Change 1 variable, changes them all?


PDA






Demos
April 27, 2013, 07:50 AM
Hi guys,
I've been reloading for my milsurp rifles and a few pistols for years now, and I love it. I've always done some load development for them, but I've never gone crazy chasing the best load because I figured my sanity would be worth more than getting 2.5 moa instead of 2.8 in my garand for instance. But now comes the problem. I've got 2 modern rifles that should be capable of sub-moa and I would love to make some single ragged holes at 100yds while still keeping my sanity between making and testing every possible combo of loads and having "I wonder if it would shoot better if ..." in the back of my mind.
My question is, how to go about finding the best load without burning out a barrel before settling on a load? Say I start with how much Varget I want to use for a given COAL using an A-Max and settle on 45gr. Will 45gr stay the best charge as i start varying the COAL, or do I have to test multiple charge weights for every COAL? And then if I want to test a different bullet of the same weight, like a Match King. Will it shoot the best at the same distance off the lands and powder weight as the A-Max or do I start at square one?

I just keep thinking that if one variable will make all of them different and I want to test COALs, 3 bullets, and two powders with 5 shot groups I will shoot 750 rounds in load development (assuming 5 different COAL x 5 different powder weights x 3 bullets x 2 powders). Then God forbid I change primers or bullet weights because I'll have shot out my barrel by the time I work up a load.

If you enjoyed reading about "Change 1 variable, changes them all?" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
jmr40
April 27, 2013, 08:22 AM
You're way over thinking this. There is no reason to re-invent the wheel. If you spend some time on the internet and communicate with others who have tried similar loads you can get a pretty good idea of what works well. I wouldn't use a load suggested on the net without confirming it in a loading manual. But this will get you close. Even then I'd back off a few grains and work up. Lots of sources available online as well.

http://www.alliantpowder.com/reloaders/default.aspx
http://hodgdon.com/basic-manual-inquiry.html
http://www.ramshot.com/load-data/
http://www.barnesbullets.com/information/load-data/

I'd start a post asking for advice about the specific caliber and bullet you want to use. Even the brand of rifle will help. There are lots of people who can offer tips about which powder seems to work best for them. The COAL can depend on the bullet you use, the rifles mag box and chamber. What works best with a Barnes bullet may not be good advice with a Berger. Same with a Winchester VS Remington.

You will get differeing opinions, but if you listen to enough people you will start to see trends about what seems to work best.

kingmt
April 27, 2013, 08:54 AM
Everything changes everything yes but I agree with jmr. Some things just work across the board & others aren't wroth even trying. If you find the best charge node it *should* stay the same as you vary bullet jump. I'd suggest something besides Varget to work with tho.

Walkalong
April 27, 2013, 09:24 AM
The only way to make working up a load easier is practice doing it.

Pick a bullet, then pick a proven powder or two. See if your gun prefers one over the other.

Then play a little with seating depth if you want to. It might make a difference and it may not.

Then try a different bullet if the one you chose doesn't shoot well.

Change one thing at a time so you know what to blame/give credit. Start low and work up and see how it affects groups. Somewhere along the line it will shoot the tightest groups, generally referred to as a sweet spot. There will be more than one sweet spot along the way if you start low enough.

When you have a pretty good shooting load, then you can tweak it by changing primers or seating depth a little to see if it helps or hurts.

Yep, you can burn through a lot of rounds in an endless pursuit of good groups. Part of load testing is knowing when to quit. :)

beatledog7
April 27, 2013, 09:58 AM
Most of us eventually figure out that the last few increments of precision/accuracy/consistency that can be had from handloading are useful to a very few really good shooters.

I'm not good enough, even from a bench, to be able to discern between a load that can potentially shoot to .5 MOA and one that will never be better than .75 MOA.

Are you?

Walkalong
April 27, 2013, 10:03 AM
Bingo. :)

kingmt
April 27, 2013, 10:32 AM
Isn't that why we reloaded? "For the never ending what if"

That is why I load & shoot. If it want for that & watching my wife & kids enjoy it I'd quit a long time ago.

ranger335v
April 27, 2013, 07:56 PM
There's no justification to shooting five rounds for each load factor test. If the first two are 2 inches apart shooting rounds more won't make it any better.

engineermike
April 27, 2013, 08:15 PM
Once you establish the jump for each bullet shape, just adjusting the powder should be all you need. This is assuming you have the bullet that your rifle likes. :banghead: "DAMN YOU RELOADING" Knitting would have been a better hobby... :)

jmorris
April 27, 2013, 10:30 PM
The single most important variable I have ever read about or seen is the person pulling the lever/setting up.

Unless you have an old rifle with a " burner" round you can find a best load. The key is changing only one thing at a time.

Demos
April 27, 2013, 10:41 PM
Thanks for the input guys, I'll have to take a look at some proven loads for .223 Wylde (AR w/ 20" Lothar Walther barrel 1/8 twist) and a Savage 110 in 30.06. The hard part will be deciding what "good enough" will be since I've never had a chance to shoot a proven platform to see just how much of the group size is me.
Here is what I have on hand if any of you have some advice
Varget, RL15, H4895.
In .224 I've only have some Hornady 55gr SP and 50gr V-Max
In .308 I've have 155gr Amax, 168gr A-Max, 168gr Match King, 168gr Hornady BTHP, and 178 A-Max

jr_roosa
April 27, 2013, 11:06 PM
I'm not good enough, even from a bench, to be able to discern between a load that can potentially shoot to .5 MOA and one that will never be better than .75 MOA.

Are you?

