Base to Ojive measuring

[OLD308]

I have a Innovative Technologies case and bullet measuring device. I also have all the Hornady accessories for dial calipers (Mitutoyo digital). So far I have performed the same operation using both systems on 3 different sessions (SMK bullets). Other than the outliners, the reading are all over the place each time. I know the actual reading can vary due to the measuring devise, but the grouping should be similar. No specific trend can be identified.

Just incase I'm loosing my mind I invited a buddy to use my tools and preform the same procedure. He preformed the procedure twice with each system. He stated boldly that I was failing to use the "soft touch" method that was the mark of a true reloader. He had the same experience. FYI he is a master class F Class shooter that swears by this bullet sorting method. So that sent him home to preform the same test. He did it twice with dial calipers and then I preformed the operation on his bullets with his equipment. He uses analog Mitutoyo dial calipers and the Hornady attachments. The results were closer but no where near what he thought they were. So thus far we have concluded that per our ability and equipment, sorting is not repeatable. Thus useless operation for us.

Question

Have I lost the ability to use any and all measuring devises? Is the use of the digital calipers messing this up? Any one bothered to run a "peer review" against their method or results? What method, tools, etc are you using that are repeatable?

Any help would be great. Honestly, I don't believe I can shoot the difference between the bullets separated or not. I call most all my misses so the bullet is not the issue. Just looking to advance my reloading skills. Thanks in advance.

 

[JOE62]

Are you saying you can’t get a repeatable measurement on the same bullets or different bullets from the same lot(or box)? I’m not familiar with the Innovative Technology tools so I can’t comment on that. You said your buddy tried measuring the bullets and couldn’t sort them either? Was or is it the bullets or the measuring in question? I just sorted about 400 Bergers and I found .003 difference from longest to shortest.

 

[65shootmoor]

I had a hell of a time when I first started sorting by ogive and every now and then it creeps back up. I end up making sure the comparator is clean (had a sliver of brass get jammed once), I use a digital caliper and write/zero it at the same point with the comparator, I also hold it to the light and make sure there is no gap (I've had it at the same zero measurement but it wasn't sitting flush with opposite caliper leg, skewed the results). I also hold the calipers vertical until the jaw clamps down and I give it a little wiggle to seat it properly if needed, but I don't ram the jaws home. I assume this is what your friend is referring to by soft touch. Only then will I lay it over horizontal, sometimes I just read it vertical. I've gotten different measurements on the same bullet in either position, vertical being the most consistent for me. That being said, I've sorted a lot of smk's and shot batches unsorted and have yet to see a huge difference. If the load can't hold a quarter inch group all the time, I wonder if the sorting even matters.

 

[spife7980]

Do the bullets measure consistently by themselves? Or is the inconsistency only in seating?

 

[OLD308]

Are you saying you can’t get a repeatable measurement on the same bullets or different bullets from the same lot(or box)? I’m not familiar with the Innovative Technology tools so I can’t comment on that. You said your buddy tried measuring the bullets and couldn’t sort them either? Was or is it the bullets or the measuring in question? I just sorted about 400 Bergers and I found .003 difference from longest to shortest.

Digital calipers, analog calipers, and the IT gauge are not providing repeatable results measuring base to ojive. Same bullets measured with my measuring devises. Same bullets used with my buddies devise.

No, he did sort his bullets the way he always had. When he double checked them the groupings did not match.

The question is has anyone bothered to recheck their measurements. Then compare them to the measurement of another person preforming the task. Creating a layman's peer review.
Again, I understand the exact measurement may change due to other variables. but the groups produced from the measured bullets should be similar.

Example, sort your 400 bergers again and see if the groups divided into .001, .002, .003 have the same number in each group as they did before.

 

[OLD308]

Do the bullets measure consistently by themselves? Or is the inconsistency only in seating?

Measuring the bullets by them selves.

 

[65shootmoor]

Each of the tools would, potentially, have a different measurement from each other. I've got 3 calipers that all read it differently. If the same caliper starts varying, it's something I'm doing that is not consistent. Are you having different measurements with the same tool, and if so, how many projectiles have you sorted total in all of your reloading experience?

 

[spife7980]

Measuring the bullets by them selves.

What about when they are seated? I bet the seater die sets the cbto pretty accurately if you have a good control on your neck tension.

 

[OLD308]

For give me for not articulating the issue correctly. I'm sorry I don't know how to explain the issue clearer.

Example
Measuring devise A produced a variation in the 500 SMKs of .005. The groupings broke down as follows
.000, 100ct
.001, 200ct
.002, 50ct
.003, 50ct
.004, 25ct
.005, 75ct

Measuring devise A used a second time by me produced a variation in the 500 SMKs of .004. The groupings broke down as follows.
.000, 200ct
.001, 100ct
.002, 50ct
.003, 50ct
.004, 100ct

Measuring devise A used by my buddy on the same SMK bullets. Produced a variation of .003. The groupings broke down as follows.
.000, 200ct
.001, 100ct
.002, 50ct
.003, 150ct

Regardless of the measuring devise used, or the operator, the groupings were not similar. So my question is as follows. Have you ever bothered to check your sorted bullets again to see if your measurements are repeatable. If so, what method did you use. I'm open to the possibility that I'm failing is some way. But, as my buddy has confirmed, my theory is that this measurement is not repeatable.

