If neck tension is to tight will this affect accuracy on 284??

[Raptor]

Guys, my acccuracy on my 284 has become very inconsistant. I tried a different scope and it does about the same thing. One time it will shoot .5 MOA or under and the next time, same load, same time, same contitions it will be .7 or worse.

I have shot it at 100 to 600 load testing with the same results. The only thing I noticed the other day was the damn neck tension is "TIGHT"!!!!

I have a set of Hornady dies because they didn't make the Forrester dies when I bought mine. I have a new one on order from Forrester but it won't be in for several weeks.

I discovered the tight neck tension the other day when I went to pull a bullet and could not get it to come out of the case. I figured it out and I have around .008 neck tension on my loads. I believe its gotten tighter with repeated reloads on the brass.

I am now thinking this may be my problem with inconsistant accuracy. Any thoughts??? Thanks guys!!!

 

[DennisH]

I personally don't run as much neck tension as you do. I do make sure all my loads are consistant, even neck tension.

I am sure several will chime in. I am interested in the answer to your question as well.

 

[Steve Blair]

That is a lot of neck tension. I use .002" in two match rifles, .284 Win and .284 Shehane. Aren't you seeing a bullet tip ring from the seating stem?

 

[bighorn06]

Are you annealing your brass? Mike

 

[wvuredneck09]

I second bighorns question. Sounds like the die is over working the brass and if you're not annealing you now have to much tension and hardened case necks, concentricity is likely poor and the jacket of the bullet may be getting damaged seating. If the necks aren't uniform the hardened neck will kick the bullet toward the thin side. Just a theory but I'd get a better die, no need for more than .003 neck tension even in a semi-auto for a 284, not an enormous amount of recoil.

 

[Raptor]

I have a new die on order as we speak but it won't be here for several weeks. I "Don't" anneal my brass I am not set up for it. There is no marks on the brass that I can see but then I am using the AMAX so the plastic tip may be hideing it. I also neck turn all my brass to keep the necks the same thickness. Thanks for the thoughts guys!

 

[bighorn06]

I absolutely guarantee you will see a difference if you anneal your brass. All you need is a drill with a deep socket with an adapter and a propane torch. A semi dark room, just enough light to see what you are doing. Direct the flame on the shoulder of the case while slowly turning with the drill until the neck turns a very dull red and dump the case on a thick towel to cool. The shoulder should protrude about 5/8 " above the end of the socket. It doesn't get any easier than this. I also recommend a bushing no smaller than .003 less than the neck of a loaded case. With the cases annealed you can vary 1,2,or 3 thous, of neck tension and select what you want. Mike

 

[Preacher]

The ring from seating will be below the tip on the bullet, and .008 tension should leave a noticeable mark just below the tip..

 

[CaptainMal]

Sounds like you have a "sweet" rifle. Not sure if it's a target, hunting or competition rifle. Do know it shoots way better than most rifles I have and most all rifles I have ever seen.

Shooting real .5 - .7 MOA groups takes some special skills and equipment not easily found. I think most people write about their rifles shooting well but in reality at the range, they come off shooting stupid.

If you shoot that good I think I'm gonna mess up my seating tension and maybe do better.

Nice shooting.

 

[mikecr]

You turn your necks, and STILL oversize +6thou, AFTER spring back/expansion?
How much chamber clearance for the necks?
How many times have you reloaded these cases?
Are your bullets seating to exactly the same OgvOAL, given huge seating forces?

You need to go back to your plan.
What was it?

 

[Raptor]

Thanks for the replys guys!! I just "Clean" the necks when I turn them taking about 2/3s to 3/4s of the case neck off so I have a pretty even neck thickness.

Captainmal,
The rifle is a tactical/target style rifle. It has a Light varmint Kreiger barrel on it with a 4.5x14 Leupold scope. I am having trouble with it right now but it was a "Hammer" When doing load testing at 400yds it was shooting 5 shot groups in the 1.4 to 1.7" range. I even shot a 1.4" group at 600yds but then it was a perfect evening with no wind and only did it once but it was nice to go home with 3 groups at 400 and one at 600yds all under .5 MOA!!

This past saturday I shot at 300yds because the wind was suppose to start blowing and the first group was 1.3" @ 300yds with 4 in 1" the second group was 2.5"s and a pattern not a group. The wind was starting to come up but I don't think it was that strong. SOooo you can see my frustration.

