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Load development for 308 Howa with 24" barrel

Posted By: Olshovel

Load development for 308 Howa with 24" barrel - 03/19/18 01:17 PM

I will start by saying I am new to reloading. I have been doing a lot of reading, on this forum and on many sites with articles about developing loads for a rifle on the internet. The most interesting thing I have read was a thesis paper titled "Optimal barrel time concept" written by the guy that developed some program for reloading called Quickload. Is anybody here familiar with this program and does it work? I have been reading about nodes and the methods used to determine where those are as you develop loads. Based on the optimal barrel time paper, the COAL had more effect in moving a round towards the nodes than powder charge. Is this consistent with the practical experience that is represented by all of you long term reloaded here? I am about to load up my first round and I'm curious if I need to focus on powder charge first or play with seating depth first?
Posted By: Korean Redneck

Re: Load development for 308 Howa with 24" barrel - 03/19/18 01:41 PM

As fellow newbie, here's my take on your starting point and questions:

As far as finding the best node is concerned, it seems that most do a variation on something referred to as the ladder test. Full disclosure, the follow is my process from a bunch of info fireman sent me.
1. Load 2 of each weight charge of powder in 0.3gr increments. I ended up doing about 8 sets.
2. I seated them all the same depth to start out with, which was about 0.010" behind the lands.
3. Get colored Sharpe markers and paint the who bullet exposed different color for each load. Tip, my sharpie pack was arranged in the color spectrum order. I paint the tips in that order for charges too.
4. I have a 600 yard range available so I shot mine at 300 yard. One of each load at the same target. Hopefully u shot those well.
5. Then ignoring mostly the horizontal spread, find the 2-3 shots that are the closest together vertically. They should be very close in charge weight. Fireman said supposedly he just makes and shoots one of these sets. I make 2 sets and shoot them separately to confirm results.
6. Then what ever range of charges was the best, then make larger groups of just that range in smaller increments.
Posted By: RiverRider

Re: Load development for 308 Howa with 24" barrel - 03/19/18 02:07 PM

The OBT theory may have merit, but it's really too narrow a window to look through in the attempt to develop a load, if you get my drift. OBT focuses on the annular distortion of bore diameter reflecting back and forth and disregards other vibration modes. I think those other modes of vibration are just as important, and maybe even more so. I've done a bit of experimenting with a couple of rifles to see if OBT could be used in conjunction with QuickLOAD to develop a load, and it just has not panned out conclusively---for me.

If you have sufficient range to try the ladder, then it may well work for you. If not, the old 100- or 200-yard method will work also. One wrinkle I have added to my own methods is to shoot two-shot "groups" during initial development, aka "finding pressure." If a load appears to want to spread two shots 1-1/2" then there's no reason to pursue that charge weight. Two shots can't prove a load is good, but they can sure give an indication that it's probably not going to work.
Posted By: RiverRider

Re: Load development for 308 Howa with 24" barrel - 03/19/18 02:13 PM

Seating depth can have quite a bit of effect on a load's performance, too. A good place to start is 1/10 of a caliber off the lands.

Sometimes you just can't get a bullet anywhere near the lands, but that doesn't mean you won't be able to develop a load that will shoot. If you find yourself in that situation, just start at max OAL allowed by the magazine, and seat a little deeper from there if necessary.
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 02:17 PM

Originally Posted By: Korean Redneck
As fellow newbie, here's my take on your starting point and questions:

As far as finding the best node is concerned, it seems that most do a variation on something referred to as the ladder test. Full disclosure, the follow is my process from a bunch of info fireman sent me.
1. Load 2 of each weight charge of powder in 0.3gr increments. I ended up doing about 8 sets.
2. I seated them all the same depth to start out with, which was about 0.010" behind the lands.
3. Get colored Sharpe markers and paint the who bullet exposed different color for each load. Tip, my sharpie pack was arranged in the color spectrum order. I paint the tips in that order for charges too.
4. I have a 600 yard range available so I shot mine at 300 yard. One of each load at the same target. Hopefully u shot those well.
5. Then ignoring mostly the horizontal spread, find the 2-3 shots that are the closest together vertically. They should be very close in charge weight. Fireman said supposedly he just makes and shoots one of these sets. I make 2 sets and shoot them separately to confirm results.
6. Then what ever range of charges was the best, then make larger groups of just that range in smaller increments.


