Help fixing a flier??

[albertakid]

Okay here is the deal I have been trying to mess with some loads for my 308 and this is what I have happening I am shooting 46 grains of varget with winchester brass and 168 grain seirra match king bullets and cci bench rest primers and I think I am getting a flier I have four rounds inside of 6/10's of an inch and one out making it a 1" group. I have free floated the barrell and shot three fouling rounds before grouping will glass bedding help and can i exceed the max load, by a little bit to close this up it (I see no evidence of exesive pressure with 46 gains) maybe it is human error as well?

Any ideas??

Here is a pic of the group the flier was the second shot of the five and the fifth out of a clean barrell

Jordan

 

[steve4102]

Can you exceed max? Well, that depends on what you call max. You see, load data is only a guideline and not a recipe. What is safe in one rifle or test barrel may or may not be safe in another. Only you and your rifle can tell you what is "Max" in your rifle.
According to Sierra #5 168gr MatchKing/Varget has a max of 43.5gr. Hodgdon has 46gr Max and Lyman 48 has 45.7gr as Max. Which one would you consider max in your rifle?

As for the flier there could be any number of causes. If you are confident that your rifle and scope are sound, I would try adjusting seating depth, check for excessive run-out, switch to a different primer, adjust powder charge in .02gr increments and maybe give the bore a good cleaning with one of the foaming bore cleaners. What are you using for a rest? I would also have someone else shoot this rifle, could be the shooter also.

 

[AJ Peacock]

What is the orientation of the plate? Is the 1 on the bottom of the plate, the bottom when you had it hung as a target?

How cold was it while you were shooting, I found recently and confirmed with others on this board, that CCI-BR2's aren't hot enough for Varget in cold weather. I was getting the same groups from my 300WSM until I started keeping my ammo warmer. (it was around 20F here).

Also, left to right dispersion can be direct result of too much/not enough/inconsistent pressure on the butt of the rifle.

HTH,
AJ

 

[albertakid]

thanks

I was shooting in about 25 degree weather the pie plate was set so the one was on the bottom at 6 o'clock

Is there another primer i should be using??

I consider 46 grains max as I am using the hodgon manual

as far as seating depth which way should I go??

I was laying prone and using sandbags in the rear and a large bag in the front rest could've been a little better

Any suggestions are helpful thanks

 

[AJ Peacock]

Even though you aren't seeing pressure signs at 25F, I'd expect some to show up if you shot that load in 90F weather. The CCI-BR2 is a great primer, one of the reasons it's so good is that its mild. Mild primers and cold weather don't mix well. You could work up a load with another primer for cold weather or keep the cartridges a little warmer.

First thing I'd do is simply put a handwarmer (one of those disposable kind) in the ammo box so it just breaks the chill.

Second thing I'd do (seeing the group is horizontally strung), I'd make sure your shoulder and cheek pressure are very consistent and shoot another couple groups.

As far as other primers, This link has a nice list of relative primer strengths.

Primer Testing Reference

If you can find a 100 Remington 9 1/2 Large Rifle primers (not the magnums) they are a little bit hotter than the CCI-BR2's, but nothing like the magnum primers. Make sure to work up your load from well below maximum.

Hope that helped,
AJ

 

[Buffalobob]

While you are at it, I would roundfile the 168s and make the move to the 175s. The downrange ballistics near 1000 yards are better even though it starts out a little slower.

 

[Jim Oliver]

I would suggest trying IMR 4895--works better for me than Varget.

As usual---YMMV.

Jim