Hornady L-N-L OAL guage -- what am I screwing up?

[mattj]

Picked up the Hornady Lock-N-Load (formerly Stoney Point) OAL gauge in hopes of streamlining the process of finding my seating depths. I'm using the curved version on Zediker's recommendation.

Plan was to use the gauge to find my touching-the-lands depth to more quickly "zero" my micrometer seating die. The experience with the tool so far has been a bit... baffling.

I'm hoping that somebody can tell me how I'm being an idiot....

Here's my procedure:

I screw the dummy cartridge into the gauge, put one of my bullets in there seated extremely deeply to start, and push the piano wire plunger until it touches the base of the bullet. I insert the dummy cartridge all the way into the chamber, and maintain enough pressure to keep the case shoulder in contact with the chamber. I then push the piano wire plunger to increase the seating depth of the bullet in the dummy cartridge until I feel resistance, and then tighten the thumbscrew to lock the plunger at that depth. I remove the device from the chamber -- sometimes the bullet comes out, sometimes I have to gently tap the butt of the rifle on the ground to knock it free.

After removing the gauge, I re-insert the bullet until its base is touching the plunger, and then use the Hornady LnL bullet comparator to measure the length of the dummy cartridge + bullet, indexing off the ogive.

So, the seating depth of the bullet in the OAL gauge's dummy cartridge when I follow this procedure (measured in terms of bullet base to ogive) *should* correspond to the seating depth (again, measured in terms of bullet base to ogive) where a loaded cartridge would be just touching the lands... right?

But here's the head scratcher:

If I load a cartridge to that seating depth, the bolt will not close. I have to seat the bullet almost .2" deeper in order to get the bolt closed.

The problem isn't head space or neck length, because I can chamber the brass before loading the bullet, and if I keep increasing the seating depth, I eventually get to where I can close the bolt...

I've tried this multiple times -- using different individual bullets and brass and have obtained the same results.

Everybody seems to think the OAL tool is be best thing since sliced bread, so I'm sure I'm doing something wrong -- but I'm stumped as to what my folly here could possibly be.

Any ideas?

Thanks,

Matt

 

[gahlizard]

are you using one of their generic dummy cartridges or did you send them one fired out of your rifle?

 

[mattj]

Using the generic one -- though I'm also using fresh full-sized brass.

You're right though -- it had not occurred to me that the depth the bullet ends up seated in the dummy bullet will be directly affected by the head space of the dummy cartridge.

Sounds like I need to compare the headspace of my real brass and the dummy cartridge.

Thanks for the insight.

 

[mattj]

Hmm, the dummy cartridge measure the same as my sized brass on the Hornady headspace gauge -- though that indexes off of just the one point on the shoulder, I suppose it could still "bottom out" against the chamber at a different point than the brass if it is not shaped correctly.

 

[loaders_loft]

I use the straight version because I only use it for bolt action rifles.

For the straight model, Hornady's website says, "For all bolt action and single-shot firearms, or any firearm with straight-line access to the chamber. This model is preferred, as it is most precise and user friendly."

For the curved model, Hornady says, "For all autoloader, lever-action, or pump-action rifles. Also fi ts all bolt-action and single-shot firearms. Inserts into chamber through ejection port."

If yours is a bolt action, maybe you should abandon the curved model and get the straight model?

I take 3 measurements when using a new bullet. Sometimes I get an artificially high number, from applying too much pressure and jamming into the lands. It only takes a slight pressure to contact the lands. Maybe you're applying too much pressure and buckling the "paino wire plunger" within the tube, which would amount to excess length, thereby artificially extending your COL.

Another thought - take your measurements with a comparator instead of measuring from the bullet tip.

 

[mattj]

I use the straight version because I only use it for bolt action rifles.

For the straight model, Hornady's website says, "For all bolt action and single-shot firearms, or any firearm with straight-line access to the chamber. This model is preferred, as it is most precise and user friendly."

For the curved model, Hornady says, "For all autoloader, lever-action, or pump-action rifles. Also fi ts all bolt-action and single-shot firearms. Inserts into chamber through ejection port."