I shoot 1 round of each powder charge in a ladder test.
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 02:24 PM

OP,

I will find rifling, seat. 002" to .005" short of the lands, then check if it will fit in the magazine. If it will, then I test powder charges. I am in the camp that the powder charge is the most important factor. For too many rifles I've seated to a rifling relationship, tested powder charge, found the right one, and called it a done project. For the guy that still thinks he needs to squeeze out a better load, I say keep your BEST powder charge, then play with seating depth variations.

I have a policy of not jamming in the lands, touching maybe, but not jamming. In the case of the loaded cartridge that needs to be ejected, I've seen my rifles, and other shooter's rifles eject a case, sling powder everywhere, and now we have to get a cleaning rod to remove the bullet. So when I'm talking about testing seating depth, I am saying testing progressively farther from the lands.
Posted By: Olshovel

Re: Load development for 308 Howa with 24" barrel - 03/19/18 02:47 PM

My max OAL is 2.890 as measured with the hornady tool and one of their special cases, using a 168 hornady bthp. I have not measured yet to see if that will fit into my magazine yet. I am running a PTG bottom metal. I am going to use a comparator and measure off the ogive to set it off the lands the distance suggested and then work powder loads. Would you suggest starting in the middle of the range and work up or start at the bottom and work up?
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 03:18 PM

Originally Posted By: Olshovel
My max OAL is 2.890 as measured with the hornady tool and one of their special cases, using a 168 hornady bthp. I have not measured yet to see if that will fit into my magazine yet. I am running a PTG bottom metal. I am going to use a comparator and measure off the ogive to set it off the lands the distance suggested and then work powder loads. Would you suggest starting in the middle of the range and work up or start at the bottom and work up?


What powder? And are you using that 168 BTHP?
Posted By: Olshovel

Re: Load development for 308 Howa with 24" barrel - 03/19/18 05:47 PM

Varget is what I have for powder and I am using 168 hpbt's. is the varget going to work well or is there a powder that will do a better job of filling the cartridge with so little of the projectile seated in the case?
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 06:01 PM

Originally Posted By: Olshovel
Varget is what I have for powder and I am using 168 hpbt's. is the varget going to work well or is there a powder that will do a better job of filling the cartridge with so little of the projectile seated in the case?


The best powder on the face of the earth, for bolt action .308 is H-Varget as far as I'm concerned.

Let me save you some time, test fire from 44.5 gr up to 46.0 gr.
Posted By: Olshovel

Re: Load development for 308 Howa with 24" barrel - 03/19/18 06:35 PM

I will start there, thanks for the input. So run a ladder on charges, find what is accurate and then come back and play with seating depths?
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 07:44 PM

Originally Posted By: Olshovel
I will start there, thanks for the input. So run a ladder on charges, find what is accurate and then come back and play with seating depths?


Shoot a ladder, find where the node is. What three charges grouped together. Go load those for 5 shot groups, if you have the barrel contour to hold 5. Shoot those as groups, tighest one is your powder charge. Keep that charge, and then play with seating depth if you are so inclined.

Ladder tests are the most efficient when you can load, at the range. Learn what you need in the ladder, and immediately load groups, and shoot them right away. That is why I have a loading facility attached to the rifle range.
Posted By: Olshovel

Re: Load development for 308 Howa with 24" barrel - 03/19/18 08:15 PM

Thanks Fireman. Where is your range located?
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 08:50 PM

Wolfe City, TX
Posted By: ChadTRG42

Re: Load development for 308 Howa with 24" barrel - 03/19/18 08:53 PM

Originally Posted By: FiremanJG
Let me save you some time, test fire from 44.5 gr up to 46.0 gr.


This is good info. But, depending on what brass and primer you are running, the 44.5 grains can be a little high as a starting point. I'd start about a grain less and work up to make sure everything is safe.
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 09:28 PM

Originally Posted By: ChadTRG42
Originally Posted By: FiremanJG
Let me save you some time, test fire from 44.5 gr up to 46.0 gr.


This is good info. But, depending on what brass and primer you are running, the 44.5 grains can be a little high as a starting point. I'd start about a grain less and work up to make sure everything is safe.


Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/19/18 09:28 PM

Originally Posted By: ChadTRG42
Originally Posted By: FiremanJG
Let me save you some time, test fire from 44.5 gr up to 46.0 gr.


This is good info. But, depending on what brass and primer you are running, the 44.5 grains can be a little high as a starting point. I'd start about a grain less and work up to make sure everything is safe.


Come on man!!!
Posted By: wp75169

Re: Load development for 308 Howa with 24" barrel - 03/19/18 11:35 PM

Originally Posted By: ChadTRG42
Originally Posted By: FiremanJG
Let me save you some time, test fire from 44.5 gr up to 46.0 gr.


