Neck Turning vs Neck Reaming
- Thread starter Reed
- Start date
Many years ago, like 30 or more I played around a bunch with inside neck reaming with the Forster. Even had them custom grind some reamers for me. Not in a single test did inside neck reamed brass group as well as outside turned or left as is. Haven't even considered it since then.
Ian
Notorious member
Outside turning a resized case which has a thickness variation in the neck area will result in a neck with uniform thickness but is off-center in relation to the shoulder and body of the case. This is a real problem when running loaded neck clearances below .002".
I've wasted a good bit of money on Forster inside reamers and even purchased the less expensive chucking reamers in half-thousandth increments to get what I needed, in fact they will only work when using an outside supporting bushing of an exact size, and STILL won't make the neck thickness uniform. As Rick said, don't waste your time. The solution is to outside-turn the necks with a very snug, lubricated mandrel inside the neck, and fire-form the brass with a nearly full-power load before proceeding to use if for business loads.
I've wasted a good bit of money on Forster inside reamers and even purchased the less expensive chucking reamers in half-thousandth increments to get what I needed, in fact they will only work when using an outside supporting bushing of an exact size, and STILL won't make the neck thickness uniform. As Rick said, don't waste your time. The solution is to outside-turn the necks with a very snug, lubricated mandrel inside the neck, and fire-form the brass with a nearly full-power load before proceeding to use if for business loads.
Reed
Active Member
I've been reading a few threads in other forums about this. There are some guys who say that you won't see a difference in your groups, turned vs unturned. One theory was that the case has expanded away from the bullet long before the bullet had any significant movement, and compared to the thousands of psi the bullet and case were already under, any influence caused by differences in case neck tension among rounds would be insignificant. Interested in your opinions. Assuming I don't have a clearance issue I'm trying to correct, would I be wasting my time and money buying and using an outside neck turner?
Depends?
If you have thick necks it might help some. Where it really can help is in tight necked guns that require turning to allow the loaded round to chamber. Those guns also tend to be made on precision actions with barrels and chambers very much centered. Think BR guns.
Our standard rifles have less well centered barrels and chambers. Our actions have some slop too. The benefits of a turned neck are often lost in a sea of imprecision.
Give it a go. I did long ago in a 22-250. I got a few blisters, learned a few things, and got no better accuracy.
If you have thick necks it might help some. Where it really can help is in tight necked guns that require turning to allow the loaded round to chamber. Those guns also tend to be made on precision actions with barrels and chambers very much centered. Think BR guns.
Our standard rifles have less well centered barrels and chambers. Our actions have some slop too. The benefits of a turned neck are often lost in a sea of imprecision.
Give it a go. I did long ago in a 22-250. I got a few blisters, learned a few things, and got no better accuracy.
Brad is right, if your using an off the shelf rifle the odds are great that you will see no difference with turned necks and not turned. It certainly can be an accuracy benefit but at best it's a small benefit. First thing ya need is a rifle capable of seeing the difference and most can't.
Ian
Notorious member
I'm going to disagree with both Brad and Rick about non-precision rifles benefiting from a neck turn. There IS a lot of "depends" regarding the whole subject, but most decent factory and military rifles can and will outperform most people's wildest expectations for both velocity and accuracy using cast bullets if the ammunition is crafted to each rifle's specific needs. Without getting into the deep esoterics of all that but to speak generally, UNIFORM neck thickness and uniform bullet pull become important (a limiting factor if not addressed) to the pursuit. Most people will not agree with this because they simply have not dug that deep into cast bullet performance with their rifles and therefore haven't witnessed much improvement from neck-turning their brass. As a side note, when I turn brass for standard chambers, all I'm doing is removing material from the thick side, attempting to get uniformity of thickness all the way around to under half a thousandth variance. Often, this only involves the cutter touching 50% of the circumference of the brass. I want to remove as little material as possible to achieve concentricity and uniform, straight bullet release, because most of the time the less neck/chamber clearance, the better for cast bullets.
F
freebullet
Guest
Ive never bothered.
The consensus seemed to be if the neck has a thick spot so does probably the rest of the case. Only so much fixing can be done before you just need to get better more consistent brass.
The consensus seemed to be if the neck has a thick spot so does probably the rest of the case. Only so much fixing can be done before you just need to get better more consistent brass.
The following is based primarily on my experience with jacketed bullets. Let's say you have a "perfect" rifle. Everything is absolutely concentric about the centerline of the bore axis. If your loaded ammo has a neck diameter of say .338" and your chamber neck is .350" you have a lot of slop. Decreasing case neck diameter will only increase that amount of slop. You can overcome this to some extent by neck or partial case sizing. In a loose chamber the round will lie on the bottom of the chamber and everything is off a bit. If your chamber neck is .340" and your ammo is .338" you are at BR standards, at least with respect to neck dimensions.
