OAL 178 AMAX Criterion 308

[hafejd30]

How far off the lands are you guys noticing your best accuracy with hornady 178 amax.

[hafejd30]

Im thinking of going .010 off the lands to start but wanted to know if those with this barrel/bullet combo could enlighten me on their experiences.

[Dennis]

First, I found a good powder load!

I decided to try some .030 off the lands, I started at .010!

Groups tightened up at .030

So I decided to try some at .050 up to .080

.050 off the lands to MY suprise gave me the best groups, cloverleafs!

Great Bullet, I find the wind will effects these bullet moreso than SMK's or Bergers, but they are very accurate.

[hafejd30]

Thank you for the info. My thoughts are to start at .010 off lands and try

178 AMAX
Lapua brass
BR 2 primer
IMR 4064

41.5g
42.0g
42.5g
43.0g

28" 1 in 10" barrel

Im looking to reach 1000yds without killing my brass. What are your thoughts on the powder charges. Will it be enough? Or should I be looking at higher charges. I just dont want to find and tune a load only to find it wont get to 1000 accurately. Any info is welcome.

[Dennis]

I have the same length and twist.

43.3 "VARGET" is what works for me .050 off the lands.

START off low and work up to this area, you will see your groups tighten up.

Dennis

[nsaqam]

Why not start off right ON the lands?

Work up your loads to where you begin to see pressure with the bullet touching the lands and see if the accuracy is there. If it is, you're golden.
If it's not then you only have one direction to go with seating depth, deeper.
You also know you won't be running into pressure because since you're safe while on the lands, you'll be safe as you back the bullet off the lands.
I didn't develop this technique but it works and eliminates a bunch of variables.

[hafejd30]

Thank you dennis :)

[Dennis]

Why not start off right ON the lands?

You can . . . my personal experience with Nossler NBT's and A/V Max's . . . they don't like being on or in the lands!

Again, this is my personal experience with the two! Most of the time it usually works out around .050 off with the above two bullets, all calibers.

Dennis

[hafejd30]

My previous barrel shot 1/2 moa with 168 amax. .034 off the lands. The closer it got to the lands the worse it shot. I've seen around .010 as a recommendation for the 178. Il try .010 and when I find the charge it likes I'l move it to .030 and .050. and see what it does.

[Dennis]

My previous barrel shot 1/2 moa with 168 amax. .034 off the lands. The closer it got to the lands the worse it shot.

This is my experience with all my current and previous barrels!

Again, with any A-max's, V-Max's, and any Noosler Balistic tips!

Dennis

[nsaqam]

My previous barrel shot 1/2 moa with 168 amax. .034 off the lands. The closer it got to the lands the worse it shot.

This is my experience with all my current and previous barrels!

Again, with any A-max's, V-Max's, and any Noosler Balistic tips!

Dennis


My experience with the 162gr. Amax out of my 26" three groove SS PacNor nutless.280AI Savage was that I got best accuracy kissing the lands. I also got a verified 3050fps at 15' from the muzzle with three different chronographs.
My present 6x47 (6mm-.222 Rem Mag) Kimber also performs best with the 70gr NBT kissing the lands. I can't run them from the mag at that length though so I run them ~.060" off and get MOA accuracy for three slow shots.

[deltagunner00]

Hate to ask it but its the only way to learn. How do I find out how far off the lands I am? I need to do this as I have some good loads worked up. Thanks for the help.

[nsaqam]

Hate to ask it but its the only way to learn. How do I find out how far off the lands I am? I need to do this as I have some good loads worked up. Thanks for the help.


There are a number of ways but each involves first finding where your lands are with the exact bullet you intend to load.
The cheapest way is to size just a very small portion of your case neck so it holds the bullet but still allows it to slide relatively easily into the case. Color your bullet with a Sharpie. Load the dummy round into the chamber and close the bolt. Open the bolt and carefully extract the case. If you're fortunate you'll have four (or however many lands your barrel has) equal size marks all at an equal distance from the tip. Since you colored the bullet you'll also see if the bullet was pulled out of the case a bit as you extracted it. If it did you'll have to size a bit more neck and try again.
Once you're happy with the results of this procedure then you need to measure the length of the dummy cartridge. Measuring to the tip isn't accurate enough. You need a bullet comparator, either the Hornady Comparator or the Sinclair nut type comparator. These will measure to the ogive which is much more consistent than measuring to the tip. Record this dimension as this is the distance to the lands. Seat the bullet deeper and measure with your comparator until you get the distance off the lands you want.

