Load development, grouping for accuracy

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.5MOA

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Had a friend doing me up some loads for my Remington .308 Compact Tactical. Loaded up 5 rounds each of some Varget from 44.5-47gr using winchester brass, 210 primers and 168gr sierra BTHP's. All groups were shot off a bench with bipod and rear bag at 100 yards. I have to get a new set of rings, had a different scope on but just put this one on last week and didn't have another set to use yet so it's sitting way too high.

5 shot groups went from .871-1.692" ceneter to center (is this the right way to measure group?). Now 3 of those groups had 1 flyer in each. If I took the flyer off the 3 group sizes that had them then all 6 groups were 0.192-1.504 with only one grouping over 1". Could I assume that the 4 shot groups without flyers are representative of the load or should I reload them all and try again. The 44.5gr of Varget gave me a .871 5 shot group and the .192" 4 shot group.

Thanks in advance.

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Groups look good to me. It just looks like you shot in a different wind conditions with the flyer.

Top group left wind picking up
bottom group either tailwind or headwind with some side wind pickup a letup for the flyer.

Wouldn't mess around with the load yet until you set up some type of wind indicating device and try again.
You should try to shoot at 300 yards. At least your bullet has time to stabilize.
 
I found the 168s liked to be driven around 2625-2650. In my gun that needed 44gr of Varget. I'd suggest you start fine tuning in 0.2 or 0.3 increments from 44 to 45.5 and see what happens at 300y.
 
Thanks guys! I have a few rounds of the 44.5 being loaded right now to try out next week to see how they do. Anyone have any luck with R15 with the 168's?

I'll ask him to do a few from 44-44.5 in smaller increments to see what happens as well.
Thanks again.
 
.5MOA said:
5 shot groups went from .871-1.692" ceneter to center (is this the right way to measure group?). Now 3 of those groups had 1 flyer in each. If I took the flyer off the 3 group sizes that had them then all 6 groups were 0.192-1.504 with only one grouping over 1". Could I assume that the 4 shot groups without flyers are representative of the load or should I reload them all and try again. The 44.5gr of Varget gave me a .871 5 shot group and the .192" 4 shot group.
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We can give ourselves the smallest MOA handle in the world but few of us can shoot to match it. Me included.
 
Before you try to many more loads is your rifle properly bedded and is everything tight.
By the looks of the groups you seem to be a good shot but somehow I feel there is some movement somewhere , is the scope known to be good also.
My guess is bedding if it isn't done.

Another possibility could be the brass if it is not sorted by weight or uneven neck tension could also be bullet seating depth is inconsistent.
 
The rifle is bedded, Gordon Whitman (Blue Mountain Sports) did the work. I don't know about the scope, just bought it (used) here on EE and got it mounted last week.
 
It could be a number of things like I said earlier but you could try a few more loads with a diferent over OAL that may just do it for you , I think 47gr is a little hot though for 168 and varget.
If you play with bullet length star with loading 5 touching the lands 5more 5 thousands shorter and so on until you are about 25 or 30 thous off the lands you will likely find a sweet spot in there.

Imo 46gr of varget would be what load I would use even though your group is wide there is no vertical ,was it windy that day?

I load for 3 308's and they all get there best groups near max pressures with varget.

Bullet length is key to tighten up the groups.
 
I'd roll with the 45gr load, and tinker with seating depth at this point. The 44.5gr and 45.5gr loads hit the same POI, so you know that atmospheric changes won't affect your POI much, if at all. You can find the accuracy you need by playing with seating depth, although the groups look pretty good, as is.
 
Flyers are part of the group, this isn't golf, there are no Mulligans.
SMK bullets are very jump tolerant, but seating depth should all be the same. 47 gr of Varget is a hot (maybe too hot) load for 168's. Go back to your 44.5 gr load and go up and down .2 gr and see if that tightens things up. Also before shooting any groups fire a few fouling shots if your bore is clean.
 
maynard said:
Flyers are part of the group, this isn't golf, there are no Mulligans.
SMK bullets are very jump tolerant, but seating depth should all be the same. 47 gr of Varget is a hot (maybe too hot) load for 168's. Go back to your 44.5 gr load and go up and down .2 gr and see if that tightens things up. Also before shooting any groups fire a few fouling shots if your bore is clean.
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I wasn't suggesting that the group was better than it was:), just pretty new to this load developing thing and didn't kow if I should include them when looking at the accuracy of the load considering how well the others placed.
I'll go back and get some loaded in .2 increments either side of the 44.5 and also adjust the seating depth and see what it does.
Thanks all for the advice.
 
Breaking good shots and being honest with yourself if you shank one will help. If the shot didn't feel right, or you pushed or pulled it that's pilot error and fixable through practice and calling your shots.

If you are shooting in windy conditions look for groups that have very little elevation difference. If you group is a 1/4" high and 3/4" wide on a windy day, chances are it is a good load.

Find the best load, then play with the seating depths another day, to see if you can fine tune it. If you are switching loads and changing seating depths you are just chasing your tail.
 
looking at those groops, I would retry 45 gr at different seating depths, then try changing primers to fine tune it. I find the throat on the remington 700 can be a bit long and seating the bullets out can really improve things. If that works then try increasing the powder charge in 0.1 gr steps.
Mine likes rem 9 1/2 primers with the 168 MK seated to 2.925 OAL @ 2735 FPS.
 
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