What is the proper neck tension for a magnum rifle?

S

SteveS

Guest
Having a problem with a 300 WSM and neck tension.

Just got back from a deer hunt where I had a problem with recoil related bullet pullout. All loads had cycled successfully in this gun before. After my first shot, the second went in kind of tight. While I was watching to see if the deer was actually down or would reappear I double checked to make sure I had actually chambered a cartridge after the first shot (sometimes the buck fever gets to you). When I opened the bolt, which was difficult, I ended up pulling the bullet from the cartridge because it had jammed into the lands. Good thing the deer was down because all I had at that moment was a heavy metal stick to throw at it.

When I got back home I started double checking things and discovered that the sizer button on my Redding dies is only .0015 under bullet diameter, .3065 vs. .308. This seems to be very light tension for a hard kicking round. I checked all my loading books and the only reference to neck tension was for target shooting and it recommended 1 to 2 thou of tension. I plan on contact Redding tomorrow to see if I possibly have the wrong button.

What is the proper tension for a magnum rifle, or any hunting round for that matter?

Would I be better off to crimp? I was thinking of maybe trying the Lee factory crimp die.

Thanks

Steve
 
You have a short neck and a heavy bullet and a lot of recoil so I would use a crimp. The expander ball may only be .0015" less than bullet diameter, but the neck springs back some after the expander ball passes through. What is the OD of a loaded round neck compared to a sized case neck? What is the case neck diameter when you size a case with the expander removed from the die? How many times have you reloaded your brass? - nhk
 
Any high recoil Rifle that has to feed from a magazine will usually have to take advantage of a crimp in order to keep the bullets from moving under recoil. The truth is you can only achieve so much grip with neck tension, you deed the positive stop that a crimp furnishes. This also holds true for big magnum handguns.
 
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The Lee crimp die will solve your problem. It is the only die I know of that you can crimp at any length without using a cannelure on the bullet.
 
Most factory ammo with large capacity is crimped, especially with a box magazine, such as the .284 in a Model 88 or 100.... for that reason.
 
Steve, like others have said crimping is a good way to go. FWIW, I put together a 300WSM hunting rig for a pal (pic below) and am using a Redding Type S f.l. die. A neck bushing .006 under what the seated bullet measures hasn't allowed the bullets to move under recoil, yet. This is with the Nosler Accubond 180's. The standard Redding f.l. die I have sizes the neck .008 under the seated dimension.

Good shootin'. -Al

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Guys,

Thanks for the advice.

I went back and measured some loaded and some resized cases and got a difference of about .0015 to .002. (.335 vs. .3365). Then I pulled the button from the die and ran the sized cases thru again. If anything they only shrank maybe .0005. Note that the half thou differences are estimates as I only have a standard micrometer. This is with brand new Federal cases.

So I thinks it's the Lee crimp die for me.

Al, your Redding die is sure a lot different from mine, either that or your necks are a lot thicker. From what I measured my necks are about .014.

Steve
 
Die

SteveS said:
I went back and measured some loaded and some resized cases and got a difference of about .0015 to .002. (.335 vs. .3365). Then I pulled the button from the die and ran the sized cases thru again. If anything they only shrank maybe .0005. Note that the half thou differences are estimates as I only have a standard micrometer. This is with brand new Federal cases.
Click to expand...

That seems unusual. Are you using a standard full length die or a full length die with a neck bushing? Like Al said, "The standard Redding f.l. die I have sizes the neck .008 under the seated dimension." - nhk
 
Do you have a type S die which uses bushings??? if so you must remove the expander ball so that the ammount of "squeeze" is determined by the bushing,,,NOT the expander!!....Roger
 
I'm using a standard FL die from Redding, no neck bushings. It seems unusual to me as well. I'll send a note to Redding today and see what they have to say.

Steve
 
Al, I'm estimating .014 for my brass simply because the loaded rounds are .028 or so over the bullet diameter. What do your loaded rounds measure?

Steve
 
After over 60 years of reloading for competition and hunting, I would consider it foolish to not crimp heavy-recoil loadings.
 
crimping with the old style crimp and seat die is not a good thing unless all the brass has been trimmed to length..every time.

lee has over come this issue with thier factory crimp dies.....it is quite possible to produce crimped and accurate ammo today.


it works...the results are good...
so has the one naysayer, actully done any crimping with the lee tool..any current testing ,or just expousing old wifes tales...???

do i crimp my br rounds...no, do i crimp some other rifle rounds yes....can i hit the broad side of a barn door with that ammo...yes....typically still around 1 moa.
some one that has actually been there done that....

my ar's( not in the recoil level of a short mag hunting rifle) only require 2-3 to prevent 175's from moving(ar10) and about the same in the 223 depending on bullet weight.

mike in co
 
another approach.....a spacer in the mag to prevent movement...i personally find it strange that mag length ammo jammed the lands...i wish i had that problem. proper neck tension or crimp should resolve the issue,
mike in co
 
Crimp! Crimp! Crimp! There I said the "bad" word. I recently turned down a Hart barrel from a Remington 40X for a Savage, set back the chamber, re-crowned the muzzle and intalled a muzzle brake. The 18.5" barrel was a 1:14 twist and my .223 Rem reamer was for 55-69 gr bullets (1:9 twist) so when I loaded 40 gr Nosler Ballistic tips there was only .060" of the bearing surface in the case neck with .010" jump so I CRIMPED them (with Lee). I went to the range and sat down beside a benchrest 6 PPC with my varmint rifle on a bipod and we both shot groups in the .2's. I even had a group in the .1s. I hate to think what I could have shot if I hadn't CRIMPED them. - nhk
 
Guys, thanks for the help. As with any issue there are varying opinions.

I'm interested more in hunting accuracy (I strive for at least 1 MOA) than BR levels of accuracy. I believe I will start with the Lee crimp die and see what happens. It's only about $11 and will only require me to keep the trim length fairly close to get consistent crimp results. If the results are not satisfactory I can then decide if I want to shell out the extra bucks for a bushing type sizer die and the extra issues (like neck turning) that may come with that.

I'll post my results when I get a chance to test them out.

Steve
 
Steve....with a type S die neck turning is NOT required,,,you just have to use a bushing .003 ,+/- a lil' , smaller than a loaded round ND...Roger
 
Neck size

SteveS said:
I believe I will start with the Lee crimp die and see what happens. It's only about $11 and will only require me to keep the trim length fairly close to get consistent crimp results.
Click to expand...

That's the cheapest and least trouble to do. You might take one case and anneal it, then size it without the expander button and see if what the neck size is compared to the other sized necks. I still think it's unusual that a full length die is doing so little to the neck size. A case with a .014" neck wall thickness should still get sized more than what you are seeing. Most full length dies over work the neck at least .004-.006". - nhk
 
lol his mind is made up.....his own line..you cannot teach old dogs new tricks( like lee factory crimp dies)
charles e...
we have agreed that it is unlikely we will agree on all things.
but...
since i do own and shoot br rifles, and specifically did what he asked me to do to prove it..i shot in a registered ibs match...
how about deleting every post of his where he claims i am not a br shooter ?

and then we can progress from there....like his lack of data on this subject...

your buddy
mike in co
 
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