Rifle Chamber Measuring Technique

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Dgunner
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Rifle Chamber Measuring Technique

Post by Dgunner »

Any experience out there with this method? I completed this today with "Blue" Loctite and I think it turned out great. I am very familiar with Loctite as I represented them as one of my product lines for 30 years. I did not know of this method until watching the following link on YouTube

https://www.youtube.com/watch?v=QC0RKTLbdeg
D-Gunner
TexasMac
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Re: Rifle Chamber Measuring Technique

Post by TexasMac »

Here's my method. Rather than a complicated multistep process used by some shooters, my preferred method is to split the neck of a used case with a hacksaw or Dremel-type tool and partially insert the bullet. See figure below. The split neck will hold the bullet in place under tension but will expand and allow the bullet to slide back into the case when the nose contacts the rifling leade. Chamber the cartridge and close the action. Slowly open the action and extract the cartridge. Measuring the overall length of the case and seated bullet results in the maximum cartridge overall length (COAL) with the bullet touching the lands. Subtract 0.005” to allow for a fouled bore. Reusing the split case, the process is repeated if a different type or style of bullet is used or the alloy mix is changed, resulting in dimensional changes to the bullets and affecting the cartridge length.

Wayne

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Kirk
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Re: Rifle Chamber Measuring Technique

Post by Kirk »

You know fellas, it's a lot less time consuming to just put the particular bullet that you want to load in the chamber, lightly push it up to the rifling,
then take your dial calipers and measure from base to end of barrel and then do a little simple math and that is max O.A.L for that particular bullet...

Kirk,
semtav
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Re: Rifle Chamber Measuring Technique

Post by semtav »

For the mentally impaired like me that need pictures, here is what i think Kirk is talking about.

1. Shallow seated bullet. 3.740
oal 1.jpg


2. amount sticking out of chamber .223
oal 2.jpg


final version OAL 3.740 - .223 = 3.517




oal 3.jpg
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semtav
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Re: Rifle Chamber Measuring Technique

Post by semtav »

My last pic isn't quite perfect. should be a touch longer. .
gunlaker
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Re: Rifle Chamber Measuring Technique

Post by gunlaker »

Now now Brian, don't go making a simple process simple :lol:

Chris.
semtav
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Re: Rifle Chamber Measuring Technique

Post by semtav »

Thats Kirks fault
I can only understand directions when someone draws me a picture.

I usually stick a loaded shell in, see if the lever closes, if not I pull it back out and pull the bullet, compress it a little more, reseat the bullet and see if it works.
Usually only take 6 or 8 tries.
Tomklinger
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Re: Rifle Chamber Measuring Technique

Post by Tomklinger »

😂 c’mon you guys! That’s not how Kirk explained it! :roll: Been doing it Kirk’s way for years, it works great! Read it again…..
Tom Klinger
semtav
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Re: Rifle Chamber Measuring Technique

Post by semtav »

Oh yea. He's measuring from the end of the barrel up into the base of the bullet!!!

Told you I can't follow written directions 🤣🤣
gunlaker
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Re: Rifle Chamber Measuring Technique

Post by gunlaker »

There are definitely a few ways to do this. I have used a measure from the breech face technique, but truthfully what I almost always do is make a dummy round with maybe 0.001" neck tension, but definitely too long. Then I gradually seat the bullet until the depth is where I want it for starting my testing. That is pretty fast, particularly when using a competition seating die.

Chris.
kwilliams
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Re: Rifle Chamber Measuring Technique

Post by kwilliams »

I need simple math so here is my solution to determine COAL and wad depth. Made one in .40 and .45 for around a Dollar.
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TGC
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Re: Rifle Chamber Measuring Technique

Post by TGC »

K. Where does the particular bullet go? Tim
TexasMac
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Re: Rifle Chamber Measuring Technique

Post by TexasMac »

TGC wrote: Thu Feb 16, 2023 4:44 pm K. Where does the particular bullet go? Tim
I can't speak for kwilliams but I'm guessing the inserts pictured are inserted completely to the bottom of the case followed by the bullet.

BTW, I've tried several methods, some described in this thread, and there was no technique faster than the split case neck method I posted earlier. Once the case neck is split, slip in a bullet and chamber it. As it's being pushed into the chamber the bullet will slide back & stay in position under tension. No fiddling or adjustments necessary. The same case is reused for other bullets of the same caliber.

Wayne
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kwilliams
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Re: Rifle Chamber Measuring Technique

Post by kwilliams »

Yes, the metal insert bottoms out in case, insert bullet, adjust the screw as needed, in or out to arrive at the "COAL" case overall length. Pull the bullet out then measure to top of insert for the exact wad seating depth. Who wants to slice cut a $4 plus Norma 45-110 case! This is good for GG and PP bullets
kw
semtav
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Re: Rifle Chamber Measuring Technique

Post by semtav »

When you first sent me that picture I thought that was kind of a complicated way of going about a simple procedure.
Wasn't til this evening I realized it was perfect for us that slip fit our bullets. Plus no math or caliper needed.
Just adjust the thing up on a bullet stuck in the chamber til you can just close the lever or in my case til just the rim is sticking out since I like to cam my loads a touch.
Then put the shell/insert in your press and run the compression die down til it touches.
No math or measuring involved.
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