 

[OLD308]

What about when they are seated? I bet the seater die sets the cbto pretty accurately if you have a good control on your neck tension.

Haven't gotten around to seating the bullets yet as the sorting of the bullets is not complete. I have Custom Whidden custom dies for this rifle and bullet.

 

[65shootmoor]

For give me for not articulating the issue correctly. I'm sorry I don't know how to explain the issue clearer.

Example
Measuring devise A produced a variation in the 500 SMKs of .005. The groupings broke down as follows
.000, 100ct
.001, 200ct
.002, 50ct
.003, 50ct
.004, 25ct
.005, 75ct

Measuring devise A used a second time by me produced a variation in the 500 SMKs of .004. The groupings broke down as follows.
.000, 200ct
.001, 100ct
.002, 50ct
.003, 50ct
.004, 100ct

Measuring devise A used by my buddy on the same SMK bullets. Produced a variation of .003. The groupings broke down as follows.
.000, 200ct
.001, 100ct
.002, 50ct
.003, 150ct

Regardless of the measuring devise used, or the operator, the groupings were not similar. So my question is as follows. Have you ever bothered to check your sorted bullets again to see if your measurements are repeatable. If so, what method did you use. I'm open to the possibility that I'm failing is some way. But, as my buddy has confirmed, my theory is that this measurement is not repeatable.

Per your example, I'm betting your buddy has more experience at this than you. Your samples improved after what is essentially practice. The number of samples isn't really relevant because you are in fact sorting to discover variance. The difference in number of samples between you and your buddy is the difference in experience, his results are probably the more accurate sort. Only question I have is what are you meaning when you stated above "the groupings were not similar."? Are you referring to the spread (the actual range of different numbers) or the numbers themselves (meaning his numbers vary 0.003" around 0.727" and yours vary 0.005" around 0.734")?

 

[65shootmoor]

Also, I've actually never had a box of SMK's vary more than your buddy's readings. It's why I chose to shoot them over others. I've even had them tighter than that and have measure thousands from several different lots. The actual ogive length box to box might change a tad, but within that measurement, they always averaged 0.003" or better. It's got to be your technique or Sierra has slipped a lot.

 

[Deleted member 10043]

Stop over measuring shit. You're going to go crazy.

 

[OLD308]

The example I wrote out was just an example. I'm on the road and don't have access to my book for the exact measurements. I'll stop this thread now as I have failed to explain in a manor that can be understood. I don't know how to make this any clearer. I thank all who attempted to help me. Sorry for the not clarifying the issue.

 

[spife7980]

We get your sort results changed between the first round and the second time back through. We can’t tell you why your thing did what being speculating at information we don’t have.

My question now is, are your measurements on the same bullet repeatable? If they aren’t then you are then you are the variable. And by your results... your measurements aren’t repeatable.

I still bet when you seat them they all locate correctly.

Get an anvil base for the hornady, it makes it easy and you can spin with a light touch to locate the center. Make sure both comparator pieces are square with one another.

 

[pmclaine]

I took a measurement of length base to lands on a rifle this week.

I used a Hornady case drilled and tapped for the Hornady tool to "push" the bullet from the case into the lands.

The bullet was a 175 SMK.

I took 10 measurements than just used the average of the 10 measurements.

I feel the same as you do OP.

I use the average of what I do right and do wrong in hopes I end up with a useful number.

In my experience none of this shit works the way it is supposed to.

I use a Redding micrometer seater insert in my Redding seat die.

It's calibrated so each "tic" mark moves the seat depth .001.

Do you think I have ever had a bullet move as the tool states it's designed?

Just do your best and go with it.

 

[Sutherlandsd]

The Hornady case and tool to measure oal is never going to be accurate. Most often is been my experience that when a user has what they think it's oal it's usually about .020 into the lands. The wheeler method is repeatable and much more precise.

Honestly if my gun likes the bullets .020 off I don't even separate mine anymore.

 

[Steel head]

Stop over measuring shit. You're going to go crazy.

This!

Measuring bullets????

 

[spife7980]

I posted this in my dasher 115 rdf thread but I took a sample of 10 and measured them along the way and these were the results

Bullet #	Bullet Over All Length	Bullet Base To Ogive	Cartridge Over All Length	Cartridge Base to Ogive	Weight
1	1.349	0.77	2.368	1.7915	115.12
2	1.346	0.77	2.367	1.792	115.06
3	1.347	0.77	2.365	1.7915	115.16
4	1.351	0.7695	2.37	1.791	115
5	1.349	0.77	2.369	1.791	115.04
6	1.341	0.7705	2.36	1.791	115
7	1.345	0.77	2.36	1.792	115.14
8	1.347	0.7695	2.368	1.791	115.08
9	1.349	0.7695	2.368	1.791	114.96
10	1.346	0.78	2.356	1.791	115.2
Average	1.347	0.7709	2.3651	1.7913	115.076
Max	1.351	0.78	2.37	1.792	115.2
Min	1.341	0.7695	2.356	1.791	114.96
ES	0.01	0.0105	0.014	0.001	0.24
SD	0.00265	0.00305	0.00450	0.00040	0.07419

I say to not worry about the smaller variations as they should all seat to the same place.

