FL and/or Neck die

[UndFrm]

New to reloading, have been reading and watching stuff and haven't done it myself.

My question is, I have a Full Length sizing die and a seating die, do I also need a neck sizing die? This question came up while discussing the jump/jam.
Further search shows that people use the neck only sizing die to extend the brass usage. But also, there are videos from some known people who says "never neck only size, always full length".
How do I decide if I need to FL or neck only size? Try both and see which seems a better result? Or, is there a rule of hand when sizing? When saying neck sizing, I mean the one with a bushing where you can adjust the neck size.
Purpose is bench rest and I would like to adjust the jump/jam amount but I think I can do that with using just the seating die?

Thank you

 

[straightshooter1]

New to reloading, have been reading and watching stuff and haven't done it myself.

My question is, I have a Full Length sizing die and a seating die, do I also need a neck sizing die? This question came up while discussing the jump/jam.
Further search shows that people use the neck only sizing die to extend the brass usage. But also, there are videos from some known people who says "never neck only size, always full length".
How do I decide if I need to FL or neck only size? Try both and see which seems a better result? Or, is there a rule of hand when sizing? When saying neck sizing, I mean the one with a bushing where you can adjust the neck size.
Purpose is bench rest and I would like to adjust the jump/jam amount but I think I can do that with using just the seating die?

Thank you

I've been doing both for a long time as I collect my loading and shooting data. Neck sizing only works just fine, but keep in mind that it doesn't take long until those shoulders need to be bumped back. When I neck size, I always follow up with another die the bumps the shoulder back. When comparing results on target, I find no real difference in performance between the neck sized and the FL sized cases.

The main reason those who preach "never neck only size" is because there can be an issued when the shoulders are not bumped resulting in feeding problems. When you FL size properly, you'll never have that issue. Neck sizing instead of FL sizing does provide a little longer life for the cases, but that depends on how you're chamber and/or sizing die is set up. For competitive bench rest shooting, FL sizing is better to avoid chambering issues.

If you want your brass to last a long time, do the things the work hardens the brass the least . . . like, having a FL sizing die reamed where the neck is sized minimally before it's expanded to your desired neck tension. Or better yet, you can properly anneal your brass after every firing, which tends to give you good results, particularly when reloading for a factory rifle.

Best thing for you, IMHO, who is new to reloading, is to simply keep FL sizing your brass until you really understand what's going on when you fire reloaded brass.

 

[918v]

Just remember that when you FL size, don’t bump the shoulder more than .002-.004” else the cases won’t last very long.

 

[Doom]

It really depends on what you do. A lot of SRBR shooters neck size only. If you shoot very hot loads you can run into chambering issues, hard bolt closure and that will pull your rifle around more between shots. I necked sized for about ten years, 223 and 308 and went to FLS a couple of years ago and am now going back.

 

[straightshooter1]

It really depends on what you do. A lot of SRBR shooters neck size only. If you shoot very hot loads you can run into chambering issues, hard bolt closure and that will pull your rifle around more between shots. I necked sized for about ten years, 223 and 308 and went to FLS a couple of years ago and am now going back.

Hmmm??? How come you're going back?

The only advantage I can think of, in my limited experience, is one can fill the case more if that is what needed for a particular powder.

 

[DHDeal]

A serious benchrest shooter typically will have custom sizing dies. Harrell's is a good example of a company that will make them and Forester makes a 3 die set. These dies typically will be called something like shoulder bump neck die. Harrell's will want 3 cases to measure and the last time I bought from them only did this with a limited number of cartridges.

There is never a reason to not experiment and try stuff. Worst thing you will do is waste money but you will gain personal knowledge for that possible wasted money. I have spent more money on sizing dies than on seating dies by a large margin. Many of those sizing dies will never see the light of day again and my son will just shake his head and ask the air what the hell was he doing with these dies after I'm gone. He already knows I can get off the chain so shouldn't be too surprised.

I will use FL dies 95% of the time with a few exceptions. Those exceptions are dies for my BPCR's and a couple benchrest rifles. The BPCR's (black powder cartridge rifles) are neck only as the cases never need to be FL sized and the benchrest rifles use Harrell's sizers. Everything else gets FL sized (many safes full of rifles) and they all shoot great.

