Hi again!
Trying not to be a pest but I have some questions.

I'm developing an accuracy load for my Tikka T3 Varminter (Stainless/Synthetic bull barrel) in .223 Rem. for long-ish range shooting. I'm starting with 69gr. Sierra Matchking HPBT bullets, because they are widely available locally at a fairly decent price... and I already have several boxes of them. I've decided to focus in using Varget powder, because of recommendations from this forum (and also having a few pounds of it around as well!).

Starting loads were 3 cartridges each of 23.0, 24.0, 25.0, and 26.0 grains of Varget, with the bullets seated 0.035" off the lands (I wanted to seat them closer, but the magazine wasn't long enough!). Case prep was meticulous, and case weights and runout were carefully measured for case segregation purposes. The resulting group sizes showed that the 24.0 grain load had the tightest group (0.5" at 100 yds.) with the rest of the loads ranging from 0.7" to 1.0" - so I decided to do a little more development around the 24.0 grain charge weight.

I loaded up 6 more cartridges of the 24.0 grain charge, along with 3 cartridges of a 23.8 grain charge and 3 cartridges of 24.2 grain weight to see if there was some charge-weight "margin" on both sides of the load (which should also theoretically translate into more stable temperature-extremes and differing case-volumes performance as well...). The results of these loads were (all at 100 yds.):

23.8 grain load: 0.45"
24.0 grain load: 0.5", 0.2" (Two 3-Shot Groups)
24.2 grain load: 0.25"

My question is this: Should I just "settle" on this excellent load (24.0 grains Varget) which is consistently sub-1/2MOA with margin on each side of the load map, or should I do more exploration in both directions in terms of powder charge? Should I attempt going higher than the 26.0 grain initial loads (I could go as high as 26.7 grains, according to Sierra)? When should I stop and say "good enough"? What would you do after achieveing these results?

Thanks for reading!

First, congratulations on some excellent accuracy.

Unless you are an experienced bench shooter and shooting under controlled conditions at an indoor range, the difference in a .5" group and a .25" group is less than that caused by wind differences and introduced human error. In other words, don't assume that the load which gave you a .25" is actually superior to one that gave you a .50" group. It takes a lot of shooting under controlled conditions to tell much about such small changes in load weight. Besides, a difference of only .2 grains is within the variance of many loads and it is rare for such a small difference to be detectable from shot to shot.

Also, three shot groups are good for trial-and-error searches for promising loads, but you really need to shoot several 5-shot groups with each sample load to learn something difinitive about its potential.

I agree with stonecreek. You must shoot 5 shot groups in order to have confidence in your chosen load.
Also, try WW748!
Peter.

Stonecreek (and Peter),
First off - THANK YOU for the input. Now I'll address each point.

I'm not a benchrest shooter, but I'm very experienced at shooting for accuracy from a bench - I've got over 25 years of reloading and accurate target shooting experience behind me. I know how to read the wind and minimize it's effect on my results, and I almost always choose calm days to test my loads. I have good breathing, holding, and trigger control skills - which I think my results show somewhat!

The reason for the 0.2 grain increase and decreased charges was NOT to try and find a more accurate load, but rather to see if there was some "margin" around the 24.0 grain load that I'd already determined was an accurate load. Sometimes you work up a load and get an accurate result, but only a SMALL change in powder charge, temperature, or case volume will make the group widen out again. I wanted to see if there was any "buffer room" on both sides of the 24.0 grain load - which my results seem to indicate there is.

My final thoughts on what you wrote are this: I've got a proven load now (24.0 grains Varget) that has CONSISTENTLY come in sub-1/2MOA with 3 separate 3-shot groups. I don't know if shooting a few 5-shot groups would tell me much more... I know when I overlay my three targets (since I haven't made any scope setting changes) the 3 groups STILL make a sub-1/2MOA 9-shot group, so I'm pretty certain I have a winning load.

I guess my main question still stands - how much is "good enough", and when would you start developing for a different bullet and say that this load is fine for its intended purpose?

