reaming vs. neck turning vs. annealing

[atlatl]

I have reloaded and cast bullets for 20+ years and have never needed to do any of the above procedures. I now have some 300 WSM Norma brass that has been loaded a dozen times and find that the bullet does not freely drop into a fired case, but drags just slightly thru the neck. Have the numerous firings a resizings caused the brass in the neck to flow forward and thicken? How do I determine this and is the solution inside neck reaming or outside neck turning? I realize that this question relates more to jacketed bullet reloading due to the higher pressures, but the members here seem to have better answers than obtained elsewhere. Thank you for reading this rather long post.

[scb]

My take. First I'd cast the chamber. If you neck diameter of your loaded round is a few thousands of an inch smaller than the neck of the chamber cast I wouldn't worry about turning or reaming. Unless you think doing so might enhance accuracy. My guess is that annealing may well be required. Your brass may be getting hard enough that it is actually springing back when fired. Just my $.02.

[gnoahhh]

I like scb's thoughts. First thing to check. If your brass is flowing a bit then maybe it is time to consider turning or reaming. I prefer turning myself, but others prefer reaming. Take your pick. Also, if your brass is flowing then I would consider where it's flowing from, ie: is the brass getting thinner toward the base and tempting a case head separation? If those conditions are occurring it may indeed behoove you to reconsider the loads you're shooting, IMO.

[Echo]

From what I read, neck turning is preferred over reaming. Provides a more uniform neck thickness.
Otherwise, I have to agree with scb - annealing will probably solve the problem. How many cases are we talking about?

[scb]

How do I determine this and is the solution inside neck reaming or outside neck turning?

I only neck ream when making wildcat brass and may have to remove the "donut" in the neck. Turning, to my way of thinking, gives you a far more consistent and truer neck wall thickness.

[onesonek]

I only neck ream when making wildcat brass and may have to remove the "donut" in the neck. Turning, to my way of thinking, gives you a far more consistent and truer neck wall thickness.

Just to expand on that a bit,,,,,,
Turning trues the necks as stated, which is sometimes for close tolerence chamber fits, otherwise it also aids in more even release, for optimizing accuracy. Reaming as mentioned, is to remove the donut as mention, for the most part.
Just wanted to add, the sharper the shoulder, the more this occurs. A 30^ shoulder will eventually form more of donut than say a 25^, and a 40 ^ will be more. You don't see it or feel it as much on the shallower shoulders, as the brass continues to flow forward increasing the case lentgth. This is why on say like the 30-06, one needs to trim length more, and on the AI's less, but on the AI's reaming is needed where not so on the 06.

I don't have any experience with the .300WSM, but suspect it with a 35^ shoulder, would develope a donut to a point. Generally you can feel this when sizing the case as added resistance once the expander button is nearing or at the bottom of the neck on the down stroke. If not reamed, the donut just get swaged back into the case, leaving a lip at the shoulder neck juncture,,,which isn't the ideal situation. It creates turbulence and gas flow restriction, which results in pressure fluctuations. You can see this on a chronograph, when comparing new brass loads, to say the same load from same brass lot loaded multiple times, but not reamed.

On my target/long range brass, I turn the necks true when new. And with the AI's I ream every second loading, sometime every loading, depending on the load and pressure. I can't say the second is always necessary, I just always have to be sure, and it seems I always am removing some amount of brass when doing so, even if not very much.

[Bass Ackward]

I like turning for jacketed for uniformity of neck tension. With jacketed, it's all about the case. Turning here is clearly superior. But a jacketed bullet can guide itself in.

It's just the opposite for cast that is frail and dainty. I want that cast slug controlled in line with the bore. And that die grabs that case and forces it into alignment during the cut. For cast, it's all about alignment and reaming provides superior performance for me.

[felix]

There would be no measurable difference by cutting the neck either way AFTER the case is shot. Cut just enough, several times if need be, once after each shot, to eventually being only barely hearing a scrape when inserting a boolit into a fired case. You want the cases to be CONSISTENT in boolit feel/sound, and it should be something on the order of a click in sound. ... felix

[Tatume]

Atlatl,

If a bullet enters the neck of a fired case, the neck is not too thick. It is okay if it drags a bit. It is only when the neck is so thick that a bullet cannot be forced in that the neck is getting thick enough for concern. In your case, don't bother to ream or outside turn.

However, if you're worried about it, use a neck reamer on the fired, unsized cases. It can't hurt anything. I like the Forster Original for both neck turning and neck reaming. On a sporting rifle there is no accuracy advantage to outside neck turning, and reaming is significantly easier.

On my bench rest guns, outside neck turning is necessary because of the fitted necks, and I hasten to point out that a bullet cannot be pushed into the fired cases either. They are that tight. These cases are carefully controlled for thickness.

The bullet in the fired case test is a go/no go test for sporting rifles, and is designed to keep people out of trouble. A case can get so thick that chambering the cartridge "crimps" the case neck into the bullet and increases bullet pull so much that pressures increase 20,000 psi or more. This condition is to be avoided, and the bullet test is sufficient to do so.

The over-long condition causes exactly the same problem. Always check cases for length after sizing, as it is much more common for dangerous lengths to occur than dangerous thickness. If cases grow to the length specified in your reloading manuals, trim 0.015" from them. Again, I like the Forster Original for this operation.

