Hornady LocknLoad OAL gauge inconsistencies??? Solutions?

Tikka223

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I just got a Hornady OAL gauge for my T3 CTR in 6.5 Creedmoor. I’m loading 140gr ELDM bullets. I have the modified case for Hornady and the .26 insert for the bearing surface on the ogive.

I’ve watched a few videos on how to use it and it’s seems really straight forward. My process is as follows:

1) Make sure everything is screwed together firmly
2) Insert the modified case into the chamber quickly enough that I hear it tap the end of the chamber
3) Hold it firmly in place while I push the bullet to the lands
4) Gently tap the rod that pushes the bullet into the lands a few times
5) Measure

My results are much less consistent then I had hoped:

2.274, 2.216, 2.185, 2.222, 2.195, 2.179, 2.207, 2.205, 2.198, 2.209


I wondered if my step 4 could be having an effect but I found that just pushing the bullet into place felt mushy and inconsistent. When I inspect the bullets I see that they have contacted the lands. Am I being too rough and thus causing inconsistency?

Anyone have some suggestions on how to improve the consistency? Could it be that these bullets aren’t consistent in size?
 
I just tried pushing the bullets firmly and still got pretty loose results:

2.245, 2.279, 2.222, 2.107, 2.206, 2.274, 2.246, 2.215, 2.276, 2.270

If I want to be .02 off the lands i have no idea what to load for. This is a bit frustrating.
 
I have a copy of the Hornady tool, I use it in a .243 Win Tikka T3.
My results are very consistent, within .002" over 5 tests using the same bullet each time.
It sounds like you used 10 different bullets out of the same box?
Have you tried repeating the test 10 times with the same bullet? That will eliminate inconsistency from one bullet to another. If you still get widely varying results it's your technique that's causing the problems.
If it is technique, be sure you are holding the modified case firmly in contact with the shoulder of the chamber as you push the bullet in and lock the center rod.

I never tap , I just hold firm pressure on both the outer sleeve and the center rod as I gently tighten the locking screw against the center rod. If either moves, you'll get inconsistent results.
There might be a slight variance from bullet to bullet, but nothing like what you've described.
 
Different bullet each time. I figured if I wanted .02 off the lands it would have to apply to each bullet anyways. Maybe there really isn’t much point if there is that much variability within a box of bullets.
 
I don't think there is that much difference, which is why I suggested you try several times using the same bullet. You should definitely be able to be consistent within .003"-.005" using the same bullet. I think there's something else wrong.
 
I reload a Remington 700 in 243. I find if I place the gun, barrel down and let the bullet “fall” in the chamber/barrel. Then I put the cartridge case “into the bullet base”. Then I slide the grey rod until I have contact with the bullet base. The bullet always stays in the barrel, so I use a wood dowel to push it back out., then put it in the case for measuring. I always measure base to ogive.
I am able to get multiple measurements within a few thousands of an inch. I usually measure about 8 times.
 
I am able to get multiple measurements within a few thousands of an inch. I usually measure about 8 times.

Same here, although I only do 5 measurements, then take the average. I'll do that with 3 random bullets out of the same box, and again average the 3 measurements.
I usually seat bullets to be .015"-.020" off the lands, so a few thou variance isn't a big deal anyway.
 
The tool could have been better if the rod was made of metal (any metal) instead of plastic.
I am certain that mine will eventually wear out because the plastic.

That issue aside, I take five separate readings using the same projectile using generally the the same steps as you.
The extreme spreads in readings (CBTO method) over the measurements is typically around 0.005 maximum.

However, the first time I ever used the tool was in a 223 with a absolutely filthy chamber and throat.
I was getting highly variable readings in CBOT and I believe that its was a result of debris.

I am curious.... are you measuring the Cartridge Base To Ogive (i. e. with a comparator on the end of your calipers) or are you just measuring to the tip of the projectile after using the guage?

If you are measuring at the tip of the bullet (i.e. not using a comparator)... that is probably the cause of your variances.

A guy can buy a box of "seemingly" match grade bullets, but still see a large swings in measurements in the distance from the Ogive to the Tip..... always measure Cartridge Base to Ogive.
 
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Use the samme bullet. Make sure the case screw is tight for each measurement. Use same pressure for bullet each time. It works every time.
 
The tool could have been better if the rod was made of metal (any metal) instead of plastic.
I am certain that mine will eventually wear out because the plastic.

That issue aside, I take five separate readings using the same projectile using generally the the same steps as you.
The extreme spreads in readings (CBTO method) over the measurements is typically around 0.005 maximum.

However, the first time I ever used the tool was in a 223 with a absolutely filthy chamber and throat.
I was getting highly variable readings in CBOT and I believe that its was a result of debris.

I am curious.... are you measuring the Cartridge Base To Ogive (i. e. with a comparator on the end of your calipers) or are you just measuring to the tip of the projectile after using the guage?

