bullet length ?

[LoneRider]

i understand that its not a good thing to have the projectile against the lands,but how far off is good or bad ?
i split the side of a case and popped a pill in then measured it.
4 different projectiles,4 different bullet lengths.?
whats right ?

projectile seated in case,bolt closed.
178gr A-max - 2.873,5"
168gr A-max - 2.890.5"
168gr speer hpbt - 2.868.5"
155gr nosler hpbt - 2.866.5"

unless ive done it wrong,so i will wait a day or two before continuing.

sean. [apprentice reloader]

[trevort]

You need a measurement from the ogive. A competitor tool. And target loads in the lands are pretty common place especially with long pills. Just work up as per normal

[Bidgee]

If you are using a calliper to measure from base to tip you are going to have trouble as the tips of bullets are inconsistent. You need to measure the ogive which is about where the bullet will contact the lands.



Because different bullets have different ogives you'll get different lengths. I usually aim to seat the bullet .02-.04 off the lands.

The split case neck technique works and I've used a lot but make sure you measure it 5-6 time to get a reliable measurement. Sometimes the lands grabs the bullet and will pull it back out of the case a bit as you extract.

Often with those longer bullets like the 178 AMAX they wont fit in the mag when seated close to the lands so I seat them to fit the mag. In my remmy .308 that's about 2.825" (tip to base).

A better option is the Hornady comparator. Google it and you'll see how it works.

Happy reloading.

[LoneRider]

thanks guys,this ammo is for the omark TR.
i have the digital verniers and measured base to tip.
i seem to remember when i did this for 303 i put ink on the proji to see if there was any movement on extraction.
i'll do it a few more times with each,just to make sure.

sean.

[trevort]

But as we both said, tip to base is irrelevant. You need to measure from the ogive

[LoneRider]

but arent you going to get that by the split case measurement ? they way i am doing it ?
its the seating depth i am trying to figure out.....

by closing the bolt on a case and pill and subtracting a bees dick from the overall length arent i going to get the measure i am after ?

[Tackleberry]

but arent you going to get that by the split case measurement ? they way i am doing it ?
its the seating depth i am trying to figure out.....

by closing the bolt on a case and pill and subtracting a bees dick from the overall length arent i going to get the measure i am after ?

now if you don't have a bullet comparator how can you measure the OTB accurately

this

IMG_1906.JPG (89.33 KiB) Viewed 1373 times

as opposed this .

IMG_1907.JPG (94.8 KiB) Viewed 1373 times

if you measure like this your ogive will be up to 0.010" or more off the spot
as the overall length of the nose of the bullets are very rarely the same even from match grade pills.

[Waldo]

I have what could be considered by others as a bit of a rough method, assuming magazine length isn't an issue I'll use the split case method. Measure to the tip with the verniers, run a few tests to make sure I'm getting basically the same measurement then set my loads 20 thou shorter. Have been known to go a bit further on occasion because it didn't quite look "right"

Working on the theory that the 20 thou at least will give me some scope to ensure I'm not jamming one into the lands if the tip of the one I've tested happens to have a different complete length to his box mates.

It may be a bit rough but before I started measuring I found out when I did check that the .222Rem was running nearly 90thou off the lands (using Nosler data) and still shooting pretty damn nice

A bit rugged but seems to work for me.

Cheers,
Waldo

[Rinso]

but arent you going to get that by the split case measurement ? they way i am doing it ?
its the seating depth i am trying to figure out.....

by closing the bolt on a case and pill and subtracting a bees dick from the overall length arent i going to get the measure i am after ?

No you cannot obtain an ogive to base measurement this way, at least not an accurate one.
You are correct as far as obtaining a seating depth ie seat bullet using a split case and chambering it then use the resulting dummy round to set up a seating die. Remember that the bullet will most likely be jammed into the lands so seating die needs to be wound down from this point.
You can use marker or smoking techniques to find the land marks and adjust from that.
This will only give you a starting point for load development.
You cannot measure the loaded round and use that figure as a base line as the overall length will vary with every bullet making that measurement useless. The ogive to base method gives a repeatable reading as this mimics the seating die & chamber in so far as the contact point with the bullet are concerned.
You can purchase a number of different types of comparator for this purpose or if you have access to a lathe you could machine one up.

