Neck Tension

[ofdscooby]

I had a rifle built by a friend its a 7mm rem mag using a Stiller action, Bartline barrel, McMillan stock,Jewell trigger. He used a match reamer so he says and has consistently built tack drivers for other people. Well we found a load that works good but I'm getting some wild ES's of 50 and he suggested neck tension. it hasn't mattered at closer distances but everything falls apart past 725 yards. How do I go about getting the most consistent neck tension. I'm using redding dies on a Hollywood press Retumbo and a 168 Berger's 30 off the lands.

 

[ohiohunter]

Do you turn your necks?

 

[ofdscooby]

No I don't

 

[bkondeff]

You noted a "match" reamer, so does that imply a tight neck?

 

[ofdscooby]

He said its a no turn neck but would prefer I use a higher end brass and suggested Norma. I couldn't get my hands on any and tried some twice fired federal that I maticulosly prepped and a few didn't fit. So how do I get this consistent neck pressure brass, dies, neck turning? I've stepped up my platform and now I need to step up my reloading I guess.
My load right now is 69.5 of Retumbo with a with Win primer and this is with brand new win brass
Prepped by flash hole debur, primer pocket squared up, chamfered/deburred.

 

[MTBULLET]

necks have to be uniformed for best results

 

[ofdscooby]

So from my research that would be to turn the neck then use a bushing die to get the neck right where I need it?

 

[Cuz]

I skim turn the necks, use a sinclair expander and anneal every other firing.

 

[ohiohunter]

A match primer will help too. When you turn the necks you don't have to turn them paper thin, but you do want to get a more uniform thickness without taking off too much.

 

[brentc]

This is common for Retumbo in the 7RM for some folks. The easiest solution is to switch to H1000 for the 168. You'll lose some velocity, but the ES will even out. A well tuned load with the correct components will usually overcome slight neck tension variation.

 

[ofdscooby]

So I was doing some measuring the other day a spent shell is .314 OD resized is .307 and reloaded is .309 so my loaded shell is right at that .002 neck tension which seems to be optimal. But I'm trying to get this neck tension right without getting some competition bushing dies, not that I'm opposed to it im just gonna try and tinker before I spend the money. I'm also gonna take my buddies neck turner for a spin. And shave a little off then try that.

 

[MagnumManiac]

Just because your cases measure .002" smaller than bullet OD DOESN'T mean your neck tension is uniform across all cases. Differing hardness will effect the actual tension, also, not all rifles like .002", some like less and others require double that for consistency. My 300WM likes .0015" or slightly less, but this IS a neck turn chamber, even though a .002" skim gets the job done on Norma cases.
This is why bushing dies are helpful, you can purchase 2 or 3 different sized bushings and experiment up and down in tension, or you can buy several bushings, not all bullets like the same tension either.
If you try several differing tensions, you will find the appropriate tension pretty quick. I found mine with less than a dozen shots.
I like using FL style bushing dies, Forster being my favourite.

Cheers.
gun)

 

[NMwapiti]

I've been using a Wilson hand seater with my 300WSM for a while now. You can really feel the pressure required to seat the bullet. Every once in a while one of them feels a little light or heavy. I set them aside. This first picture is a group of 215 Bergers with Magpro powder. The center ring is 1 inch across. The low right shot was my fault. She groups about 1/2 MOA which I consider about as good as you should expect with a factory Savage rifle and handloads. The second picture is the exact same load, rifle, etc shot a few minutes later with my "odd" feeling seated bullets. Quite an effect.

 

[just country]

Morning try a Hornandy neck sizing die. Adjust to depth of neck. very consistant.gun)