If you are measuring at the tip of the bullet (i.e. not using a comparator)... that is probably the cause of your variances.

A guy can buy a box of "seemingly" match grade bullets, but still see a large swings in measurements in the distance from the Ogive to the Tip..... always measure Cartridge Base to Ogive.

I’m doing CBTO measurements. I’ve tried the OAL method before and agree there is too much variance with HPBT bullets and even the polymer tips like AMAX / ELD.
 
Use the samme bullet. Make sure the case screw is tight for each measurement. Use same pressure for bullet each time. It works every time.

I don’t understand the logic of using the same bullet. The whole point here is consistency for reloading. I was every bullet I shoot to be .020” off the lands. If I use the same bullet for several readings, great, I can seat that bullet .020” off the lands but once that bullet is fired, what do I do with the next bullet? I used 10 different bullets and they all appeared to have substantially different ogive lengths, so then regardless of how I set up my dies, there is now way I can consistently have that .020 jump shot after shot.

Am I missing something here?
 
I don’t understand the logic of using the same bullet. The whole point here is consistency for reloading. I was every bullet I shoot to be .020” off the lands. If I use the same bullet for several readings, great, I can seat that bullet .020” off the lands but once that bullet is fired, what do I do with the next bullet? I used 10 different bullets and they all appeared to have substantially different ogive lengths, so then regardless of how I set up my dies, there is now way I can consistently have that .020 jump shot after shot.

Am I missing something here?

You're not really missing anything, we're just looking at the problem differently.

I've found the best way to solve reloading problems is to eliminate one variable at a time.

By taking several measurements using the same bullet, you are removing the possibility of inconsistent bullets from the equation.

If you do that and still get widely varying results, it's either a technique or measuring equipment problem.

If, however, you take 5 measurements using the same bullet and they're all within a few thou of each other, then you've got bullet problems.

Use a fresh bullet for this and be gentle but firm with it. If there's doubt that it's touching the lands, paint it with a Sharpie marker and look for contact. At a guess, I'd say the amount of force I use to push the bullet to the lands is about a pound or two. Enough that it usually sticks slightly and I have to push it back with a cleaning rod.

To get right down into the weeds, it's highly unlikely that your bullets are that bad. If you think about it, the .26 comparator bushing contacts the bullet very close to where the rifling in your barrel touches.
For there to be over 100 thou difference (from your second set of measurements) in the case head-to-ogive length from one bullet to another, those two bullets would look very different to the naked eye.

To check the bullets themselves, first measure the bullet total length, then use the .26 comparator bushing to measure from the bullet base to the ogive. Subtract the second number from the first. The result is the distance from the ogive to the tip of the bullet. Record those three numbers. Now repeat the process for 4 more new bullets.
Since your seating stem touches the bullet closer to the tip than the ogive, the variance you'll find doing this is roughly what you can expect from these bullets for consistent distance from ogive to the lands.
I occasionally check a batch of reloads to see how consistent my seating depth is. Using 6.5 Sierra Match Kings, there's rarely more than .002" difference in the case head-ogive distance from one round to another.

One thing we haven't talked about is your caliper. Is it measuring consistently at that distance? Digital calipers may read "0" just fine, but start reading incorrectly at an often-used dimension. Try taking something solid, like a loaded round, and measure it 10 times. It should be very close to the same each time.
 
I’ll clean my chamber out and measure up some bullets to see if they are consistently size. Thanks for some tips to help with troubleshooting.
 
First and most important is to understand what the bullet is touching. The throat is a shallow angle tapered cone. The lands are not the beautiful sharply defined things you see in all the diagrams. They are a gradually sloping raised area.

If your barrel is even slightly less than brand new the throat, beginning of the lands, whatever you call it is rough, abraded, cracked. No matter how clean it is it is not smooth. The beginning of the lands becomes pretty obscure after the barrel has seen a few hundred rounds. Take a look at a 6.5 x 284 competition barrel and try to find any lands at all after 2000 rounds.

Best thing to do is beg or borrow a borescope and look.. If you can look at all the throats you can. Take a look at a 22-250 that has 1500 rounds though it then take a look at a new barrel.

The shallow cone you're trying to measure is rough and constantly changing.

Next try using a different technique with the tool. Put some light lube or grease on the bullet, just the thinnest film. With your left hand manipulate the rod on the OAL tool. In your right hand have a 30" piece of wood dowelling down the barrel against the bullet nose. Now you can jiggle the bullet in and out of contact with that cone between both your hands. You can feel it touch and feel it wedge into the cone. Try with everything dry, try it very lightly oiled until you get 10 measurements within a few thou with the same bullet. Then you know your technique is good.

I gave up after 30 years and switched to Erik Cortina's method. Watch his method on his youtube video.

Nobody is giving you bad advice, it's just a very very tough thing to measure accurately, consistently and with repeatabilty.

Brad
 
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