Case neck tension ?

Using 280 brass to make 06 cases for a rifle with headspace seems a lot of trouble considering sizing, expanding, fire-forming, and the like.
Click to expand...

I am not a fire former, I form first, then fire. Again, I adjust the die off the shell holder .014” then raise the ram. For most of that work I use a Rock Chucker, the advantage to the Rock Chucker over other presses I have? The Rock Chucker does not cam over.

Reloaders do not realize how much easier it is to size a case when the die is adjusted to reduce the cases ability to resist sizing.

“seems a lot of trouble”: The story about how these rifles got that way, for me, is worth the trip.

F. Guffey
 
What is good enough? There is a remote possibility some of this material will be read by someone that wants to know? The same possibilities exist for someone that wants to know what is possible. Then there is that someone that wants to off set the length of the chamber with the length of the case.

Then there are fire formers, they chamber a round, pull the trigger then become fire formers. It is possible to form the case first then fire.

I am the fan of setting clearance, I am the fan of cutting down on all that case travel.
 
.002 headspace clearance:

With reference to Guffey's post #56, as well as other posts advocating .002 headspace clearance, considering bolt rifles as opposed to semis, what is the purpose for setting the shoulder back for .002 clearance if not actually needed for chambering? Or is it just to ensure that proper chambering will happen every time? Is there some objection trying to maintain the same case body length as ejected after firing? While difficult to consistently achieve, depending upon the cooperation of the sizing die, I prefer the slight shoulder to shoulder resistance when closing the bolt.
 
what is the purpose for setting the shoulder back for .002 clearance if not actually needed for chambering?
Click to expand...

It is like immediate neighbor hood acceptance. It is not unlike mowing your lawn. I do not know if it is ‘the magic .002’ or the fact most are conditioned to use the term ‘bump’ and set back.

When I move the shoulder back I am forced to have case body support. Meaning when I size a case I size the case body also.

When I want to bump I use a bump press, my bump presses bump on the way up and again on the way down.
 
Guffy- I believe the .002 bump is the number most shoot for. Min clearance for no sticky bolt operation and least amount of case stretch. Makes your brass last longer. Now for a 223 that is not a big deal. Ask those that shoot 338 Lapua and such. Case life is important to those guys. Going with the .002 bump, I now have 6MMBR brass that is going on 26 times reloaded. No case seperation and no split necks.
 
Guffey,
How do you get full definition without fireforming? I'm one out here who would like a detailed description of how to form a case to full definition without fireforming.

As for the .002" clearance. What is it's purpose? I want to feel the bolt close on the round. Setting the shoulder back .002" on each loading will shorten case life. After so many firings cases need to have the shoulder set back so the bolt will close, but not every loading. How often depends on what pressure the cartridge is loaded to.
 
And feeling the bolt close on the round, slight shoulder to shoulder contact, helps to ensure that the cartridge is centered within the chamber.
 
I feel just the same with die set up, the outcome in reloading is best when there is minimum of movement in the chamber, fire forming cases , there is .001 in spring back on a fired case or the case wouldn't be ejected easily. .001 is perfect & no worries in galling the bolt lugs, I'm talking about bolt action benchrest shooting , that's my interest only.
 
Lee- Having to set shoulder back after so many loads?. I assume you neck size only?. FLS has been proven over and over to be more accurate then neck sizing/ fire forming. All most all bench shooters will use a bump die to set shoulder back .002.

Condor- feeling bolt close tighter helps center case- this is also not correct. If you have a match rifle that has been set perfect only, other wise your statement is incorrect. Enter the Savage floating bolt head.

Cw308- .001 Is a little on the tight side. If it works for you that is great, would hate to be in a match and have a sticky bolt though.

Lee- I can only speak from match shooting in so much as case stretch depending on the load. While what you say is true, most people that shoot matches are running stout to hot loads all the time. I know I do. .001 set back and a hot load will get you a sticky bolt for sure.
 
condor bravo and cw 308,
Have it right. Shoulder to shoulder contact does center the cartridge in the chamber. That's good for accuracy.
When the pressure drops the case does spring back and that aids extraction.
 
If you say so lee. Yes the case springs back, but you still will have a sticky bolt. In a match that is not good, not only time wise but will make you move your position to aid in opening bolt.now you have to reposition your body again for the next shot. Also as I said if it works for you , that's great.
 
Above post #70 noted with no hard and fast argument. Still, my ideal is to maintain, to the extent possible, the same resized body length as ejected from firing. I guess you could say this is in between sizing, but closer to neck sizing while the body retains the same length. And if slight shoulder contact can be achieved, probably better centered than if the cartridge is laying at a slight angle due to unnecessary headspace clearance.
 
Condor- yes better centering of case in a rifle that has trued. Unless your rifle is trued it is a false statement. Lee can argue that all he wants, but if you do some reading on it you will find it to not be a true statement. I only give help when I can, if you take it, that's up to you. All I do is match shooting. I do not hunt any more. I target shoot from 600 to 1400 yards now. I have tried a million things and keep what works and forget the rest. In the end, what works for you is all that matters.

PS. What you seem to be saying about your sizing is what I am talking about, FLS with a bump die. Not a neck die.

Neck dies are a waste of money, great for 4 maybe 5 loads, then you have to FLS and waste your rounds to get the fire formed again. Kinda silly. I have some from my experimenting days. I will sell them to you for real cheap if you want, they are Forester Dies.
 
Last edited:
Lee-I in no way mean to say your wrong, that is why I said if it works for you great. The idea in long range shooting is to fire,open bolt, grab case out, load new round,close bolt with out ever having to take your cheek off the stock or having to move it in any way. A sticky bolt will shoot that all to heck for sure. It will cost you accuracy and in a match, will cost you points.
 
Most of us are on the same page. I F/L size .001 head space with.001 jump, my chambering & bolt lifts are fine, if I would get hard chambering or lifts I would adjust. I don't compete only against my self, even though I love bench rest shooting & everything that goes with it. I also enjoy this forum with all your helpfull advise. Keep it going, Chris
 
Essentially all of my rifle shooting is 10 shot groups from standing off-hand, so I probably don't benefit as much from subtle nuances of loading techniques, or from a trued rifle, like would be achieved for long range shooting like 4runnerman does. Kind of got tired of bench shooting and haven't done any for about four years. Therefore I hardly ever report on accuracy loads or group sizes since comparisons with bench shooting would not be equal.
 
CB, blew out both right & left rotator cuff's. Shooting standing off hand, its hard enough combing my hair.
 
"Lee-I in no way mean to say your wrong, that is why I said if it works for you great. The idea in long range shooting is to fire,open bolt, grab case out, load new round,close bolt with out ever having to take your cheek off the stock or having to move it in any way. A sticky bolt will shoot that all to heck for sure. It will cost you accuracy and in a match, will cost you points."
__________________

No argument. You are right and it works for you. I'm mostly off the bench with long range handguns and cast bullets and low pressure loads. If I have to full length size a case to make it chamber it's an event. Mostly I size with a spacer and an expander ball that will just lets the case hold the bullet.
 
You must log in or register to reply here.
Back
Top