I went with the curved version because Zediker recommends it for all rifles in his book, said he found it to be the more consistant of the two versions, and works fine in bolt guns.

I don't see any reason why the curved design should be the problem in a bolt gun.

I am using the comparator to measure the seating depth, and get pretty close results over multiple attempts at using the tool.

Good point on bending the piano wire -- I don't think I was pushing it very hard, but I will try again when I have a chance, concentrating on using the super light touch.

Thanks for the reply.

-Matt

 

[longrange.270]

What I did to find my OAL, was after I had fired some brass to my chamber, I neck sized them only. But just enough that you can put a bullet in the neck and it not fall out and is somewhat easy to push in, but still enough tenson. Then chamber the round in the gun and then when your taking it out, be careful not to push the bullet into the case anymore and then measure it and subtract .010, ten thousands, from that number and your good to go. But as long as you get the number after pulling it then you can go from there. I did it a couple of times just to be sure it was right. Sometimes the bullet will get stuck in the lands, but big deal. Here is the video to were I learned how to do this: YouTube - Making a Overall Length Guage or just search youtube for making a overall length guage. Hope that helps any.

 

[loaders_loft]

Okay, good luck and let us know what you find.

 

[cuutter]

The one thing wrong with the vid. is he tells you to load the bullet .100" shorter and I think he means .010". That would make more sence.
Just my two cents.
Good luck
Wayne

 

[johnnyk]

mattj,
I have both the straight and curved tool. I have occasionally had difficulty with some of the dummy cases not fitting in the chamber exactly like they should. I lube 'em up and run them through the FL die. This may not be the best method, as afterwards you have to open the neck of the dummy round back up in order for the right caliber bullet to freely slip in/out of the dummy case.
This usually is not a problem if you have other caliber dies. Simply take the expander ball from another die (one size up) and swap it to the die used on the dummy case giving you the problems. I had trouble with my son's .260 Rem Mtn Rifle and just recently with my .270 WSM Coyote. Both cases gave me erratic readings no matter how hard I tried to control the pressure I applied to pushing the bullet into the LaG's. They both work like champs now.
About the curved/straight tool. I have always used the straight one for all my rifles except for the Browning BLR my dad left me. Of course I have to use the curved one for it and I didn't like it. Anyway, my straight tool recently broke right where the threads meet the tube, so I used my curved one on one of my bolt action rifles. I definately do not like the curved one with the "pianie" wire. Guess it'll take some getting used to but I plan on buying another straight tool asap (I wonder if Hornady will warrantee one of the older Stoney Point tools?). Doubt it. Happy reloading, JohnnyK.

 

[misterc01]

Old Post, but for some reason I have had a problem finding the seating depth with some the OAl gauge and Berger VLD bullets. Using a case I sent to Honrady and had them modifed, also Honrady comparatator. I have gotten measurements from 2.083"n to 2.196"!! I seated some bulletss from 2.158 incehs to 2.192 inches and they ALL chambered fine, so I pretty sure I am stil lnto to the lands. I have had zero problems witht any other bullets - including ELD/VLD bullets from other makers. Any thoughts?

 

[quigley257]

Sounds like you may have a tight freebore in your rifle. Coat one of the bullets with sharpie marker and go through the seating/measuring motion. If you see rub marks or marker removed all around the diameter of the bullet, you have a tight freebore which will lead to inconsistent readings. I had a Savage 223 Rem that was almost exactly .224" in the freebore making it nearly impossible to get an accurate measurement using the LnL OAL tool. I ended up using a T-handle to touch up the chamber with a finishing reamer which took care of the problem entirely. The only place the reamer cut during touch-up was in the freebore. That rifle shoots amazing now and the bullets seat cleanly against the lands when using the LnL tool.

 

[misterc01]

Bingo! Once I saw where the the Lands and bullet met - I got the reading I needed. I was surprised at how far in the bullet went in until it met the lands. Thx.

 

[BigMedicine]

I use the straight version in conjunction with the Frankford Arsenal cartridge overall length gage, and when I get both the Hornady and Frankford measurements consistently close, that is the number I go with.