This is good info. But, depending on what brass and primer you are running, the 44.5 grains can be a little high as a starting point. I'd start about a grain less and work up to make sure everything is safe.


Just looked. 44.3 was the most accurate in mine with this bullet and powder. When I went to the 178s I actually wound up with a higher powder charge of varget and better groups.

As fireman said Varget is the powder (in my opinion) for the .308

I think going any heavier than 178s in the .308 is a loss. You lose so much case capacity you just can’t push the heavies like they need to be pushed.

Note: I am a 100% self taught reloader. My information all came from books and the helpful people here. That and experience. So i definitely consider myself a novice.
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/20/18 12:44 AM

44.0 to 45.0 gr. for 178's

45.0 to 46.0 gr. for 165's, 168's

If I hit pressure early for some reason, I'll work below that.
Posted By: Olshovel

Re: Load development for 308 Howa with 24" barrel - 03/21/18 10:26 PM

So I got my six rounds loaded up for my ladder test. I have the bullet seated 10 thou off of the lands, which has my COAL too long to fit into my pmags. I don't know whether the current COAL would fit into a metal aics style mag or not and I am curious about the following;
- once I determine the powder charge that is most accurate, and I go back to reload bullets with a COAL that will fit into my mags, how much effect is that going to have on my accuracy that was determined with the longer bullets? I assume the change in jump to the lands and change in velocity could have an effect on accuracy? Should I start out with the longest length that will fit into my mags and not worry about starting at .010 off the lands?
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/21/18 10:48 PM

Make it fit in the mag before shooting test loads. If you run long, learn a charge, then shorten O.A.L. you would need to shoot the ladder all over again. You would have changed something after the test firing.

Pick a length, then go find powder charge. Find some charges that look good, and keep the length you had to go to, to fit in the mag.
Posted By: Olshovel

Re: Load development for 308 Howa with 24" barrel - 03/22/18 11:45 PM

I am going to load up 6 more at the length they have to be like you suggested, but shoot the first six just to see what happens. I noticed that the Lee loading manual has a never exceed for a 168 grain jacketed bullet of 46 grains in the Varget. The Hornady manual on the other hand has a never exceed of 44 grains for this particular bullet. Should I be wary of my last couple of loads at 45.5 and 45.8 grains? I will also be shooting these through a chronograph.
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/23/18 02:03 AM

So, Hornady's lawyers are more scared than Lee's. More than once I've loaded for .308's, 168 gr up to 46.0 gr and 178 gr up to 45.0 gr.
Posted By: DStroud

Re: Load development for 308 Howa with 24" barrel - 03/23/18 02:15 AM

Not for everyone but I run the 200 gr Berger in my .308 with Varget at 2655fps.
Posted By: Buzzsaw

Re: Load development for 308 Howa with 24" barrel - 03/23/18 03:03 AM

you don't need no stinkin ladder. just pick one of these and be done with it, preferably 46.0 if I remember back to my .308 days

The best powder on the face of the earth, for bolt action .308 is H-Varget as far as I'm concerned.

Let me save you some time, test fire from 44.5 gr up to 46.0 gr.
Posted By: scottfromdallas

Re: Load development for 308 Howa with 24" barrel - 03/23/18 03:10 AM

Originally Posted By: DStroud
Not for everyone but I run the 200 gr Berger in my .308 with Varget at 2655fps.


Wow, I can't; even get that velocity with 200 grain bullets from a 338 Federale.
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/23/18 11:45 AM

Originally Posted By: Buzzsaw
you don't need no stinkin ladder. just pick one of these and be done with it, preferably 46.0 if I remember back to my .308 days

The best powder on the face of the earth, for bolt action .308 is H-Varget as far as I'm concerned.

Let me save you some time, test fire from 44.5 gr up to 46.0 gr.


^^Drunk post.

Ignore this.
Posted By: Olshovel

Re: Load development for 308 Howa with 24" barrel - 03/23/18 10:05 PM

One last question before I go shoot these rounds, I see where some of you recommend shooting a target at 200 yards instead of 100 when you are working up loads. What is the reason for that. Also, thanks for all the input. I hope to have a couple of targets to post up after this weekend, hopefully I will do my part well!
Posted By: J.G.

Re: Load development for 308 Howa with 24" barrel - 03/23/18 10:50 PM

If you're shooting groups, it is easier to decipher a good load from a bad load at 200 yards versus 100 yards.
Posted By: Buzzsaw

Re: Load development for 308 Howa with 24" barrel - 03/23/18 10:56 PM

make sure the wind is blowing 20 mph, should really help your ladder testing bolt
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