I am trying to get one hole groups with a custom gun I had built and chambered in a 300RUM. Best I can do is .9 MOA consistently. So I decided to try neck turning. I have a sinclair kit with expander die. I FL these cartidges and check for consentricity, and everything is within .002" or better at the necks. 1st problem is my expander ball on my RCBS dies are not large enough. It is .306". I need it to be .307" to fit my neck turning mandrel. So I have to run all of them thru the expander. This was tough. I lubed well with imperial wax. I even stuck the case mouth in the lube. Sometimes would pull out the expander mandel out of the body. I then neck turn all 20 cases. I check again for consentricity. Either the expander ball or the neck turning itself, knocked the necks out.

I had .004 max run out on the necks. Kinda defeats my neck turning.

So no have to run them thru a FL again.

I know vapordog, your saying, told you so that neck turning is a waste. But hey, its fun trying. I think it maybe better to buy brass in bulk and go thru it with a neck guage and pick out the pieces with good necks instead of making the brass good.

I think experimenting with neck turning or whatever can be a lot of fun. I did it for a while too, but I haven't bothered with it lately. I now pretty much use nothing but Norma, Lapua or RWS brass. The necks of these tend to be pretty consistent anyway. I will measure the necks when I first buy a batch of brass. If the neck is lopsided, then it's probable the entire case is too.

The one piece of reloading equipment that has probably aided accuracy more than any other for me is the Lee collet neck die. It has three advantages basically. First, it makes very straight ammo. Second, it requires no case lube and third, it works the neck less than traditional dies with expander balls. Of course, a good seater is essential to concentricity too. I like the Redding Competition seater best followed by the Forster benchrest seater.

I appreciate the Lee myself. Doesn't knock the shoulders back or up. I still don't think they make one for a 300RUM however.

Just talked to a guy at sinclair, where I bought the stuff. He said for a big boomer like this, only neck size the virgin brass, fireform, do your shooting on the 2nd firing and thats it.

As close as I recall this is a quote from Layne Simpson....."Such finness things as turning necks (etc.) are only valuable if your gun and cartridges already are shooting 1/2" groups at 100 yards.

I too have turned necks.....deburred flash holes, uniformed primer pockets and have never found those activities to hurt anything......but with frustration I could also never find an advantage as well.

Try this test.....get 25 virgin brass and fire them once all the same and then reload them all identically except for ten of them having the necks turned. Then proceed to get two ten shot groups at the range and observe any differences. A good understanding of statistics is critical to actually saying that there is a real difference....the more often this test is done the more reliable the test is.....I'm all for testing.....that's one of the benefits of reloading. The trick is to not be fooled by the testing.....and that's no easy task.

I do enjoy reading the results of others doing the same testing....almost exclusively they share the same findings as I've had.

Well, I have done a simular test. I used the exact same pet load with 165gr sierra gamekings and 45gr of Varget. I shot 20 shots with runout less than .003, and shot 20, that were ~.007.

There was a real difference. Average group size of the ones with low runout was 1.2" at 100 yards. Average for the ones with large runout was 1.6". Also noted the flyers was causing the higher number.

Is that worth it? Probably not. But I continue to cull thru the brass.

Your neck turner might come in real handy if you ever have a custom rifle built in a wildcat cartridge thay requires necking down the parent cratridge.

There you go, I just gave you a good reason to build yourself a 6.5x.284

Very true.

bigcountry,

I'm sure you have tried several powders but I'm wondering if you just haven't found the one that rifle likes. What powders have you tried with this caliber? I'm wondering if the group sizes have more to do with that than run out? Just a thought

Believe me, I have tried them all from speed of IMR4350 and up. This is my third one. The others are good hunters. I just had high hopes of this one as a competition gun.