300 win mag question

[Accuracyman]

Eric Cortina would say "Quit Neck Sizing"! Full length resize every time and move the shoulder back .002".
I agree and only full length resize.

 

[chav0_12]

With the experience I've had with 300 WM, I would only be bumping the shoulder enough to allow it to chamber. This can save your brass a little bit of life. I wouldn't fully full-length size every time. Through you should have a FL size die on hand for when you do need it. Depending on the rifle and chamber job, you could get a lot of growth in your brass and end up over working it.

 

[gohring3006]

Neck size until it gets hard to chamber then set up your FL die like Broz does in the video shared.
It could take two to three firings to get the case fully fireformed to your chamber, if you set up for .002" shoulder bump on the first firing you could be allowing your brass to stretch near the belt and you won't notice until you have a case head separation.

 

[HSmithTX]

I try to move new brass one time to fit the chamber, after that I try to minimize moving the brass as much as possible while FL sizing. Especially in the 300WM, a lot of times the brass will have a LOT of clearance on the shoulder when new. FL size without moving the shoulder, then fireform the brass, then FL every time with .0015-.002" shoulder bump for me.

Used/once fired/unknown brass I will do the exact same process as long as it chambers, if it won't chamber nicely I will size only as much as needed to get it to chamber easily and then fireform.

 

[blvette75]

I'm wondering if I should fill length size the brass for my new 300 win mag or neck size what do you guys think?

Well I used to just neck size, when I had a 300 win mag rifle with a load dialed in. But then I re-barreled that rifle to a new caliber. I found out that the reloads I just neck sized will not consistently chamber into my other rifle, (oops should have checked that prior to re-barreling, saved the barrel may switch it back some day.) From now on when I have multiple rifles of the same chamber I full size. Just my experience.

 

[Grizzly60]

There's got to be a reason the competition shooters full length size over just neck sizing.

 

[ARlife4me]

I've some of Eric's vids and am not a fan of neck sizing or turning. Doing the shoulder bump is the new wave for a reason. If shooting the once fired brass from that particular gun is already formed to your guns chamber. Full length is at your disposal, but not as necessary.

 

[VinceMule]

My loads are warm, so I have always full length sized, 180g likes to run full throttle on the pressure for best accuracy With R#22 and 215's, 3100 fps and small groups.

 

[Deputy819]

Neck size until it gets hard to chamber then set up your FL die like Broz does in the video shared.
It could take two to three firings to get the case fully fireformed to your chamber, if you set up for .002" shoulder bump on the first firing you could be allowing your brass to stretch near the belt and you won't notice until you have a case head separation.

^^^THIS^^^
The only "additional" thing I would do is to employ the use of the Larry Willis collet die when needed.

 

[Teri Anne]

There's got to be a reason the competition shooters full length size over just neck sizing.

There is, we can't afford to have a finicky cartridge slow us down or fail to feed as well as and throw us off cadence during rapid fire exercises. Moving from standing to sitting and firing off 10 well aimed shots in 70 seconds or less or in the case of standing to prone in 60 seconds or less we cannot afford any ammo issues, especially a failure to feed.

 

[FEENIX]

X2!

X3!

 

[QuietTexan]

I'm wondering if I should fill length size the brass for my new 300 win mag or neck size what do you guys think?

I'm wonder same thing... I am using peterson long brass and 1 time fired ??

There are two very distinct conversations happening in here.

1. How to resize before case stability is reached at ~ 2-4 firings
2. How to resize after case stability is reached at ~ 2-4 firings


This is the answer to 1:

Neck size only for new brass.

This is the answer to 2.

Always full length with .002 shoulder bump. Your brass will last longer and your bolt will always close even if some dirt gets in.

This is the combined answer to 1 and 2.

Usually neck size for 3 loads. Then I bump neck size with a forster die. Shoulder needs to move forward to chamber dimensions before bumping it back a 2 thousandths.

"Bump neck size" is an accurate description because the Forster bump die doesn't size the case body, but since the shoulder is moved this is still commonly NOT referred to as neck sizing. If case body sizing is needed when using a Forster bump die then a Redding bushing die or body die can be used on the body, or a standard FL die not screwed in all the way can work the body somewhat. Someone else already mentioned the Willis collet die if there is a case problem isolated to the web directly over the belt.

You'll notice for both questions there is never an answer of "set the FL die at tight as possible" because for a 300 WM there's no reason to set the shoulders back that far, all it'll do is cause you to trim a lot and most likely set you up for a case head separation.