- Location
- Jameson, SK
Full length case resizing vs neck resizing?
- Thread starter wkmiller
- Start date
Below is what I have against neck sizing and it has to do with brass quality and uniformity. The Remington case below has .003 neck thickness variation and this is "average" and some of these Remington cases have .008 or more thickness variation. And here is the problem just neck sizing these type cases, when fired the thin side of the case expands more and the case will warp and becomes banana shaped. When this case is just neck sized the case is causing misalignment with the bullet and the bore and accuracy decreases.
Below is an example of neck thickness "and body" thickness variation and having the bullet .0025 out of alignment with the bore even after neck turning. Meaning the case is out of alignment with the chamber and bore and causing accuracy problems.
When you full length resize your cases, the body of the case is not touching the chamber walls and the body of the case can not influence bullet alignment with the bore. A full length resized case is supported by the bolt face in the rear and by the bullet in the throat of the chamber. This give the case a little wiggle room and helps the bullet be self aligning with the axis of the bore.
Below a full length case when fired only has the case shoulder touching the chamber. The case body and neck have clearance with the chamber and body of the case has no "guiding" effect with the bullet and the bore. And if you go to accurateshooter.com reloading forum you will find the the vast majority of competitive shooter are full length resizing their cases.
Below the average SAAMI factory chamber has 0.00025 clearance on each side of the bullet and a match grade chamber has 0.0001 clearance on each side of the bullet. So why have a neck sized case with case thickness variations pushing your bullet off center with the axis of the bore.
Below is an example of neck thickness "and body" thickness variation and having the bullet .0025 out of alignment with the bore even after neck turning. Meaning the case is out of alignment with the chamber and bore and causing accuracy problems.
When you full length resize your cases, the body of the case is not touching the chamber walls and the body of the case can not influence bullet alignment with the bore. A full length resized case is supported by the bolt face in the rear and by the bullet in the throat of the chamber. This give the case a little wiggle room and helps the bullet be self aligning with the axis of the bore.
Below a full length case when fired only has the case shoulder touching the chamber. The case body and neck have clearance with the chamber and body of the case has no "guiding" effect with the bullet and the bore. And if you go to accurateshooter.com reloading forum you will find the the vast majority of competitive shooter are full length resizing their cases.
Below the average SAAMI factory chamber has 0.00025 clearance on each side of the bullet and a match grade chamber has 0.0001 clearance on each side of the bullet. So why have a neck sized case with case thickness variations pushing your bullet off center with the axis of the bore.
Below I have two runout gauges, a RCBS gauge and a Hornady gauge to check how straight my resized and reloaded cases are. Now think about this, the RCBS gauge below front is holding a case as if it was neck sized and the body of the case has effect on bullet alignment with the bore. The Hornady gauge in the left rear is holding a case like it was full length resized and the case body is not touching the chamber walls.
The average reloader is better off full length resizing, using good quality brass and minimum shoulder bump for his off the shelf factory rifle.
Too much of what bench rest shooters do to their brass for their custom tight chambered rifles filters down to us and is not needed in a factory rifle with our SAAMI chambers.
The average reloader is better off full length resizing, using good quality brass and minimum shoulder bump for his off the shelf factory rifle.
Too much of what bench rest shooters do to their brass for their custom tight chambered rifles filters down to us and is not needed in a factory rifle with our SAAMI chambers.
To the OP.
For bolt rifles, you can neck size only.
Dies of any make will fir your Dillon.
You can buy a neck size die, or use your FL die and set it a tenth of an inch out, so it does not size quite all the way.
If you use a neck size die, no lube is needed. If you use a back-out FL die, use some lube.
I have found that FL sized die shoots as well as neck only.
For bolt rifles, you can neck size only.
Dies of any make will fir your Dillon.
You can buy a neck size die, or use your FL die and set it a tenth of an inch out, so it does not size quite all the way.
If you use a neck size die, no lube is needed. If you use a back-out FL die, use some lube.
I have found that FL sized die shoots as well as neck only.
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
Proper sizing is far more important in the generic hunting rifle THEN a close tolerance competition rig.
The whole point of proper sizing is to control the fired case dimensions wrt to chamber. Factory chambers are all over the map, as are factory dies.. The average reloader has to understand this variation and because using the wrong combo of die vs chamber leads to BIG headaches wrt case head separation and poor accuracy.
How excited is a hunter going to get when he runs the bolt to chamber another rd and has 1/2 the case still stuck in his chamber. Conversely, how excited will a semi auto shooter be when he has an out of battery KABOOM.