USSR
Finger Lakes Region of NY
Unless you have a tight-necked chamber that requires you to neck-turn your brass, it is a total waste of time. I shot in 1,000 yard F Class competition for many years and experimented with this a bit, and found that Lapua brass outshot any neck-turned brass that I could create. Buy quality brass and cry once.
Don
Don
Not a BR shooter nor do I buy Lapua brass. I turn converted cases for 300BO as my chamber is tight for cast. Found some once fired supposedly 'good' 300BO brass and surprise! Big variance in neck thickness! So now I use the RCBS tool for all cases. The McGowan AR 1:10 barrel loves the hornady 150 SPP. My problem with cast is getting the PB flat enough for sub MOA @ 100. Never turned any 308 MG LC brass, I'm not that good. I agree with Ian, try and see. Reaming removes the donut at the shoulder.
Ian
Notorious member
That's the main reason the reamers exist, and they do a pretty decent job of it.
I've turned a heap of 7.62x51mm machine gun brass, the thickness variation is usually on the order of 1.5 to 2 thousandths, but it's pretty good brass if you spend the time to fix the primer pockets, length trim, neck turn, sort by internal volume, and draw the necks to a uniform, partial anneal.
I tend to agree.
I used Win 223 brass when I shot highpower. I always used a tubing mic and sorted brass by neck wall variation. Under .001 variation was 600 yard brass, 1-1.5 thou was 2-300 brass. Over 2 was practice or trash. I never had an issue getting 200 plus cases for 600 from a bag of 1000.
Sorting by neck variation means you also sorted by case wall variation. His helps eliminate any tendency for the case to become banana shaped over time.
Reed
Active Member
I have one of the old Lee Target Model Loaders for 30-06. For neck reaming, it uses a neck sizing die and a hand-crank reamer. The case stays in the die while being reamed. I've read that since the neck is constrained by the die, it will keep the thickness of the neck uniform and concentric. Seems reasonable ..... I haven't used it enough to decide if the results on the target make it worthwhile. There's a good reason for that. It's a pretty good workout processing more than a few rounds, which is why I was thinking about an alternative if I'm going to continue experimenting with neck uniformity. I was looking at the RCBS tool that uses a pilot that reams the inside (doughnut only???) while the outside cutter turns the neck, and was hoping that someone would have some specific experience with that tool. Anyone?
I'm always impressed by the helpfulness of the posts in this forum. It's good to get both sides of the issue, and Ian's posts are pretty compelling for taking the extra steps. I have an abundance of military brass that might benefit from a bit of turning (and trimming, and annealing, and primer pocket cleanup). On the other hand, there are an abundance of folks who have observed that for them, it's not worth the effort. Tony's thought about possibly ending up with a sloppy fit in a large chamber seems convincing. Being retired, my reloading budget is necessarily modest. When I was working, I'd already have bought one to experiment with and would have thought nothing about spending the money. So, I'm still undecided, but I now have a better perspective of the issue thanks to you guys!
I'm always impressed by the helpfulness of the posts in this forum. It's good to get both sides of the issue, and Ian's posts are pretty compelling for taking the extra steps. I have an abundance of military brass that might benefit from a bit of turning (and trimming, and annealing, and primer pocket cleanup). On the other hand, there are an abundance of folks who have observed that for them, it's not worth the effort. Tony's thought about possibly ending up with a sloppy fit in a large chamber seems convincing. Being retired, my reloading budget is necessarily modest. When I was working, I'd already have bought one to experiment with and would have thought nothing about spending the money. So, I'm still undecided, but I now have a better perspective of the issue thanks to you guys!
I look at the neck as a bushing for a shaft. Make the bushing thinner and we have more slop on the outside. As mentioned, partial neck sizing can be of some help, but then we hav bullet pull issues.
I made a bunch of 6.5x55 brass from some heavy milsurp brass. I was told it was a lesson in frustration by some. The necks got heavy enough I turned them just enough to clean up. I made like 20-25 then of coarse some factory virgin fell into my lap.
The turned brass shot exceptionally well. A time consuming job.
The factory brass initially was crap. Me being me I wanted to know why. It was neck wall thickness.
The old swedes were known to have generous neck chambers. This one was no exception.
I use M dies quite a bit. I did on this one as well. I have Loverin and bore riding designs for the 6.5. On this swede I got the M die set up so they would still chamber without removing the bell. The brass self centers for the most part. Bullets were seated out to engrave upon closing the bolt.