 

[MarinePMI]

Did you look at the base of the bullets (visually)? A lot of times, the base of the bullets vary...a lot. My suspicion is the tooling running at speed and wearing out, or sticking slightly in the machines.

A lot of bullets I see, the boat tail length varies or the base may have a divot or slightly concave surface. Since these are typically swaged lead core bullets, the material has to go somewhere. Sometimes the ogive shifts forward/backwards, sometimes the jacket itself stretches. I was pulling my hair out one day, until I noticed the differences in the base of the bullets in a single box. Sure enough, the indentations of the bases and slightly different length of boatails matched what I was seeing (delta wise) when using a comparator.

A lot of bullets aren't as uniform as many think...

 

[Greasegun]

Calipers are good to +-.001 and I dont care if you own mitutoyo starrett or import junk, dont trust them any closer than that. I have been a machinist for 20 years. We dont measure precision parts with calipers. That said, split your batches up into bigger lots so that your measurement error is smaller than your lot spread. Example, group everything from .000-.003 together and everything from .004-.006 together. Then youll have reasonable confidence they are at least in the right group. I would have a hard time believing a .001" difference would matter in any measurable way anyways. Another idea is, if say 80% fall within .001-.003 range, keep all those in one batch and put the other 20% outliers in a fouler/sighter pile.

 

[Precision Underground]

Take your calipers and open them to .005 and look at the size of it. Then tell me that is going to make any difference on the target when you ram them 65000ish psi out of a barrel. Stop and spend the time you are using here on dry firing and working on technique. Your targets will be better and you will be much more sane!

 

[riverside jeep]

Awhile back I started bitching about my c.b.t.o. measurements varying up to .010-.020 using sierra match king hollow points and also with the tipped match kings. I grabbed a box of bullets and started measuring and found them to be very consistent at the bullet base to ogive but a lot of variation at the ogive to tip (meplat) which of course is where the seating stem contacts the bullet. In my load development I have found that +- .020 window of jump distance for optimum group size so that much variation is not going to cut the mustard. I am using run of the mill RCBS dies so I reached out to the RCBS tech line and he had me send in 3 bullet samples of each bullet and they custom made seating plugs for both. I received them today and stuck a bullet into the seating plug and it didn't get any closer to the ogive than the standard plug did but I give it a try anyway. After I set the depth they have all been within .001! SUCCESS! Thank you RCBS.

 

[427Cobra]

less time reloading means more time shooting, what will actually make you a better shooter

 

[spife7980]

More time reloading means more time shooting, what actually makes a gun shoot better.

 

[Dthomas3523]

less time reloading means more time shooting, what will actually make you a better shooter

If the ammo is only capable of .75 and has a high ES.....the best shooter in the world can only shoot .75 and might miss at distance on a high or low ES shot. Can practice all you want, it won’t matter.

It goes hand in hand.

 

[Precision Underground]

Awhile back I started bitching about my c.b.t.o. measurements varying up to .010-.020 using sierra match king hollow points and also with the tipped match kings. I grabbed a box of bullets and started measuring and found them to be very consistent at the bullet base to ogive but a lot of variation at the ogive to tip (meplat) which of course is where the seating stem contacts the bullet. In my load development I have found that +- .020 window of jump distance for optimum group size so that much variation is not going to cut the mustard. I am using run of the mill RCBS dies so I reached out to the RCBS tech line and he had me send in 3 bullet samples of each bullet and they custom made seating plugs for both. I received them today and stuck a bullet into the seating plug and it didn't get any closer to the ogive than the standard plug did but I give it a try anyway. After I set the depth they have all been within .001! SUCCESS! Thank you RCBS.

Yea if you are seating off he tip you will have issues for sure.

 

[427Cobra]

I have ammo that consistently shoots sub .5moa, I don’t sort bullets by ojive length, or weight, and I don’t have the time to do so, a precise powder charge, annealed brass, and bullets seated by ojive not OAL are very important, as is a repeatable process that replicates a consistent result.

 

[Walker TR]

Unless you are shooting F-Class and trying to get your masters...."Stop the insanity" load them and shoot them, it is not going to make that big of a difference at all.

 

[riverside jeep]

Yea if you are seating off he tip you will have issues for sure.

Yes, I believe we all set off the tip of our bullets but what it comes down to is that the run of the mill seating plugs must work with a very wide variety of bullet profiles. The std plug ends up only making contact one only 1 area of your bullet (hence the little ring that appears on the bullet after seating) Verses a custom plug that is profiled for 1 particular bullet and make full contact, thus spanning the imperfections that cause the erratic seating depth. Merry Christmas to all.
p.s. Epstein didn't hang himself

 

[LR51]

Interesting concept