[LoneRider]

thanks waldo,that is helpfull.
thanks rinso.

i dont have a comparator,

ok,just looked one up.sinclairs looks the easiest [opposed to hornadys]
how long would it take to get one from the states and/or can i get one here ?

[Brad Y]

Lonerider

Get the hornady comparitor set with all the different inserts for different cals. Easier to find in Aus.

I recently shot two different batches of 6mm berger hybrids. You wouldnt believe the inconsistencies not only between batches but also within the second batch. Im talking bearing surface length, weight, base to ogive length, overall length and weight. There was also a fair difference in diameter of the two batches. Now shooting JLK VLD's and had no more than 0.2gr weight difference in a box of 200 and base to ogive length was no more than 3 thou. I put the sorted piles back into one box, meplat trimmed and pointed them all ready for this years 1000ydBR season.

As for how far to seat a bullet from the rifling? Only your gun will tell you that with proper load tuning.

[Ned Kelly]

G'day all,
the best way to accurately set up dies is ogive to base measuring with a comparator such as Sinclair's or Hornady's.

But you can also use just ONE projectile only to get good repeat measurements of touching the rifling using case base to bullet tip will give exactly the same deal. It doesn't matter whether you are measuring from case base to ogive or bullet tip......YOU MUST ONLY USE THAT BULLET, no other bullet. You can't swap bullets in a pack as they will vary in overall length and thus change your measurement's.

This process will work just as well, but without the convenience of a bullet ogive comparator.

Once you have a good repeatable measurement you can now set your seater die up BUT using the SAME bullet to seat the SAME bullet to the SAME overall length (case base to bullet tip) and then reduce seated depth by 10, 15, 20, 25, 30 thou etc. This will work fine for all the other bullets in the box and you will have set you seater up as well as any Competition shooter could.

I'd also check that seating depth again after say 200-300 rounds to maintain the same distance from the rifling as the barrel/throat wears to ensure optimum accuracy.

Also if you change you bullet choice, even if they weigh the same, you will need to re do this setting and adjust your dies as the ogive WILL be different even if the bullet is from the same maker.

I'd make sure you were a minimum of 10 thou shorter to ensure you had a bullet jump to avoid stuck bullets in a hunting rifle but I have found that most projectiles do shoot amazingly well when jammed into the rifling, i.e. +10 thou longer.

The only thing I would do is find a bullet with a relatively flat tip or a very light touch up with some fine sand paper or borrow wifey's nail file for a consistent surface to measure from of course!

Hope this helps

Cheerio Ned

[LoneRider]

thanks Ned,that was my original train of thought.
but then i went and bought a sinclair comparator,what a pain in the ass trying to set the seating die.
12 rounds,12 different sizes and 2 wouldnt even chamber.

i worked on this problem for about 2 1/2 hrs this morning.
theres 2 things i can think of as the culprit.fat case or long case.
the cases were used in the clubs omark,and not thinking i started reloading those cases.

the dummy round i made to get the bullet length doesnt match the finished bullet.
that gave me no end of grief,i couldnt full length size the cases because they were ready primed.
in the end i changed cases from the winni i was reloading to unfired factory fed's.
pulled all the pills kept the 2208 and chucked the fed powder.

the only thing i am sure of at this moment is the cases all have 45gn of 2208.
every time i think i got it right,i chamber a batch and find im wrong.
its got me stuffed.

when i can, i will buy new cases,hopefully before i run out of powder.

bugga ay...

[aaronraad]

that gave me no end of grief,i couldnt full length size the cases because they were ready primed.

