if it pertains to me. Of course, it's a bit difficult to buy recommended tools as I would have a variety of tools as people always recommending different tools that have help them. As lacking experience, I do tend to try "find" the easiest/faster solution in a good sense. Maybe not the best route as I am still starting out reloading. For example, when I first started buying items for reloading, I purchased a universal decapping die. My thinking was, if I don't have the dies yet, I can at least remove primers from brass from the range. I did use it but then I notice it was just money badly spent as it only prolonged the process as I would still have to resize. Maybe I should start a thread of tools/items people bought and now have no use for them. Maybe I might be able to buy some used tools, lol.

I have only loaded twice. One for 30-06 and .223. Unfortunately the .223 has been giving me problems specially with the Hornady VMAX. The projectile was receiving marks when trying to chamber. Which is why I started the thread. Eventually I used the Nosler CC for the Savage 12FV, still minor marks but to me acceptable compared to the VMax. In a way, I refuse to not use the VMAX. Perhaps I should and stick to something different such as the Nosler.
 
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Ninsd:

I use the Hornady tool. I have the calipers and it does fine. Low cost, works fine, lasted 5 years now.

Just to make it interesting, my setup, rather than get the separate adaptors for the minimum shoulder bump back (also known as minimum resizing) I just drilled the 22 caliber bullet one out to the case size of 308/06 to hit on the shoulder.

I can't compare to anyone else as its "unique" - but I don't care, it tells me what I need to know (have I bumped her back to my desired bump back or not?)

A lot of this is not a right or wrong but simply how you want to do it. I have fun making my own small tools so I did. The adapters are cheap.

You can simply keep bumping the bullet back .010 until the marks stop. I have the 12FV and in 308 the bullets tend to stick (more pointy ones). I just tap the handle back gently with a plastic handled tool.

I have had cases (pun) where I have been merrily using one Ogive and one sticks. Its just an odd out of spec bullet. I tend to move back a bit just to give it latitude, I am not going to ever reach bench rest status so if it shoots under 1/2 inch MOA I am happy.

And yes everyone will tell you what their favorite tool is, best is if they describe how they use it and it resonates.

We all have a few of those around, unfortunately it takes experience in both the new world of reloading (9in this case) as well as how you work best.

I could no more live in Mr. Guffys world than he could in mine. Kind of like anti matter. Granted I think mine is more mainstream, his may be more technically right.

But as they said in school, get boys on one side and girls on the other side and keep moving half the distant toward each other and they will never meet.
On the other hand in not too long a time you can kiss the girl (if she is willing of course, sigh, no one ever wanted to be opposite me)
 
ninosdemente
The universal decapper is a good tool to have , I wet tumble , using the decapper first the primer pockets come out spotless along with the cases inside and out . Makes sizing a pleasure . You are doing all the right things , asking questions , watching videos and reading . You'll do fine .

Chris
 
There are lots of tools and comparators to measure the bullet ogive. If you are consistent with them, all should work.

Just don't grab one brand and expect the measurements to transfer to another brand. Most times, it ain't gonna work.

After you determine the bolt face to lands measurement, measuring your handloads for consistent bullet jump is a breeze.
 
As a example let's say your ogive measurement is 2.150 as a zero and want a .005 jump your ogive will be the same 2.145 no matter what bullet your shooting but some brands may shoot well and some may not. They will all chamber the same as long as it's 2.145 if measuring OAL on different types of bullets you will have different OAL measurements.
 
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