Quick questions about new brass and neck sizing bushing selection

[Solidsnake87]

Hey guys,

Most of my equipment arrived today. I only need to get a scale, giraud trimmer, and some neck sizing bushings for my dies. I did not want to purchase the dies until I determined the measurement range I might need. I measured a fired case's outside neck diameter at .346" and an unfired cartridges's outside neck diameter at .338". Which bushings should I purchase? It would seem by reddings instructions that I should purchase a .337 bushing. Should I purchase a range of bushings? Which ones? and Why? Also, if I purchase a range of bushings, how do I know if a different bushing is needed? Redding claims the 308 Win bushing range is .335-.343"

Also, I'm trying to create a round that will take me to 1K. On advice from others, I plan on using the 175grn Matchking .308. How hard do I need to push this round to get there with accuracy? It would be nice to avoid hot loads so I can use my brass longer. I plan on using Varget powder.


Lastly, do brand new cases need to be full-length sized?

[ocabj]

http://www.redding-reloading.com/techlinepages/bushingselection.htm

[Solidsnake87]

I've read the entire entry a few times. Like I said, I would appear I would need a .337 bushing. However, I've been given the impression that I need multiple bushings. What should I get if this is so?

[rksimple]

If you plan only to use one type of brass, then just get the bushing that'll give you .002 of neck tension with the given brass. If not, get a few bushings in maybe .002 increments.

New cases should be run through an expander to knock out any dings in the necks. I normally don't fl size new brass.

For 1k and accuracy, push the 175s as fast as you can while still maintaining good accuracy. Velocity is your friend at 1k. Run some jbm numbers for an estimate on 1k velocity in your AO.

[Solidsnake87]

Run some jbm numbers for an estimate on 1k velocity in your AO.

Huh?

[rksimple]

Go here. Plug in your info. Find out what your bullet is doing at 1k given your atmospheric conditions (that makes a difference ). AO=area of operation.

[f4tweet]

Quick questions about new brass and neck sizing bushing selection

Hi, I just started reloading for .308 for my M1A. I am using some older Bonanza dies, and a friend let me use his Redding. Neither of these have bushings. Questions: Why do I need a die with bushings. What is wrong with using my standard dies? Thanks, rifle reloading noob.

[ar15barrels]

I've been given the impression that I need multiple bushings. What should I get if this is so?

0.334
0.335

[Mikeb]

I think that for a semi full length sizing and standard dies will work fine. I think the bushing dies are especially good when you are neck turning.
taks care
Mike

[f4tweet]

OK, when and why do you neck turn. I bought an RCBS Micrometer for .308. My chamber is 1.632, so I bumped the shoulder back to 1.628-1.629. For an M1A do I need to worry about bushings and neck turning? Thanks, this is the piece of the puzzle I don't understand yet.

[jandmtv]

In a semi auto, you should full length size every time. Neck turning, Bushing dies, etc... are really only beneficial to bolt guns.

[f4tweet]

Thanks, that's the piece to the puzzle I didn't know.

[Mikeb]

Yeah what Jandmtv said. If your shooting minute of moose or minute of deer or minute of "hey this is fun" you want good generic ammo in a semi. When you want to put one hole in the target (cause your cheap and want to save tape )and you are shooting a bolt gun especially something set up for single shot, you want as consistent as possible. The brass is trimmed to length, the necks are turned to consistent thickness, the flashholes are uniformed the brass is fireformed in the chamber for which it is meant and the cases are neck sized only... then you need bushings. Long range sub MOA is achieved when everything is exactly the same every shot. You get that by jumping though all the hoops.
take care
Mike

[f4tweet]

Outstanding, Thank You.

[rksimple]

Bushing dies offer the ability to size the neck of the brass only as much as it needs. You don't need to neck turn to see the advantages of this. Standard dies will squeeze the neck down overly tight just to have you drag it back through the expander. This over-working of the neck is what will cause it to split with time. A fl bushing die would be fine for a gasgun. Bump the shoulder .002-.003" and be done with it.