As far as my shooting ability, from what I read on here, I couldn't even carry ammo for some of these guys, the way them and their guns shoot!! Hell I may even be the guns problem!!!!

 

[Switchbarrel]

Thanks for the replys guys!! I just "Clean" the necks when I turn them taking about 2/3s to 3/4s of the case neck off so I have a pretty even neck thickness.

In addition to some things already mentioned, if there's any of the "dreaded donut" resulting from neck turning, that won't help seating force/neck tension/load consistency matters either.

-Rick

 

[Joe O]

http://www.customreloadingtools.com/crt_006.htm

Here is a simple tool that works great for annealing,from Custom Reloading Tools.

 

[Shynloco]

Raptor,
I've seen all sorts of suggestions by knowledgeable shooters regarding "Neck Tension" and how to keep it consistent. I claim no expertise per se, but have found over the years that it is a must to maintain consistent accuracy. Having said that, I'm one of those people who HATES annealing, doesn't have the knack to do it or the funds available to purchase one of those neat new fancy annealing machines. Besides I don't compete shoot strictly for enjoyment and those .200 - .300 groups are just fine with me. But here's what I do to monitor and maintain neck tension and consistency.

First off, you never did say what brass you are using. I use strictly Lapua because it's the most consistent coming out of the shoot. Secondly, my belief is that turning brass is ok if you want to do it lightly to make sure it's as near perfect as possible. On the other hand, unless you have a "custom" chamber and have the reamer that cut it so you can measure it to the .001, you are wasting your time and effort in turning your brass. I've tried both ways and have found that cutting neck can create back pressure issues/blowback unless you have a "tight" chamber as evidenced by carbon deposits on the necks of your casings. That to me equates with another variable in terms of inconsistent pressures when the bullet is released upon firing. And let me say that when I was new to the 6mmbr desire for ultimate accuracy, my teacher cut all my necks for a Savage 6mmbr Model 12 Benchrest Model rifle that I do not regard as "custom" by any stretch of the imagination. But she sure does still shoot nicely after two years and 2000 rounds down her tube. And those loads were using about 90% Vhita Vuori N133 which is a very clean burning powder. And that brass, even after 48 reloading was never annealed and the groups were consistently tight. Finally, on loading #49, those 35 pieces of Lapua brass with turned necks finally gave up the ghost and lost their elasticity and like I said earlier, I don't anneal because I'm rotten at it, not to mention the brass served had served me well. BTW, I follow the same reloading regiment in my 6.5 as well as the other calibers as well.

Bottom line of all that blabbering, NEck Tension IMHO will absolutely affect your consistency and accuracy. One last thing, I have removed the expander balls in ever die I own and use the Sinclair Mandrel Die with the Stainless Steel expander mandrels in all my calibers I reload for. The result I have obtained is more consistent neck tension, more consistent concentricity in runout and ultimately nice tight groups when I do my part. Good luck and have fun with that .284.

 

[Cakes]

I run a straight 284 w/ a .315 neck. Turn all my Lapua brass for approx. 4 thou total clearance which has given me very good results. My other 284 enjoys about 6-7 thou clearance. I anneal after every 3 firings and use about half thou of neck tension and push the shoulder back about half a thou. when sizing. A person does what gives them the best warm/fuzzy feeling and that process works for me. I have accidentally used the wrong size bushing which gave me about 2 thou tension and other than more seating force required, there was no change in accuracy at 600/1000. Neck tension starts getting excessive and IMO you will see changes in accuracy. Consistency is key and its much easier to accomplish with light neck tension. This light of neck tension will NOT work on a hunting gun as there is a good chance you'll leave the bullet in the chamber if you extract a loaded round. +1 on ditching the expander ball, you will see a difference without it. Good Luck, Eric in DL

 

[Raptor]

Thanks again for the new replys. I am using Winchester brass because I got a good deal on some when I started my project. It seems to be very consistant and has shot well in the past.

I did anneal the brass and even though I got my new Forrester die it still has a tad more neck tension than I wanted. With the new die its right at .0045 so I ordered an oversized button for it.

To be on the safe side I also sent the scope back to Leupold to be checked out. I will keep you guys posted when I get everything back and this damn weather cools down and the wind quits blowing 25+mph every damn day!!