We seem to keep going round in circle and the argument hasn't changed in the numerous posts you have put up all these pics and info. The right technique is whatever steps are needed to make the brass chamber properly into that firearm... no more no less.
and the proper method depends....
The OP has not answered my original questions regarding firearm and application. Without this info, there is way too much "assuming" going on.
FL can be a really bad idea.... it can be a really good idea.
Until reloaders start putting down the application, there is alot of misplaced info being repeated on and on.
For those that doubt this, just read another post here on case head separation... Guess what die he was using?
YMMV.
Jerry
RCBS FL dies . You think FL sizing caused this. Jerry , you dram to know your stuff , so why not tell us what you think is the best way to size cases for each application . Hunting , target shooting is what I'm doing . With on gun chambered in 7mm. I don't t think anybody is just plinking with the big guns and bench rest is a totally different cat.O think a lot of guys want to make accurate rnds for target shooting , at least out to 500 yards and make accurate hunting rnds. While using the same gun for both.. You said , you can't use a fork to drink soup. Can we not use a spork
- Location
- Jameson, SK
When is FL a bad idea??
I was under the impression that FL is always OK, but neck sizing is sometimes OK, or maybe even better??......
I was under the impression that FL is always OK, but neck sizing is sometimes OK, or maybe even better??......
- Location
- Jameson, SK
As in he was squishing the shoulder too much?
I'm not sure as I haven't reloaded much rifle brass other than .223 and maybe 200.308. All I know is he was resizing his .308 cases on my press using RCBS FL dies. Following the instructions that came with his dies.He had 4 or 5 case separations and quite a few pieces of brass with a barely visible ring around them. Almost halfway up the case.
- Location
- Jameson, SK
Hmmmm... I dunno.... but I'd sure like too so I can learn from it.
Following....
-J.
Following....
-J.
- Location
- Jameson, SK
When you say "a cam over" you mean maximally using the throw of the press??
If so, that doesn't quite make sense to me. Cam-over or not, what matters is how the die is set. If the die is set too tall, the cam over will do nothing. If it's set too low you'll crush the case long before the cam takes effect.
Am I crazy for thinking this?
If so, that doesn't quite make sense to me. Cam-over or not, what matters is how the die is set. If the die is set too tall, the cam over will do nothing. If it's set too low you'll crush the case long before the cam takes effect.
Am I crazy for thinking this?
The RCBS instructions say to lower the handle, screw sizer die in until it touches the shell holder. To ensure all play is removed, raise the handle slightly and screw the die in 1/8 to 1/4 turn. Return the handle to lowest position and you will feel resistance . The handle will pop as the compound linkage of the press CAMs over.
Mystic Precision
You have entered the slippery slope where "YOU" think you are the only one who knows how to reload and have crossed the line. And you also think only your comments and oppinions here have any meaning and all forum members should only follow your advice.
The OP wkmiller has made one single post here and has not come back in 35 posts and "YOU have the audacity to say only your postings matter.
When things like this happen Mystic Precision its time for you to rethink why you are in a reloading forum and think about starting your own blog or webpage.
Your reply above was arrogant, self serving and uncalled for, and thinking you are the only one in the world who knows how to reload shows your arrogance. This is a open forum and open to all, so starting your own web page where you don't have to deal with other people answering questions sounds like a good idea.
Its reloading and not rocket science and more people need to read the front part of their reloading manuals. And some people need to understand the world does not revolve around them.
You should go to the reloading forum at accurateshooter.com and say the same thing as you did above and see what reply's you get from them.
Have a nice day.
- Location
- Jameson, SK
I fail to see the arrogance or self service you speak of.
I did note a fairly firm comment made in the interest of safety, and I see no problem with that. I'd rather be warned than be blind.
Jerry helps a lot of us out on here. He does a nice job of laying out all options, and not once have I heard seen him write "you'd be better off with product X, and by the way I sell product X".
I've never seen a reaction like yours. This is weird.
-J.
I did note a fairly firm comment made in the interest of safety, and I see no problem with that. I'd rather be warned than be blind.
Jerry helps a lot of us out on here. He does a nice job of laying out all options, and not once have I heard seen him write "you'd be better off with product X, and by the way I sell product X".
I've never seen a reaction like yours. This is weird.
-J.
The problem is brass size/chamber size/headspace. The closer the fit(does not have to be perfect) the better. Choose the dies set up which accomplishes this best.
So because the shoulder on his brass is being bumped back to specs every time he FL sizes and therefore do not let the shoulder to move ahead on his fire formed cases ? So it would be better to neck size his fire formed cases and bump the shoulder when needed.