There are a few tools which work well to get the distance to the lands. The Hornady (nee Stoney Point) Case Length Gauge which works from the breech and requires a modified case sold by Hornady or made by you. The Sinclair tool works from the muzzle and utilizes two sliding collars.
http://www.sinclairintl.com/.aspx/pid=35491/Product/Sinclair-Bullet-Seating-Depth-Tool
http://www.sinclairintl.com/.aspx/pid=35663/Product/Hornady-Lock-N-Load-OAL-Gauge-standard-
http://www.sinclairintl.com/.aspx/pid=34262/Product/Sinclair-Hex-Style-Bullet-Comparators
http://www.sinclairintl.com/.aspx/pid=35659/Product/Hornady-LNL-Comparator-Set-22-6mm-25-270-7mm-30-cal

[MrMajestic]

Im looking to reach 1000yds without killing my brass.


You and many others! Just read Laurie's(very knowledgeable Brit) 4 part series in Target Shooter magazine on that. He states most are running the 208 gr. A-Max/210 gr. or heavier Bergers in Palma cases due to the pressures. Of course you need a very long throat to seat them out to maximize powder capacity. Ball powders come into play also for the same reason. He had success with H414/WW760 in a Palma SRP cases due to the burn rate and you can get close to 50 grs. of the stuff in it if you throat it accordingly. Mind you with the long throat you basically have a dedicated tube because the shorter bullets would be like Evil Knievel's Grand Canyon jump!

All that said our Palma boys with the 155.5 grain restriction are using the same case with Varget and shooting 1K. Guaranteed their pressures are high though! Guess cases come under "the cost of doing business"!

[jsthntn247]

I agree with nsam, start on the lands so you know just how hard you can push it until you see pressure then back off. My gun likes 44.9 and 42.8 gr of varget with the 178 amax's. I have to seat the 44.9 .020 off lands for best accuracy and kissing the lands with 42.8. This is with lapua brass. As a side not I got unexplained fliers at the higher node and didn't get them at 42.8 with a speed of 2630 at 42.8. Hope that helped.

[Bamboolongbow]

I shoot those bullets .030 off of lands with 43.8 grs of Varget. My 110 measures 2.290 to the lands.

[hafejd30]

Thank you for the replys. These were my results.

178 AMAX
IMR 4064 43 gr
.015 off lands
Lapua brass
BR-2 Primer
2734 fps
Extreme Spread = 7 fps

1st shot opened group to .5 MOA for 5 shots. Shots 2-5 were inside 3/4" or .25 MOA. Test was 300 Yards

This load with 43 grains was slightly compressed at .010 off lands and obviously more so at .015. The velocity for .010 was 2700 and .015 was 2734. I tried some .025 off lands and it shot .44 moa. Putting 4 shots inside .34 moa and 3 of those into 1 hole. I was hastly shooting these just looking for pressure signs and checking what the bullet would do further from the lands so I didnt take the time to crony.

My final decision is to stick with 43 grains and .015 off lands. I figure as the throat wears the jump will get further on its own. This improved the grouping in my previous barrel which also shot better the further I seated off the lands.

Since .010 to .015 increased by 34 fps I figured that was fast enough and for peace of mind would rather not seat another .010 into the case.

I had the worst group at 41.5 gr seated at the lands which had an extreme spread also of 7 fps. Every load I shot at 43 slightly compressed shot within 15 fps extreme spread.

At 41.5 gr it shot .44 - .46 moa .010 and .030 off lands with higher ES. 40-55 fps.

43 at .010 off lands shot .51 moa.

I tried 42 and 42.5 grains .010 off lands and shot .82 and .92 moa. No further testing was done and this charge.

Again, thank you to all who posted there advice and opinions. It turns out they were spot on. Now to bring the cousins 10 fcp-k to the reloading bench. I will post my findings with that rifle as well to further help those looking for load advice

BTW- this load shoots almost dead on POI as my previous 168 grain load. Thats leaving the scope zeroed after changing out the barrel from the stock 24" to this 28".

hafejd30