Neck size or FL size 6br?

[Flouncer]

Not to be obtuse but I thought that was the point of neck sizing. The fired brass conforms to the chamber and then you just size the neck down to hold the bullet.

What he said. My understanding was the original case blew out and expanded to fit the chamber. Then it springs back to some degree, but it is fireform fit. It seems to me counter intuitive that it would be an ever changing dimension. Maybe one can analyze this further for us. Thanks.

Obviously there is some flaw nor misunderstanding in my logic, as the winning shooters all "FL" size and shoulder bump. Does it have to do with the fact that comp shooters run way higher pressures in their custom actions ??

 

[BoydAllen]

Fellers.....this gets into the area of testing rather than just visualizing. In my experience, the best competition shooters try different things and stick with what works. It is a very straightforward process. If you can neck size and never have a bolt get tight, you are shooting light loads, which is fine, as long as the results are what you are looking for. In short range benchrest, hot loads are common, and the need to be able to shoot fast is very real. If you are not in that sport, your reality may be significantly different. Also, in order to understand the FL every time crowd, you need to have used a FL die that is a close fit to your chamber. My 6PPC die sizes the back of the case less than .001 and less at the shoulder. Compare your fired and sized cases. Is the difference that small? Bottom line...do what works best for you.

 

[mattri]

So if fired cases have a bigger variation than that is it because the individul cases stretch or spring back to different degrees and then with your FL dies your "ironing out" that small variation? I hope that's it because that makes sense.

 

[BoydAllen]

If I shoot neck sized cases, they may not all chamber the same, and if they don't, groups will suffer. It is really that simple. What sort of rifle are you talking about, and what dies?

 

[mattri]

I don't have a 6br, I'm just trying to piece some information together. Thanks again for all the great replies, Matt.

 

[superlight93]

If by factory neck die you mean the old style one piece variety.....wash your mouth out ;-) They are the worst possible. If you are talking about bushing neck die, it depends. As far as getting a Harrell die goes, what you describe will work. Just remember to make the load a hot but safe one. I prefer more than one neck sized firing, to make sure that the case is as close a match to the chamber as possible. Once you get your bushing size down, in steel, buy one in carbide.

Wash your mouth out! Boyd you are one funny guy! I got a good chuckle
BTW I agree with you 100%

 

[SS427]

Does anyone have any test targets to show the advantage of one over the other? Surely someone has shot 5 groups with neck sized brass and compared it to 5 groups shot with FL sized brass. I would do it, but I don't have any quality neck dies and quality FL dies in one caliber.

 

[BoydAllen]

Otter,
I think that you miss my point....perhaps. The best short range benchrest shooters in the world FL size. (with dies that are a very close fit to their chambers, paying close attention to shoulder bump) Worry about something else. If your loads are low enough in pressure that you can get away with neck sizing, fine. If you have a harder bolt close during a group, I suggest that you skip that round, and try another.

 

[Frankr]

I have neck sized only since i had my first 6BR some 12 years ago and have never had a problem with just neck sized cases..as a mater of fact if you look at the post"how accurate should my 6BR be" all the targets i posted is on neck sized cases only..i found they do go through a spell of some tight and some not then they all get to a point of a slight crush when i close the bolt and i have had one set of twenty cases i shot for six years..i only used them for a match or to punch little holes..and none of my varmint cases have ever been FL sized.and never will.
But where i have ran into problems is at a match where conditions made me go up on the powder to the place where the cases went in very very tight and came out with the click.. so i have got a harrels FL die and i have been working with it but still at this time i have never got my 6BR to shoot as well on FL sized cases as i have on neck sized only cases..i use a redding comp bushing die(i must have a good one).. and i run my 6BR(14 twist) with 65-68 gr bullets at @ 3,500FPS on neck sized only cases..But im going to trying to get this FL sizeing down..but at this time both of mine shoot better on neck sized only cases...But thats the way stuff works for me,,everyone even close shooting friends say FL , but does not work for me...some say if you seat the bullet below where the neck is sized it wont shoot..i neck half the neck, seat a 66gr fowler in 7/8 of the neck ..and they just shoot..everythink everyone says does not work for me..Hey i just go with what shoots..But i dont like to get stickey cases that are hard to get in or out,so i will keep working on this FL set up.

 

[BoydAllen]

FJIM,
I am a firm believer in, "If it works for you that is all that is needed." About your FL die, about .3 up from the head, and at the shoulder, how much does you die reduce the diameter of the case? Also, How much are yo bumping shoulders when you FL size. It the past, there were more shooters that shot lower pressures with the PPC. If your BR aggs. well at lower pressures, and because of its slightly larger capacity, can produce higher velocities (in line with what a PPC needs higher pressures to achieve) at those pressures, you may be having your cake and eating it too. One thing that I have verified, a tuner allows one to move the node without changing the load, it also broadens the sweet spot. How long is your barrel, and what does your rifle weigh?
Boyd

 

[Frankr]

boyd two rifles. one weighs 11.5lbs and one weighs 10.0 lbs.. the harrells die is bumping the shoulder about .001
but i have ran into some problems,, i did as TB said in his book.. i took three cases that were fired 4 times and only neck sized. set up the die so the bolt fell 3/4 way down, check at .001 bump..then started sizeing a few cases and it some were right on, some bumped .002 ect.. so im thinking just like with the neck sizeing maybe i need to run a shoot and size cycle on all of them to get them all consistant. then may need to retune the load for them cases..one barrel is 21.5" and one barrel is 24"..

