Issues with measuring OAL

MadMarty

MadMarty

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So Ive posted for help on another forum, but figured it wise to ask here too.
I have a new Savage Model 12 1in9'' twist that Im loading for
So I'm trying to figure out my OAL for my .223 using the Hornady OAL gauge and the hornady bullet comparator. I've taken multiple measurements using the modified .223 case and a 40 grain V-max.

The question I'm having is whether a spread of .037 is normal? Here are the measurements I've taken this far :
1.866
1.859
1.855
1.862
1.856
1.849
1.844
1.860
1.829
1.858

Do I just taken the mean average and say that's my OAL where the ogive touches the rifling?

I have several other bullet choices that I'm hoping to measure today as well.
Your input is appreciated!
 
I just take a once fired case that the bullet fits snug into the neck, close the bolt and remove, i can usually get .001-.002 accuracy, other times it can still stick the bullet in the lands when you remove it
 
My bulletin comparator measures from the ogive. I'd prefer to not use homemade methods as I just spent a bunch of money on these tools. Just wondering about tips on using the tools to get more consistency.
 
I'm within 0.001 every time.
Is the modified case screwed tightly in the tool?
Are you holding the modified case firmly while you gently push the bullet into the lands and lock it in place?
 
thump_rrr said:
I'm within 0.001 every time.
Is the modified case screwed tightly in the tool?
Are you holding the modified case firmly while you gently push the bullet into the lands and lock it in place?
Click to expand...

X2 . A light touch is required and painting the bullet ogive with white board marker confirms contact with the lands.
 
I'm not a serious reloader (plinking), so I just use a factory .303 round and measure the OAL on that and use that as my guideline
 
OP, your title states you are having head space trouble.
But in the text you are discussing how deep to seat the bullets.
This has nothing, whatsoever, to do with headspace in the rifle.
 
MadMarty

I have a Stevens 200 .223 with a heavy 26 inch barrel, go back to http://www.accurateshooter.com/ and read about "jamming" your bullets into the rifling.

1. I'm getting my best accuracy by jamming the bullets hard into the rifling.
2. These Savage/Stevens .223 rifles have longer throats than my AR15 rifles do.
3. Savage .223 freebore length .0566
4. SAAMI standard freebore .0250
5. Military 5.56 freebore .0500
6. Don't drink coffee before taking your measurements. (shakey hand syndrome) :cheers:
 
I guess I used the wrong term. Thanks to our resident "word" nazi I will endeavor to never misuse a term again ;)

As it stands I tried again today with 3 different types of bullets. Across all 3 I had an even larger deviation - up to .070 in measured lengths on each bullet. I'm at my wits end and even taught my wife what to do just to see if it was me, she received large spread between measurements as well.
 
I would suggest loading up some ammo and go shooting. You can always play around with seating depth later. Might not make much difference.
 
MadMarty - I just obtained a Hornady OAL length gauge as well and have pretty much the same rig you're working with (Savage M12, .223).

I have found that the OAL gauge gives very consistent results with some bullets (i.e. Sierra 69gn Match Kings), but isn't nearly as consistent for others (i.e. Lake City 55gn). I'm wondering if the issue is the lighter and shorter bullet getting mis-aligned inconsistently in the throat before jamming in the lands due to less bullet being still in the neck of the cartridge. I get variations of about .001 with the SMK's, and about .01-.02 with the lighter ones.

Anyway, as the SMK is my go-to bullet, I don't mind too much about the others not working as well - sure would be nice if they did, tho...
 
I had the same experience in my .308 Using 168gr SMKs, I got the same result to the thousands, 8 out of 10 attempts. Using 155gr Palma, it was more varied. For gits and siggles I tried with Berger VLDs, and it was all over the place, too easy to jam unintentionally.
 
Here's how I measure for COAL. Keep in mind that this must be redone for different bullet brands/shapes. Size several cases and seat them with bullets that are a little over your expected COAL. (make sure you use unprimed, empty cases!) chamber the rounds carefully and extract slowly. Don't let the ejector toss them. If you find them too hard to chamber when closing the bolt, seat them a bit deeper and try chambering again. If you get a bullet that gets stuck on the rifling just tap it out with a rod. once you get 5 or 6rounds that have been chambered, put the calipers on them. Any identical measurements you get from your group of 6 is the absolute COAL for THAT bullet case combo. Now set your seating die to seat at whatever length you choose that is less than the COAL.
 
I've thought about getting one of these things for years but was never sure if it would be worth it or not. It seems by the sounds of things that it is a little more accurate or consistent than the methods I'm currently using. Though to be fair I'm using Hornady SP bullets with a lead tip that doesn't seem to be as consistent as say maybe, an FMJ of some kind. I was loading these up yesterday and noticed within 10 rounds an extreme COL variance of up to 0.010".

I checked out several places online trying to find one of these Hornady OAL gauges but to no avail...

Anybody have an idea where I can get one?
 
Siggy Stardust said:
I checked out several places online trying to find one of these Hornady OAL gauges but to no avail...

Anybody have an idea where I can get one?
Click to expand...

Budget Shooter Supply (site sponsor and really good folks to deal with) gets them in at recurring intervals - that's where I got mine.

I believe they should be getting in some more fairly shortly - I got the last one in stock a week or two ago, and the word at that point was that they would be getting more in a couple of weeks. You can try e-mailing Harry at info@budgetshootersupply.ca asking about inventory status.

Good luck!
 
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