Take care, Tom

[felix]

Tom, zero clearance is desired only when the projectile is shot with current load for the best accuracy. Any tighter due to projectile expansion while in the case plays hell with groups. Don't ask me how I know. ... felix

[Tatume]

Hi Felix,

I'm sure you know this, but maybe others don't; the outside neck diameter of a loaded cartridge is specified on the barrel of a good bench rest gun. The neck of the (usually Lapua) case is cut to provide exactly this diameter. The ammunition is a near perfect fit in the chamber, and there is no danger of high pressure caused by a jammed bullet. Also, barrels are typically cleaned after every 20 rounds fired, so there is no fouling built up to cause problems. The equipment and techniques are different from sporting rifles.

Take care, Tom

[felix]

Very true, Tom. Perhaps you can obtain our past threads about making the standard military Swede shoot boolits. These guns have wide and long throats, i.e., freebore plus leade. Bob, 45-2.1, solved the problem by following the above mentioned BR techniques. The ultimate problem was getting cases having necks thick enough to play fair. Only certain military 30-06s brands would work after being cut down for the Swede cartridge. Metal characteristics plus case capacity were used to make a slow powder work for those heavy boolits in that wild stock twist. Check it out; some interesting gyrations with plenty of reading fun. When it is all said and done, a gun is a gun and they all require attention in common. ... felix

[303Guy]

... the bullet does not freely drop into a fired case, but drags just slightly thru the neck.Why would this be a concern? Does it not mean that the brass is now hard enough to spring back to almost grip the boolit without sizing. Is there clearance after a boolit has been seated?

My paper patched pig gun likes this scenario and is quite accurate with a tight fitting neck and boolit. In fact, a loaded cartridge is actually tight to chamber. But that's paper patched - not the same as plain cast or j-words and the load is not max.

What kind of pressures would cause brass flow into the neck region with cast boolits? I've had 'dough-nuts' forming but have ignored them as I don't seat that deep.

[felix]

Generally speaking, knock off the load a little when the donut forms, or shave off the donut. I prefer the latter, keeping the cases as consistent as possible for the same loading. Sooner or later the donut will not form again, depending on the brass flow which depends on the hardness of the brass. If using the former method, powder speed might have to be slightly faster for the same accuracy because the case shape was opened up slightly at the most constrictive point. Of course, you can harden up the boolit to eliminate some of its expansion. All of these operations can be seen to effect accuracy the good way or the reverse using a gun that can see the changes. ... felix

[MtGun44]

"Your brass may be getting hard enough that it is actually springing back when fired. "

ALL brass cases, ALWAYS spring back when fired. Just in slightly varying amounts, based
on the hardness of the brass, which slightly increases every cycle as the case is expanded and
resized. Once the neck brass is too hard, it will crack when fired. Other cases in the same lot
that have been cycled the same number of times need to be annealed in the neck to take
out the excessive work hardening and extend the life of the case in the neck area. If
the failures are in the case base area, nothing can be safely done by heating because the
brass in that part of the case MUST be hardened by work hardening to survive normal
firing pressures (for rifles).

Annealing has essentially nothing to do with neck reaming or outside turning, other than
it is a specialized treatment for a case neck under certain conditions.

Bill

[atlatl]

as expected reasonable answers based on experience. thanks, btw I trim to length regularly and as stated above the sharp shoulder 300wsm requires this far less often than an '06 (the only advantage of the wsm in my opinion) but I have never noticed a donut forming at the neck shoulder and I regularly examine the case interior with a fiber optic light - one case head separation lead to a fair bit of paranoia.

[XWrench3]

well, the only one of the above i have tried is annealing. and without an accurate way to measure the heat, all i did was ruin a batch of brass. i over annealed them, meaning there is very little neck tension on them. i did save some of them, to use as tools, or modify in some way or another. i just never know what my strange little brain may think of next. i am going to buy a hornady annealing kit and try doing it that way, but it will not be a full lot of brass. just half a dozen or so, until i know what i am going to end up with. as for the other items, they are supposed to help with accuracy. but in most of my guns (all hunting guns by the way) i can get moa or better. so, is it something we need, or something we THINK we need? i can not answer that, without trying them.

[Doc Highwall]

XWrench3, next time you go to the range keep an eye out for brass that you reload for to practice on.

[MtGun44]

Xwrench3,

If you want to recover that brass - esp if it is bottleneck rifle brass, expand it and then
resize it (only the neck will resize) and expand it and resize it a few more times. This will
bring the brass back to normal hardness in 2-3 cycles usually, maybe a few more if your
expander is not changing the size much.

Bill

[nanuk]

well, the only one of the above i have tried is annealing. and without an accurate way to measure the heat, all i did was ruin a batch of brass. i over annealed them, meaning there is very little neck tension on them. i did save some of them, to use as tools, or modify in some way or another.

if annealing softens, working hardens and over annealing ruins brass, then why can't you take and resize those ruined cases a few times to see how many are required to bring them back to a hardness that is usable?

it would only require you putting them in the neck size die, and cycle them a few times with the press.

Also, could you not save them and use them as Single Shot loads? could be handy to have a few in the truck for when you need to dispatch animals when you are too close for a full power load. I'm thinking here about a light pistol powder load with a heavy boolit.

Could work great for "JackLighting" also.

[Von Gruff]

I will ream, turn and anneal as the situation and brass demands. They each have a different and specific use and purpose and without understanding the needs, more harm can be done than good. Reaming is for donuts. Turning is for neckwall thickness and annealing is to controll brass hardness. To use one method when another is required can cause more problems than it is supposed to cure. They are all usefull tools to have in our search for accuracy ( or to make less available brass) with safe fitted brass that has a long usefull safe working life.

Von Gruff.