I did check the base with a caliper but cant remember the reading but were good.
i did the slide the caliper down the case thing and it was right on , top of shoulder and then sized was about a 1/4" down so the die seems good..I also glued the action in, i wasent happy with the vibration i felt in the stock.havent been able to shoot, its like 15DEG F out,.right now.

 

[SS427]

Hey Boyd, yea, I get it. I was hoping someone could post groups shot with FL sizing and neck sizing and show conclusive proof one is better than the other. Sure would go a long ways toward resolving this discussion.

 

[BoydAllen]

Given that most if not all short range Benchrest matches are won using FL sized cases, and that these are the most accurate rifles in the world at those ranges. I think that it has been resolved. IMO the common problems with FL sizing are due to the poor match of dies and chambers, and in those cases reality may be significantly different. If I was trying to make straight ammo for a big factory chamber, I would probably prep the brass and run it through a Lee collet die and then someone's body die, paying close attention to shoulder bump, gauging every case and readjusting and re-bumping those that needed the die set lower to get there. Then, I would probably seat with a Forster micrometer seater. checking for consistency of seating depth as I went. Then I would sort with a concentricity gauge, foul the barrel with the crooked ones, and get serious with the straighter ones.

 

[SS427]

That's good informatin Boyd. I may have to get a Harrels die for my 6mmBR and run a test for myself. I'm curious to see what the actualy difference on paper would look like. I would keep pestering you, but Tony Boyer wrote in his book you need to FL size the 6PPC, and Lester Bruno told me the same thing over the phone. So I am sold on the idea, at least with the 6PPC and hot loads.

I'm not sure if I run a hot load in my 6BR or not. I was running 30 grains of N133 and never had any problems just neck sizing. I'm now running 31 grains and they do seem to come out a little tighter. I also tried what I consider a pretty not load of H4895 and they certainly seemed to come out tighter. I could be at the point where I need to FL size them.

 

[BoydAllen]

Some time ago, a friend and I shot side by side at a local range,with good conditions. I shot my PPC and he, a well done slow twist Br. His accuracy was at a level that would have been competitive at any match. He was shooting custom 67gr. bullet and a relatively slow 30.5 grains of 133. Just because one caliber likes something does not mean that another that is close, but not the same will like the same things. Some of the best shooting that I have seen was with relatively mild loads. I think that it all comes down to listening to your rifle, and giving it what it asks for.

 

[Flouncer]

Given that most if not all short range Benchrest matches are won using FL sized cases, and that these are the most accurate rifles in the world at those ranges. I think that it has been resolved. IMO the common problems with FL sizing are due to the poor match of dies and chambers, and in those cases reality may be significantly different. If I was trying to make straight ammo for a big factory chamber, I would probably prep the brass and run it through a Lee collet die and then someone's body die, paying close attention to shoulder bump, gauging every case and readjusting and re-bumping those that needed the die set lower to get there. Then, I would probably seat with a Forster micrometer seater. checking for consistency of seating depth as I went. Then I would sort with a concentricity gauge, foul the barrel with the crooked ones, and get serious with the straighter ones.

Thanks for taking the effort to type this out. I agree with you when you said it's decided because the BR crowd that wins uses very specialized FL dies. If it's all right, can we expand on your post regarding the micrometer seater and the Lee Collet dies ?

 

[Steve Blair]

Given that most if not all short range Benchrest matches are won using FL sized cases, and that these are the most accurate rifles in the world at those ranges. I think that it has been resolved. IMO the common problems with FL sizing are due to the poor match of dies and chambers, and in those cases reality may be significantly different.

[br]
Boyd is exactly right on matching the die to the chamber. My .284 Shehane uses a Warner Tool sizing die and a Wilson seating die reamed with the chamber reamer. The ammunition produced is straight, chambers easily, is not overworked and provides fine accuracy. If the results really matter, I highly recommend the Warner die.

 

[BoydAllen]

Flouncer,
Expand away.

 

[bozo699]

Boyd,
I think he wants you to expand on it!
Wayne.

 

[Flouncer]

It's slightly off topic, or "drift". The micrometer seating dies. I don't understand. If I sort bullets or hypothetically they are identical, and I load them with a non-micrometer. But I measure very carefully with any of several methods. Carefully. Repeatably. I shoot and carefully analyze, and find the best length. I don't change the die setting. Other than getting another arbitrary reading off the micrometer, where is the benefit ?

Does anyone else make a collet die ?

With the Lee die, can't neck tension accurately and repeatably be controlled by minute reductions in the mandrel ? Couldn't the same care that bushings-type resizing be applied to a collet and mandrel with benefit ??

Again, Merci beaucoup