Depending on your FL die type, you can back off the decapping/depriming pin by screwing it back out and locking off, or remove the decapping pin itself from the expander button and go at them. Either way you shouldn't go anywhere near the live primer. I've done this without incident given my limited experience but I'd recommend getting advice from a few sources on the process before attempting something similar first.

the only thing i am sure of at this moment is the cases all have 45gn of 2208.
every time i think i got it right,i chamber a batch and find im wrong.
its got me stuffed.
bugga ay...

Here are a few tips before you start dumping brass.

Essentially cases from the same batch should resize relatively consistently, if they are all in the same state and undergone the same processes, i.e. all new factory brass or all once/twice/thrice fired brass from the same chamber etc.

First off you want to confirm if your reloading press is suitable for full-length resizing because not all are, or at least not all that flash at handling anything but small pistol cases...maybe. Example is the Super Simplex 5/8" indexable turret press (typically 6-hole). I borrowed a couple of stations for neck sizing and seating on my father's SS when I got started in reloading 308W for fullbore. I just used a 308W Simplex vice type die for full-length resizing every now and again. Bought a Hornady 007 O-frame press with the quick-lock bushes and Redding dies eventually.

Next issue I would look at is lubrication for the case for full-length resizing. It's about consistency. I only apply the sizing lubricant to the outside of the case body by rolling on a pad. I only apply enough to avoid build up in the die and dented cases. The necks should be relatively clean and I just dip them in graphite powder to reduce the drag on the expander mandrel. Removing the lubricant from the cases is important, so is giving your dies a clean every now and again just in case the lubricant builds up too much or you've accidentally dragged something foreign in there that might impact significantly on your loads.

A quick check of your shell holder just to make sure it's holding the cases firmly and consistently. Compare a few pieces of your brass as well to make sure the extraction rims are consistent and not being deformed by some action of your firearm during loading, firing and unloading including feeding from the magazine if that is the case. Shell holders and brass extraction rims can vary significantly across brands. Double checking you are using the correct shell holder for the cartridge, as recommended by the manufacturer, doesn't hurt either. You might start to accumulate a few, or one is included with a 2nd-hand set of dies, as shell holders are not always supplied with the dies by manufacturers. Dies might also have to be adjusted to suit a brand or batch of brass depending on the inherent spring-back properties of that particular brass. Not all brass has their neck/shoulders annealed to same state, nor their case heads hardened to the same level.

Assuming you're dies are locked down adequately in your press you probably have the most likely culprit, the bullet seating stem...I'm pretty sure Waldo went down this path most recently. Not all current standard factory supplied bullet seating stems are compatible with some of the more modern long ogive projectiles, designed to optimise ballistic coefficient properties. Basically the adjustable insert in the bullet seating die is ground with a cavity that doesn't match the projectile's ogive by being too short or too acute an angle. Invariably once the projectile is seated off the meplat instead of further back along the ogive you get variable seating depths. Open tip designed projectiles tend to vary in length given the limits of jacket tolerances and sometimes this is delivered in the form of the ogive length and therefore the meplat shape and/or diameter. This goes back to your original post in terms of the preferred method of measure cartridges for seating depth. Sometimes you can see deformation taking place on the meplat itself if your neck tension is high enough, but not always. Plastic tipped projectiles (e.g. Amax) are very good at hiding the issue as you can imagine. If the seating stem is the issue, you can change back to a short ogive type projectile, modify the stem (by removing or adding material), or source a suitable stem for your die. Redding make a seating stem specifically for VLD projectiles and there are probably a few others if you look around.

Did we mention that you might have to chase the seating depth every 300-700 rounds, depending on wear rate of your barrel's throat region??? We often point out that 'over-bored' cartridge designs have higher wear rates, but this still comes down to how hard you load them. The other factor we sometimes overlook is the basic quality of the barrel steel and it's finished properties. Some steels are softer than others for machining purposes and some stand up to thermal abrasion and erosion better than others. It's amazing to think a custom target grade barrel (before chambering & fitting) will cost you 10x the value of the barrel on a cheap factory rifle these days, actually for money you can buy nearly 1 & a 1/2 complete cheap factory rifles.