This rifle went from a turd to down right scary with the right guy on the trigger.
A fairly large bunch of folks go to a no turn spec Lapua reamer any more. The time and effort put into to turning has to be for love and nothing else.
I forget what wildcat I was working with years back. Almost had to ream first, and it still left enough meat to taylor to the chamber by turning. That was not an act of love, more stupidness than anything.
One of you gents will have to explain how reaming just moves the center line. And can still have an off centered neck. Ends up like not having your 4 jaw chuck dialed in right. You can still drill a round hole, just not dead center. If you want to pull hair out, expand your vocabulary and be prone to drinking heavily, get a cosintrisity set up.
To me bottom line is, the gun and everything that has to do with it, ALL of it has to have a great deal of promise to begin with. If it won't shoot 1" @100, neck turning ain't gonna help. Other things need to be tried, things need to be measured. However, Once everything has come together and it shoots bug holes, you can't wipe the grin off, nor can you buy that much satisfaction.
I have pounded tons of sand in rat holes over the years. Just as anything, "you don't end up with anything better than what you start with".
Jeff
I made a bunch of 6.5x55 brass from some heavy milsurp brass. I was told it was a lesson in frustration by some. The necks got heavy enough I turned them just enough to clean up. I made like 20-25 then of coarse some factory virgin fell into my lap.
The turned brass shot exceptionally well. A time consuming job.
The factory brass initially was crap. Me being me I wanted to know why. It was neck wall thickness.
The old swedes were known to have generous neck chambers. This one was no exception.
I use M dies quite a bit. I did on this one as well. I have Loverin and bore riding designs for the 6.5. On this swede I got the M die set up so they would still chamber without removing the bell. The brass self centers for the most part. Bullets were seated out to engrave upon closing the bolt.
This rifle went from a turd to down right scary with the right guy on the trigger.
A fairly large bunch of folks go to a no turn spec Lapua reamer any more. The time and effort put into to turning has to be for love and nothing else.
I forget what wildcat I was working with years back. Almost had to ream first, and it still left enough meat to taylor to the chamber by turning. That was not an act of love, more stupidness than anything.
One of you gents will have to explain how reaming just moves the center line. And can still have an off centered neck. Ends up like not having your 4 jaw chuck dialed in right. You can still drill a round hole, just not dead center. If you want to pull hair out, expand your vocabulary and be prone to drinking heavily, get a cosintrisity set up.
To me bottom line is, the gun and everything that has to do with it, ALL of it has to have a great deal of promise to begin with. If it won't shoot 1" @100, neck turning ain't gonna help. Other things need to be tried, things need to be measured. However, Once everything has come together and it shoots bug holes, you can't wipe the grin off, nor can you buy that much satisfaction.
I have pounded tons of sand in rat holes over the years. Just as anything, "you don't end up with anything better than what you start with".
Jeff
KeithB
Resident Half Fast Machinist
I will offer a free opinion, which is worth exactly what you paid for it. It seems to me that when you are neck reaming, even when supported by a die or guide, you are still prone to shift the center of the new hole to the existing center of the hole. Reamers float and guides/bushings have to have some clearance to work at all. And when neck turning, the setups I've seen show the inside of the neck supported on a mandrel or spud and the OD is turned concentric to that. If the neck ID isn't centered up to the case OD then the neck isn't cut concentric. The outside of the case touches the chamber, the inside of the neck touches the bullet. Seems like what needs to happen is to use a single point tool to bore the neck ID while the case OD is held concentric.
Boring is one way to make a hole concentric and remove reamer deflection.
I am not speaking from shooting experience, just machining experience. Whether this makes any real difference is to be determined.
Boring is one way to make a hole concentric and remove reamer deflection.
I am not speaking from shooting experience, just machining experience. Whether this makes any real difference is to be determined.
Ian
Notorious member
When neck reaming on a typical case trimmer setup, the reamer turns and the case is held still. Same thing with the press-mounted reaming fixture. The reamer follows the existing hole. If it's off-center due to neck thickness irregularities, it will remain off center when reamed.
Outside turning makes the neck walls the same thickness. If the case is fired or resized, the OD will be concentric and the neck hole will be off-center. Outside turning makes the OD of the neck also off-center to match the ID. Fire-forming after making the neck thickness uniform will make a uniform, concentric neck...if the load was hot enough.
Outside turning makes the neck walls the same thickness. If the case is fired or resized, the OD will be concentric and the neck hole will be off-center. Outside turning makes the OD of the neck also off-center to match the ID. Fire-forming after making the neck thickness uniform will make a uniform, concentric neck...if the load was hot enough.