Gaillo, some responses:
1. I still do not believe that you have a proven load by which I mean "I" would not draw that conclusion. If you choose to, thats fine, but, statistically, your confidence factor is low (in my opinion). Bear in mind that when the NRA tests rifles in the American Rifleman, they shoot 5 10 shot groups before they conclude on the acccuracy of that rifle.
For your other points, again, it depends on what your load is for. In my case I was developing loads for F class which at my club, is shot at reduced targets at 200 yards. Therefore I shot groups at 200 yards (and not 3 shot groups either, but then you have heard that before!). I shot 10 shot groups. Amazing that these groups are bigger than my 5 shot groups.
Now, I am developing loads for 600 yards. I have my 69 grain load (which as I mentioned uses 748 rather than Varget), but, just in case I need a better BC, I am developing a load using 77 grain bullets. These may not give as good a group at 100 yards as my 69 grain load, BUT, the practical effect at 600 yards may be better. Of course, you know "how to read the wind", so that may not be factor for you, but it is for me. I have only shot up to 900 yards so I am no expert.
Your search for a stable load (ie. small changes don't make much difference) is perfectly sound. After all, that is exactly what the famous Audette method does. In addition, it allows you to throw charges rather than weigh them individually, which, if you are loading up 100 or so, gets to be a pain.
Peter.

Myself I try to decide what is good enough for me before I start to load for a specific gun and bullet if possible. You have to decide what your goal is and then quit when you are happy with the load. If you just want to see what the gun can shoot you may be busy for a very long time. This is ok also if it makes you happy. Myself I set a goal of a bullet or 2 and a couple of powders that I think will make my velocity and accuracy goals and then stop when I have met my preset goals. dave

drichi, goods points except that I do not set my goal ahead of time. I just don't know the accuracy potential of that rifle. But, after hearing about other peoples results with the same rifle, plus my own experience with that rifle, I can get a pretty good idea. So, my Savage 110FP in 223 is a good 1/2 MOA shooter out to 200 yards, but, I would certainly not waste my time trying to get my Ruger Ultralight in 257 Roberts to shoot 1/2 MOA. My life is too short and I don't have the money! Having said that, plenty of folks have what Eddie Harren calls "billfold targets". These are single targets that their rifle shot once, and so they keep it in their billfold to show others! So, bottom line is I try to be realistic in my goals. Gaillo looks like he is primarily interested in accuracy. A hunter would want to combine accuracy with a certain velocity envelope.
BTW I have a couple of benchrest rifles where I would NOT be satisfied with 1/2 MOA
Just FWIW, Peter.

At 24 grains of Varget you are at the minimum load recommended by Hodgdons and are giving up 300 fps of the 223's potential.

I would consider it an accurate load but a less than functional one unless you are just going to punch holes in paper at 100 yards.

quote:

Originally posted by Fjold:
At 24 grains of Varget you are at the minimum load recommended by Hodgdons and are giving up 300 fps of the 223's potential.

I would consider it an accurate load but a less than functional one unless you are just going to punch holes in paper at 100 yards.

Hmmm... interesting. Sierra lists 24.0 grains as near the upper-middle end of the loading range, with 26.7 grains being the maximum load. Could Hodgdon's data be for a different bullet? I'm getting an average of 2920 FPS with my 24.0 grain loads.

I know everyone talks about 5 and 10 shot groups as being necessary. 3 shot groups are just fine for me. I shoot to hunt. I do not shoot to be a paper puncher. I do think it is a hoot when I shoot a great group, but my goal is always preparing my firearm for a hunt.

IMO you have found a good load, but as other posters have said, it is a light load?? I try to get the most performance I can, but still get acceptable accuracy(for the hunt).

Also for my varmint rigs I am more concerned about accuracy at 200 or 300 yards. If you are happy at 100 then it is definitely time to step up the distance. Tom.

Give 24gr of Varget loads at greater distances. See how it groups at 300 to 400 yards.
Sounds like your having a good time.

quote:

I know everyone talks about 5 and 10 shot groups as being necessary. 3 shot groups are just fine for me.

I've lately been playing with taking some targets out in the woods, and setting them up at 100 to 150 yds thru wooded areas between me and the target.. clear shots but narrow alleys thru the brush and limbs...

then I shoot single shots at them from various positions and see how many times I hit a 8.5 x 11 sheet of paper with a target on it( ran off the net)...also using various shooting stances.. all off hand..

let me tell you, the results can be both sobering and humbling... it can also build confidence as you see vast improvement, which has been surprisingly quick...

I have done this with the 6.5 x 55, the 223 so far... needless to say the 223 is much more economical for this type of training...

I am also going to try this with my CZ 452, with smaller targets of course at shorter ranges.....

but doing it in the woods environment where we usually hunt also helps tremendously.. especially doing so thru little windows of opportunity thru the brush....

and having an accurate rifle and an accurate load helps...

and then once you get good at it from 100 to 150 yds, stretch that distance out farther...

For hanging targets for those that will probably ask.. I just took a small piece of ply wood big enough to staple two 8.5 x 11 targets on it. and put an I bolt thru the top... using a bungie cord, I hang it from a tree branch or strap the bungie around a tree's trunk and it gives me a stable target platform...

to increase the challenge, just run off smaller targets....