223 Max. seating length

[KMW 1954]

This should be fun. Don't know what I am going to find or where this is going to lead.

I have a Savage Model 12 barrel that I have been shooting for awhile and mostly with Sierra MK 69GR. Now I took a break from this to work with my 6ARC but have now gone back because it is much cheaper to shoot and stay sharp.

I had a few boxes of 68gr Hornady Match and 69gr Nosler Comp that I haven't been using and wanted to just use up. Now since I haven't loaded or shot these for over a year I nearly started over, though I had a baseline load to start with.

I started this by once again looking to find the bullet touch point for both the Hornady and the Nosler bullets. What I quickly found was touch was extremely long. Now this rifle has a blind magazine that is also extremely long. The numbes I have come up with are just what I have found on this particular rifle and with my Hornady comparator. So don't try to duplicate this.

With the Hornady bullet I was able to push this all the way out to 1.966" BTO to reach touch and didn't even try to find it with the Nosler. But I did find that I had to move both bullets back to a length of 1.9035"BTO in order to get them to feed into the chamber w/o hitting low on the the barrel. Now even at this length they are way past the 2.260" general mag length.

I have 10 of each bullet type loaded at this length and will tomorrow see how they perform and compare them to a normal load which is the same powder charge.

 

[KMW 1954]

A quick observation after shooting these today. The 68gr Hornady still suck dirt.

 

[Jeff Porter]

These bullets really don’t gain much by seating close to the rifling. May actually see smaller groups seating them in to 2.235” -2.240”.

 

[KMW 1954]

These bullets really don’t gain much by seating close to the rifling. May actually see smaller groups seating them in to 2.235” -2.240”.

Tried that too, long ago. Results were not much better then either..

 

[jelenko]

Both should shoot into < 3/4 MOA groups. I've shot both into .4 MOA groups from time to time.

 

[Coyotefurharvester]

You probably need to do an actual seating depth test. Nosler data suggests 2.260, hopefully someone more experienced can provide a method to test -0.020 to + 0.030 coal. Or use the Berger method?

 

[Jeff Porter]

So what is your overall length when the 1.9035” maximum CBTO is used?

 

[JB10]

I have a 12fv in 223. I shoot 73gr eldm bto is 1.933 just barly off lands. Shoots great. Coal is 2.377. Still fits on blind mag and feeds good. Looks long though

 

[KMW 1954]

Both should shoot into < 3/4 MOA groups. I've shot both into .4 MOA groups from time to time.

I've tried both these bullets in 3 different rifles, all of which with SMK or Matchburners will easily shoot under .5MOA. The Nosler will shoot .5 with the proper load. I have given up on the 68gr Hornady. Part of this test was just to see how they would react when compared to the shorter length Nosler, and others.

Best I could get today with the Hornady loaded this way was 1.5MOA @ 200yds. while the Nosler were at just over .5MOA which surprised me at this length and powder charge.

 

[KMW 1954]

You probably need to do an actual seating depth test. Nosler data suggests 2.260, hopefully someone more experienced can provide a method to test -0.020 to + 0.030 coal. Or use the Berger method?

Reread the first post where I explained the reasoning behind this. This wasn't designed to find a great load.

 

[KMW 1954]

I have a 12fv in 223. I shoot 73gr eldm bto is 1.933 just barly off lands. Shoots great. Coal is 2.377. Still fits on blind mag and feeds good. Looks long though

I could get to the 1.933" length but they would not reliably feed from the mag to the chamber.

 

[KMW 1954]

So what is your overall length when the 1.9035” maximum CBTO is used?

Sadly I shot them all up today and did not measure a COAL but I can load another and get back to you!

 

[Jeff Porter]

What powder were you using ?
I have had better luck with the Nosler 69 than the H68 in gas guns too. I’d run 23.5-24.0 of H4895 or 8208 with those seated 2.235” in a Wylde. NCC were about 1/2 moa from a 20” AR, 68’s just under 1 moa. I would use Lapua scenar L with that load and would get sub 1/2 moa groups at 300.

 

[jelenko]

68’s just under 1 moa

This reminds me. Hornady replaced a couple 4K count boxes because 'they didn't meet their accuracy specs'.

Do you find that other Hornady bullets produce consistent accuracy?

 

[Jeff Porter]

This reminds me. Hornady replaced a couple 4K count boxes because 'they didn't meet their accuracy specs'.

Do you find that other Hornady bullets produce consistent accuracy?

I have become a bullet snob according to Scott Schneider. As I have focused on belly shooting more, I have determined that lot to lot variation in Red and Green boxes is more than I see in Yellow boxes... For any thing I pay an entry to shoot, Berger's will be going down range. I do shoot Red box stuff in club shoots and for hunting though. Most of the time they go exactly where I point them.

 

[KMW 1954]

Morning Folks!

To answer Jeff's question and a few other measurements.
@ 1.903" measured with a Hornady comparator the Hornady measures 2.315" COAL and the Nosler is 2.320"

BTO of the bullets themselves; Hornady, .5665". Nosler .5160". so the Hornady is .0505" longer.

Chrono speeds using a Magnetospeed. Sorry only had speeds of the Nosler loaded at both lengths available.
Normal loaded length, Avg., 2869, SD 5, ES 12
Loaded long, Avg., 2875, SD 12, ES 28

Hornady loaded long.
Avg., 2924, SD 27, ES 77.. That is loaded with the same components and powder charge as the Nosler. So it looks as though the extra length of the Hornady bullet did effect speed.

 

[KMW 1954]

For this test the powder I am using is Accurate 2460 which is what I have been using when I worked up this bullet. Not that I think the powder has much bearing as I could have used any of 4 different powders to do this.

When I was shooting this rifle in our local league I was shooting 69gr SMK with this same powder or Benchmark when I could get it. It was shooting under .5MOA out to 300yds. The last year I shot this rifle I was using 60gr Hornady VMAX that shot just as good to 200yds but struggled at 300yds.

 

[KMW 1954]

Now part of this whole exercise is in response to another topic here on loading to max length and jamming or jumping bullets. In this case I found I could actually chamber a round that is even much longer than this to reach the lands and still close the bolt and extract w/o sticking a bullet.

So instead of loading to touch I decided to load seat these to a length that would reliably chamber from the magazine. Which brought me to the measurement of 1.903" BTO.

 

[KMW 1954]

Here is a copy of the target from yesterday. All shot from 200yds.

 

[CA48]

I run Hornady 75gr bthps in my factory sav12 223rem. Have to load 2.4” coal, that’s just off the lands with that bullet. But the blind mag will let you run around 2.450-2.500”
I put in an xlr chassis and run aics mags now. When in factory form it feed everything from 40gr - 75gr bullets with no issues, It shoots well.