I agree. I obsessed for a while on Garand loads with a couple of proven bullets (168 and 175 match kings) and a few good powders (4895 4064 and VV-N150) and found loads that shot a little less than 2.5 MOA and I was pretty happy.

One day I got a little better with my prone position, and holy cow! I shot a couple of sub 2 MOA groups. Then one day I found a bench setup that worked for me and I got close to 1.5 MOA.

So, now that I know that my technique has improved, I can go back and tweak powder weights a little since I know that I am close to a sweet spot from earlier testing and see if I can squeeze another 0.5 MOA out of the system. Maybe I can, maybe I can't, but I only need to test maybe 3 or 4 strings of 10 shots for each bullet to fine tune my loads.

As for your loads, I would say take the 168 match kings (proven bullets out to at least 300yds) and your 4895 (proven powder in .30-06) and run from min to max in 1.5 or 2 grain increments with 5 shot groups and see what you see with a standard seating depth (measure this with a bullet comparator so you don't go nutty chasing OAL variation from the bullet points being inconsistent).

If you get a 1moa group in there, then you know your technique is OK. If you don't, then take the smallest group and maybe try some with 0.5 grain steps above and below that and see what you get, maybe with 10 shot strings. Once you get the tightest group there, keep it and shoot it for a while as your technique improves.

Next see if the 168 Hornadys perform the same or better at around the same velocity as your match kings. When you get bored shooting tight groups at 168, try the 178s or the 155s the same way. Then start messing with figuring out where your lands are and vary seating depth. Then maybe see how your other powders perform around your velocity sweet spot you found for each of your bullets. Then do the same process for your AR. Then, all the sudden you will have a new rifle and it starts over again!

It never really ends. You chase a load until you get sick of load developement, then you shoot until you start to wonder if you can get smaller groups, then you buy some new gadget that lets you adjust another variable (chrony, bullet comparator, concentricity gauge, etc.) then you have some AH HA! moment and decide to rework all your loads, then you get sick of that and shoot for a while....

Then some politician tries to ban guns and all you can find is 1 pound of powder you never heard of before and you have to work that up too...

It never, ever, ends.

-J.

jr_roosa
April 27, 2013, 11:23 PM
Oh, forgot to add, for 168 SMKs I like 47.5gr of IMR 4895 (slightly different powder than H4895) seated at 2.750" measured using a .30 cal bullet comparator. This runs about 2700 fps. It's a Garand safe load, so you may find a sweet spot at a faster velocity than that. You may also find the velocity spread annoying because of all the extra airspace in the case with this load.

Last time I tested, I got an extreme spread of 44 fps and an SD of 22 fps with a five shot group. That group measured 2.33 MOA at 200 yds prone with a sling out of a Garand with a GI profile criterion barrel, GI chamber cut, national match sights, and no stock bedding. I get better groups with the 175s with my rifle. Your rifle will likely do much better than this with a scope and a good bench technique.

-J.

engineermike
April 27, 2013, 11:52 PM
Oh yea, and then there is technique. :banghead: If it isn't one thing it's another...:)

gamestalker
April 28, 2013, 01:23 AM
What I do is start some where around a mid range powder charge with the bullet at, or barely off the lands. I walk it back in .010" increments until I have found the best group, usually this happens some where within the first 2 or 3 five shot groups. Then I begin working the powder charge up until I've attained what I'm desiring in terms of velocity, and group. Often the slower burning powders, at the upper end of the load table, is where I find what I'm looking for. But that's in my actions, and my desired expectations too.

Of course I start with matching head stamps, and brass that is all trimmed to matching lengths, properly head spaced (.002"), and using the same primmer.

Maybe I've just been plain lucky, but I can often get it done with 3 or 4 five shot groups. And even if does take a bit more work with this, or that component change, it's reloading, and that is what I enjoy about the hobby.

GS

kingmt
April 28, 2013, 09:45 AM
I'd leave the Varget in the shelf while testing for small groups. It just won't do it. I don't know about 4895 or any of the RL powders. If you want to take one varible out use BL(C)-2 it is one of the powders that works in everything. It gets the smallest groups in my 223, 30-06, & 243.

flipajig
April 28, 2013, 01:09 PM
Just to give you another variable is the man on the trigger.
I'm into Specialty Pistols and have been shooting them for quite some time and I have been able to shoot sub MOA 3 times in several trips to the range. When this happens I feel like I have walked on water and the stars have aligned in my favor.
Point is its not going to happen all the time unless you live at the press and the range.
What I look for in a load deer and varmint killing accuracy. Accuracy first and velocity second.
Flip

Tolkachi Robotnik
April 29, 2013, 08:05 PM
The best accuracy usually comes from powders that have a wide range of charge, but are close to filling the area of the the cartridge available.

True any variable changed can change point of impact, the one that surprises me most is brass. You will do better with same headstamp, same grain weight, same treatment to all the brass. If you start to find an outlier consistent with a set of say five brass pieces, you will be able to remove that from a set and discover it is due to an odd piece of brass. That piece of brass has different volume or thickness compared to the others.

For different caliber cartridges, there are many common and popular powders. If you deal only with those often found by others to be worthy for that cartridge the number of permutations come down markedly.

When you find one that works extremely well, pay attention to the stated or chronograph speed. This speed often will work well with other powders, and it is the first place to home in on if you must change powders and had a favorite. This is same somewhat with bullets as well. The fastest possible is rarely the most accurate in my experience, it usually comes about when efficient and regular straightforward powder burning is accomplished, less overblow as bullets come out barrel, more uniformity.

If you enjoyed reading about "Change 1 variable, changes them all?" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!