You do you and try what you want. As you mentioned, you are just starting and need to learn that a lot of what you read is not necessarily going to make a difference for you. I would say to you to buy very good measuring tools and use them. I will use a good set of calipers and different micrometers almost daily and I hate money.....

 

[Doom]

Hmmm??? How come you're going back?

The only advantage I can think of, in my limited experience, is one can fill the case more if that is what needed for a particular powder.

I'm shooting factory rem 700's and in both 223 and 308 I get about 0.005" growth in overall length in each resizing with about 0.001" setback on the shoulder. I know in the 308 the most growth on firing is mid case. Don't remember the amount but it's enough to cause the growth on resizing.

Since my loads are below max I don't have an issue with hard bolt closure when neck sizing so I guess you can say I'm lazy. I'm not shooting competitively and most of the time only at 300yds so I honestly can't say accuracy is an issue. I'll probably keep another set of cases for the 308 to load for longer ranges and will FLS those.

 

[Maurygold]

Lots of long winded and only partially correct answers. USE A FL DIE ONLY.

You aren’t shooting benchrest and using a FL die doesn’t overwork brass so that’s all you need.

 

[DHDeal]

Lots of long winded and only partially correct answers. USE A FL DIE ONLY.

You aren’t shooting benchrest and using a FL die doesn’t overwork brass so that’s all you need.

Ha! I'm guilty of being long winded. I wish I had the Morgan Freeman meme where he points up and says "he's not wrong" for your post.

 

[ECK]

Seems like over time there have been different trends among different reloading crowds. In the last decade a lot of PRS guys were advocating neck-sizing or bump-sizing and not FL sizing. Fast to the 2020’s and the trend shifted back to FL sizing. I’m sure there are still some dedicated disciplines where neck or bump sizing is the preferred method….

For me, I went back to FL sizing with a neck bushing. But I also include a decap die and mandrel die into my brass-prep process and have the expander ball and decap pin removed from the sizing die.

Based on my testing, it sure seems like using the mandrel die to set neck tension was the one thing that really improved my precision and SD numbers. Somebody else can probably explain it better than me, but relying only on a bushing to set neck tension is dependent on all the brass having uniform neck wall thickness. So the neck bushing in the sizing die is just there to squeeze the neck dia down a little after firing, but the actual neck tension is set with the mandrel. The expander ball in the sizing die kind of does the same thing but it seems like the mandrel die does a better job (albeit an extra step) and you can change out the dia of the mandrel insert to have more control over how much (or little) neck tension you want.

 

[straightshooter1]

I'm shooting factory rem 700's and in both 223 and 308 I get about 0.005" growth in overall length in each resizing with about 0.001" setback on the shoulder. I know in the 308 the most growth on firing is mid case. Don't remember the amount but it's enough to cause the growth on resizing.

Since my loads are below max I don't have an issue with hard bolt closure when neck sizing so I guess you can say I'm lazy. I'm not shooting competitively and most of the time only at 300yds so I honestly can't say accuracy is an issue. I'll probably keep another set of cases for the 308 to load for longer ranges and will FLS those.

Yeah, with factory barrels producing a lot of movement of the brass, neck sizing does make for longer lasting cases. . . especially if one is using softer brass like Federal's.

 

[DHDeal]

Seems like over time there have been different trends among different reloading crowds. In the last decade a lot of PRS guys were advocating neck-sizing or bump-sizing and not FL sizing. Fast to the 2020’s and the trend shifted back to FL sizing. I’m sure there are still some dedicated disciplines where neck or bump sizing is the preferred method….

For me, I went back to FL sizing with a neck bushing. But I also include a decap die and mandrel die into my brass-prep process and have the expander ball and decap pin removed from the sizing die.

Based on my testing, it sure seems like using the mandrel die to set neck tension was the one thing that really improved my precision and SD numbers. Somebody else can probably explain it better than me, but relying only on a bushing to set neck tension is dependent on all the brass having uniform neck wall thickness. So the neck bushing in the sizing die is just there to squeeze the neck dia down a little after firing, but the actual neck tension is set with the mandrel. The expander ball in the sizing die kind of does the same thing but it seems like the mandrel die does a better job (albeit an extra step) and you can change out the dia of the mandrel insert to have more control over how much (or little) neck tension you want.

I would say that about covers it. Mandrels are another step that I am willing to take. 21st Century has taken my money often. I think I said earlier that I hate money.