What would cause this

[Dan877]

I finally had a chance to begin working on loads for my Howa 1500 Heavy Barrel in 204. The only powders I had on hand suitable for the 204 was Varget and Accurate 2230, so I loaded 18 rounds of each in a starting load.

At the range I started with the Varget loads, 27g Varget, 34g Dogtown bullets, Win. cases, CCI primers. For 6 three shot 100 yard groups I got:

Group 1: 1/2"
Group 2: 1/4" with two shots overlapping
Group 3: 1-1/2"
Group 4: 3/8" with two shots almost through one hole
Group 5: 1/4" with two shots almost through one hole
Group 6: 3/8" with two shots overlapping

Next was the 2230, 24g, same bullet, case and primer as above. I got:

Group 1: 3/4"
Group 2: 1-1/2"
Group 3: 3/4"
Group 4: 3/4"
Group 5: 1/2"
Group 6: 3/4"

The weather was cold, drizzling rain, heavy overcast, but with only a slight breeze. I'm stumped what might have caused the two wild groups. The first time I thought "uh-oh, the scope must have come loose," but the subsequent groups seem to rule that out. So anyone have any ideas?

[OldTurtle]

I load with W-748 and Ramshot X-Terminator and get somewhat the same type of spreads when I'm experimenting with charges and seating depths.

I've read several articles on the harmonic vibration nodes that are in every barrel and believe that is the cause. I don't challenge it too much, just identify the loads my barrels like and stick with them.

Fortunately, both of my .204s like the same load of W-748.

I would try working up some 5 round sets that are 0.1gr on either side of the charges you tried, as long as it isn't near max. and see if a different velocity doesn't look a little better or at least more consistent.

I suggest 5 round loads as, just like your groups, you have a couple that the rounds are touching with a flyer. Is the flyer the fault of the shooter or the load?... With 5 shots you get a more definite idea.

When I'm trying to find a good load, I will track back from the max listed load in increments of 0.2gr for five different loads and give them a try, with the same seating depth, as well as other factors.

If I get one that looks really good, then I'll set up 10 of that one and 5 of the ones at the 0.1gr on either side of the good group and see if they will, maybe come in a little better.

[WrzWaldo]

Dan,

Were all 6 groups with each powder at the same charge 27g and 24g respectively?

[Lee C.]

Dan, First off i don't think your shooting or scope has any thing to do with your groups. As if you look at your 2230 powder test you had 4 3/4 size groups out of 6. When i look for a powder weight for a bullet. I do it the same way Oldturtle dose he's to fine the very best charge you can. Was your test with the varget powder out of a clean barrel? Did you clean the barrel between the varget powder and the 2230 test ? After you fine your best powder weight play with your seating depth. That's got alot to do with your group size also. Whats the count of rounds shoot through the gun so fare ? There are alot of things to look at here. If you could give us any more info it might help.

[jo191145]

I would chalk it up to my old Nemesis and favorite excuse. Changing Bore Condition.

Nonetheless your Howa seems to be a shooter. Those are some pretty good results with the Dogtowns. I never really tried developing a load for them myself. You might want to try some 35 Bergers in the future.

Hodgen states 28.0gns of Varget is the starting charge for 35 grainers.

[Glen]

Perhaps the 2 bigger groups were shot with a hot barrel as opposed to a warm one. I read it as the 1st 18rds were identical with Varget & the 2nd 18rds were also identical except with the 2230. Either way the overall average is very good. The front bag could have been placed in a different spot on the forearam as well giving a different recoil pattern.

JMO

[bushymonster]

Personally I think that is fairly good for Dogtown bullets. If you upgrade to a better bullet, like from lower grade to higher. Start with Hornady. I have great luck with them. Then you have a tie (in my opinion) between SIerra Blitzking and Bergers. I don't repeat don't like Barnes but a good one I left out is Nosler, they are a great bullet. This is just me but Dogtown are not consistent enough for me. You get what you pay for. Nosler has some great overun deals for 500 to 1000 at a time, not seconds either. Check them out. This is just my 2 cents.
Bushy