When neck turning what is the minimum neck wall thickness you should have? I am turning my necks and want to make sure that the necks are not to thin when I am done. I am only taking .002" off the neck which leaves me with .012" wall thickness. Any info would be good. Thanks
Neck turning
- Thread starter trda
- Start date
I just recently got into neck turning for my new rifle. Only because I had to.
I experimented with a few cases and found that if the walls were 7-8 thou in thickness.....you can squeeze the case mouth out of round with just your fingers. My guess is THATs too thin. 10-12 is about the norm.
I experimented with a few cases and found that if the walls were 7-8 thou in thickness.....you can squeeze the case mouth out of round with just your fingers. My guess is THATs too thin. 10-12 is about the norm.
I have not done any neck turning yet, but would think that you should only remove as much as needed to uniform the neck for the entire batch of brass you are using. My plan is to pick five pieces and set the tool to remove at least 75% on the worst one. From there cut them all the same amount and cull any that do not remove at least 75%. If too many are culled reset the tool and redo the batch.
As far as how thin is acceptable I do not know but I would think that if you are less than 10thou there are some serious problems with the brass and I would not use them.
Dave
As far as how thin is acceptable I do not know but I would think that if you are less than 10thou there are some serious problems with the brass and I would not use them.
Dave
I have just begun to neck turn my .204 Ruger brass. The Hornady brass that I have been using are actually pretty consistent concerning neck thickness. They average about 12 thou each with a max on some of 0.0135" and a min of 0.011" on others so I am pretty impressed with Hornady brass.
Seeing that I have a factory chamber I don't want to remove very much material so I have my neck turner set up to take it down to 0.012" and in most cases this removes material on about 25-50% of the neck area. Occasionally I will get a case that doesn't get any material removed so I check its thickness to be sure it is at least 0.011" (only one has been set aside so far out of the 150 done so far).
0.012" was a number I kept seeing when I was looking for advice on my .204, not sure if this applies to larger cases but its a place to start.
Seeing that I have a factory chamber I don't want to remove very much material so I have my neck turner set up to take it down to 0.012" and in most cases this removes material on about 25-50% of the neck area. Occasionally I will get a case that doesn't get any material removed so I check its thickness to be sure it is at least 0.011" (only one has been set aside so far out of the 150 done so far).
0.012" was a number I kept seeing when I was looking for advice on my .204, not sure if this applies to larger cases but its a place to start.
If you are going to turn brass on a standard chamber I would take off as little as possible.....only remove the high spots. I take 5-10 cases and start making the smallest cut possible on all of the cases with a final setting that removes an average cut of 50-75% of the case neck. Some of the cases will get a 100% cut and some will simply shave a few bumps off.
You want to be careful as removing too much can cause insufficient neck tension to hold your bullets with standard dies (this is why I like bushing dies). You also can create excessive neck clearance which is undesirable and could cause split necks.
Oddly enough the best and only accuracy improvement I have ever seen was on a custom built 338 Ultra with first production run brass (horrible). I saw an average improvement of 3/8" at 200 yards. FWIW the rifle is not normal and is capable of bugholes at 200yds.
You want to be careful as removing too much can cause insufficient neck tension to hold your bullets with standard dies (this is why I like bushing dies). You also can create excessive neck clearance which is undesirable and could cause split necks.
Oddly enough the best and only accuracy improvement I have ever seen was on a custom built 338 Ultra with first production run brass (horrible). I saw an average improvement of 3/8" at 200 yards. FWIW the rifle is not normal and is capable of bugholes at 200yds.
It depends on the dimensions of your chamber.
There is no point turning necks down to .012 if it will leave you with excessive chamber clearance. The whole point of turning that much is to conform to a minimum clearance chamber.
Typical neck wall thickness from the box is about 14 thou. If you turn it to 12 thou, you are now bullet+.012+.012. For example, a typical factory 6mm/243 would have a chamber neck of .275" .243+.012+.012= .267 This will leave you with 8 thou clearance. You typically want no more than 5 thou.
There is no point turning necks down to .012 if it will leave you with excessive chamber clearance. The whole point of turning that much is to conform to a minimum clearance chamber.
Typical neck wall thickness from the box is about 14 thou. If you turn it to 12 thou, you are now bullet+.012+.012. For example, a typical factory 6mm/243 would have a chamber neck of .275" .243+.012+.012= .267 This will leave you with 8 thou clearance. You typically want no more than 5 thou.
Personally
I would not waste my time turning necks on a factory chambered rifle.
I highly doubt you will see any difference by turning the necks. Yes you may get more consistent neck tension but that ends up being a waste if you are not using TOP QUALITY bushing dies.
