nosler brass & 20vt has me stumped

[fishnbob]

I cant seem to get this nosler brass to shoot. I am hoping you guys ill have some suggesttions.
First, some history. I posted here a while back with forming steps I use to make military brass into 20vt brass. It still shoots lights out. I consistantly get 1/4 inch 5 shot groups and sometimes a little smaller yet. So it is not the gun or scope.

Now the nosler brass issues.
It is nosler221 fireball brass. I ran it through a redding body die, then redding neck sized with 226 bushing. Third, I used a K&M expander and cleaned the necks up about 90%. Fourth, I annealed the necks and ran them back through the redding neck die.

Now the problem begins. These suckers wont shoot beteer then 1-2 inch groups. I tried the same pet load as my formed military brass which is 18gr 4198. I have tried 17gr-18.4 in .2gr increments with same bullet and seating depth. I havent had a chance to chrono them yet to compare to the military brass which is at 3580 with the 18gr h4198.

I dont have a concentricity gauge, so i have not checked that.

Any suggestions would be appreciated. I had high hopes for this brass and made up 500 of them. Good thing I made 800 of the military brass I will at least have that for my pd trip in June.

If anyone with a 20vt is interested i will send you 10 or so to look at and try and see if you can figure it out.
One last thing, I havent tried loading any after they have been fire formed.
Thanks Bob

One other thing I forgot is the nosler case length is about. 010 shorter then the trim lengthof my military brass.

[Rick in Oregon]

One last thing, I havent tried loading any after they have been fire formed

Bob, the first thing I'd do is load up your pet load in the fireformed brass and try that, as fireformed brass from your chamber should be the most "accurate" brass you could use. I'm shooting a Cooper 20VT and using Nosler brass. I have no trouble shooting one-hole bugholes with the stuff, so I'm guessing it's not the brass.

My TIR using this brass after fireforming with a bullet seated is right on .001", as I just loaded up a batch yesterday and checked the TIR prior to boxing 'em up for an upcoming rat shoot. If you expect dinky groups, a concentricity guage is a good thing to have on the bench.

Try your pet load again with your fireformed brass, and you should see an improvement.

[fishnbob]

It might not be the brass but I was worried it might be something I did to it because I have no trouble shooting the small groups withfire forming loads from the military stuff.
Thanks Bob

[wirelessguy2005]

Bob,

When I am forming the Nosler 221 for my 20 SCC i do so in 2 steps. I run them thru my Whidden 20 SCC FL bushing die with a .241 bushing and then again with a .230 bushing. After this i prime, charge, and seat the bullet. I don't believe you need to anneal the Nosler 221 brass when only stepping it down to 20 caliber. In the 20 SCC with fireform loads i am getting groups well under 1/2" if i do my part.

As Rick noted i would reload the formed cases and try them again, most likely you will see better accuracy the second time around.


Also out of curiosity what does the neck on your 20 VT chamber measure?

Brad

[acloco]

What is neck thickness prior to necking down?

What is neck thickness AFTER necking down?


IMHO, I would neck turn BEFORE necking down. Otherwise, you will end up with "donuts" at the neck/shoulder junction.

As RIO suggested, check TIR. Also check how much neck tension on a necked down, but unfired piece of brass. Suspect you may have neck tension and/or a donut that is coming into play.

As wirelessguy and RIO suggested, definitely shoot a couple of fireformed rounds as well.

Please let us know what/how you proceed.

[bow shot]

Aye... I've been bitten by the doughnut louse in times past, has caused sorrows. Beware!

I've used the K&M cutter for that, it works extremely well. Just be sure to start it into the neck turning CCW, then you can go ahead and turn CW, it will be smooth sailing. Otherwise, its not fun at all.

That said, I just neck turn cuz I can and I like concentric ammo even though my rifles probably can't tell any difference.

[RAMOS]

+1 on all of the above.

In particular, if you did a 90% clean-up on the necks, I would wonder if you have enough neck tension after going through a .226 bushing. How thick are they? Also, make sure the inside of the necks are squeaky clean after annealing.

[fishnbob]

Been real busy and havent had time to play. As soon as I get a chance I will try some of your suggestions and let you know how it turns out. Hanks

[bow shot]

man, that is soooo understood, lol!!