I would not waste my time turning necks on a factory chambered rifle.
I highly doubt you will see any difference by turning the necks. Yes you may get more consistent neck tension but that ends up being a waste if you are not using TOP QUALITY bushing dies.
I turm mine like x-fan mentioned 50 to 75% remove all high spots, make sure to put case through neck die to keep case tight on mandrel of trimmer use a fine oil inside neck and outside.
Neck turning will improve accuracy even on a non custom gun like a Rem 700 or others
There are lots of fellows at range that shoot 1/2"+ groups with good non turned necks but few shoot 1/4" consistantly without neck turning.it helps.
Neck turning will improve accuracy even on a non custom gun like a Rem 700 or others
There are lots of fellows at range that shoot 1/2"+ groups with good non turned necks but few shoot 1/4" consistantly without neck turning.it helps.
The reason I am turning the necks is because I just had a barrel made and when it was chambered it was chambered tight. The smith is worried that if he tries to ream it out it may not ream straight. He suggested to turn the necks. I need to turn the necks so that I can chamber a round. I am not worried about excessive clearance as it is tight. Yes I am using Redding comp. bushing dies.
Man with redding bushing dies you might set a record for most reloadings from a case.your brass will hardly streach at all.Just get your self a Hart primer pocket swagger and Lapua brass you good for a lot of reloadings.
Have your gunsmith give you a chamber neck diameter.
Bench rest shooters seem to turn for between 1 to 1-1/2 thou clearance......If that is what you are doing?
This precision process is a total pain....My cutter will change .001 just by getting warm in my hands!
Ask your gunsmith for help and some relaxed clearances is my advice.
Bench rest shooters seem to turn for between 1 to 1-1/2 thou clearance......If that is what you are doing?
This precision process is a total pain....My cutter will change .001 just by getting warm in my hands!
Ask your gunsmith for help and some relaxed clearances is my advice.
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Like X-fan says for clearance but first you need to know exactly what size the chamber has been cut so you know what to have a loaded round at, if you go too tight when changing bullet brands you could end up to big this could be dangerous.
I do most of my tight necks about .002 my varmint hunting guns about .004
I know my 22 br's don't like them too tight they group better with about .002-.003
on the other hand my 6ppc likes .0015 when you find the sweet spot that is where it will shoot best.
also when you turn try and go up to the shoulder without shaving anything off this will avoid having to ream the inside of the neck to remove the dounut that will form when fireforming.
I do most of my tight necks about .002 my varmint hunting guns about .004
I know my 22 br's don't like them too tight they group better with about .002-.003
on the other hand my 6ppc likes .0015 when you find the sweet spot that is where it will shoot best.
also when you turn try and go up to the shoulder without shaving anything off this will avoid having to ream the inside of the neck to remove the dounut that will form when fireforming.
I am shooting a 7mm so Lapua brass is out of the question. I have the chamber size which is .307" so I am turning the necks so that they are .305" when loaded. This is leaving me with a wall thickness of .011". Time to start shooting and see what happens. Hopfully the walls are not to thin and the brass will last more than a couple reloads. Thanks for all the great info.
Be careful.
A 7mm with a .305 chamber is very tight necked, and your brass will all require more turning. (.284+.011+.011 = .306")
You should aim for about 2 thou clearance therefore... .305" - .002 = .303
.303 - .284 = .019 or in other words, brass that has a neck thickness of less that .010
A 7mm with a .305 chamber is very tight necked, and your brass will all require more turning. (.284+.011+.011 = .306")
You should aim for about 2 thou clearance therefore... .305" - .002 = .303
.303 - .284 = .019 or in other words, brass that has a neck thickness of less that .010
Back in the days before bushing dies were commonplace, one would turn the necks according to the die dimensions. The drill would go something like this:
1. Remove the expander ball
2. size case and measure the neck diameter of the sized case.
3. Run the case over the expander
4. turn expanded case neck to about .001 over the unexpanded sized diameter.
I used to turn necks for a 6x47 I had to give me about .0005 diametrical clearance. These cases did not require sizing but did have to be kept very clean. In general, I like to have at least .0015 radial clearance. Regards, Bill.
1. Remove the expander ball
2. size case and measure the neck diameter of the sized case.
3. Run the case over the expander
4. turn expanded case neck to about .001 over the unexpanded sized diameter.
I used to turn necks for a 6x47 I had to give me about .0005 diametrical clearance. These cases did not require sizing but did have to be kept very clean. In general, I like to have at least .0015 radial clearance. Regards, Bill.
