Re-turning necks
- Thread starter Vern
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Stephen Perry
New member
Vern
Turning case necks is one thing I do often and do well. When setting up for a fitted neck pin gauge the chamber neck. I always like to know the 4th number. Life is not always a .262 reamer cut neck actually the 4th number of the cut neck is some other number than 0. Example a reamer might cut a .2622 chamber neck. Another reamer might cut a .2628 chamber neck. they are both called a .262 chamber neck by the generic benchrest crowd but not by the smiths, smiths are not generic they are individuals. Hey I want to know the .0006 difference so when I set up for a tight neck load I ain't on the edge of blown brass and headaches from extraction. I would say Vern if you load a tight neck load you should skim/ whisker cut when needed to maintain the tolerances, So Vern no every 5 shots skim cut when needed this could be after 2 shots for a tight neck load, measure.
Makes no difference which turner you have most always cut the same, depends on the mandrel and the squareness of the cut. Actually Vern if don't change the setting on you cutting blade you can come back time after time using the same settings on your turner and skim/whisker cut. For turners I have a Marquart, Jaco, Miller, and several Nielsons. Which do I like the best I like the Marquart, easy to use but you need a smith to cut some tight mandrels so as to get the full effect of the re-cut. Actually my Harvey Miller turner is my favorite Harvey used elliptical mandrels for my 22 and 6 cases. You can sneek up on a mesurement wih the ellipticals. Nielson and Jaco are as precise as NASA, but do you need this for benchrest, maybe especially for a fitted/tight neck. Vern if you go fitted /tight neck cases it's high maintenace. Most BR shooters set up for what they think is .002 clearance between chamber cut neck, low maintenace, and loaded case neck. But these shooters are generaliazing, their measurements when they say well my reamer cut a .262 neck is a guess, but is the reamer cutting a .2622 neck or a .2628 neck need to pin gauge to know for sure. One last item. OK, same reamer. 2 different barrels. Different stainless from lot to lot. Different smith same reamer same lathe different set up depending on smiths desires. Each smith cuts a different neck depending time of day, temp, attitude of smith, what one smith calls done and the next says not yet. Point is Vern wouldn't hurt for you or any shooter to know the 4th number in a chamber neck. Pin gauges are easy to come by, not expensive. For a .262 chamber neck have 10 - 15 from say .2618 to .2632 for a so called .262 cut neck. Keep trying them the one that is snug but slides in out without a big effort is your 4 th number. I learned this from my smith I never forget important stuff when it comes to benchrest. Vern you need to know the 4th number in a chamber neck to be able to turn for a tight/fitted neck. Vern you ever noticed old guy shooters rubbing their case necks with steel wool or fine sandpaper. Chances re they are not just cleaning necks. They are also taking off a smidggin of their case necks because with a tight neck say .2624 chamber neck and a .2622 seated bullet neck the smart old guy benchrest shooter knows he needs to recut but he's in the middle of an agg and the fine sandpaper will give him the tolerance to shoot a safe functoning BR load. But eventually the sandpaper trick won't keep working and a re-cut becomes necessary to get back to his starting .2622 seated bullet dia.
I don't recommend a tight fitted neck for those that don't understand the concept and will not maintain the tolerances when needed.
Done.
Stephen Perry
Angeles BR
Turning case necks is one thing I do often and do well. When setting up for a fitted neck pin gauge the chamber neck. I always like to know the 4th number. Life is not always a .262 reamer cut neck actually the 4th number of the cut neck is some other number than 0. Example a reamer might cut a .2622 chamber neck. Another reamer might cut a .2628 chamber neck. they are both called a .262 chamber neck by the generic benchrest crowd but not by the smiths, smiths are not generic they are individuals. Hey I want to know the .0006 difference so when I set up for a tight neck load I ain't on the edge of blown brass and headaches from extraction. I would say Vern if you load a tight neck load you should skim/ whisker cut when needed to maintain the tolerances, So Vern no every 5 shots skim cut when needed this could be after 2 shots for a tight neck load, measure.
Makes no difference which turner you have most always cut the same, depends on the mandrel and the squareness of the cut. Actually Vern if don't change the setting on you cutting blade you can come back time after time using the same settings on your turner and skim/whisker cut. For turners I have a Marquart, Jaco, Miller, and several Nielsons. Which do I like the best I like the Marquart, easy to use but you need a smith to cut some tight mandrels so as to get the full effect of the re-cut. Actually my Harvey Miller turner is my favorite Harvey used elliptical mandrels for my 22 and 6 cases. You can sneek up on a mesurement wih the ellipticals. Nielson and Jaco are as precise as NASA, but do you need this for benchrest, maybe especially for a fitted/tight neck. Vern if you go fitted /tight neck cases it's high maintenace. Most BR shooters set up for what they think is .002 clearance between chamber cut neck, low maintenace, and loaded case neck. But these shooters are generaliazing, their measurements when they say well my reamer cut a .262 neck is a guess, but is the reamer cutting a .2622 neck or a .2628 neck need to pin gauge to know for sure. One last item. OK, same reamer. 2 different barrels. Different stainless from lot to lot. Different smith same reamer same lathe different set up depending on smiths desires. Each smith cuts a different neck depending time of day, temp, attitude of smith, what one smith calls done and the next says not yet. Point is Vern wouldn't hurt for you or any shooter to know the 4th number in a chamber neck. Pin gauges are easy to come by, not expensive. For a .262 chamber neck have 10 - 15 from say .2618 to .2632 for a so called .262 cut neck. Keep trying them the one that is snug but slides in out without a big effort is your 4 th number. I learned this from my smith I never forget important stuff when it comes to benchrest. Vern you need to know the 4th number in a chamber neck to be able to turn for a tight/fitted neck. Vern you ever noticed old guy shooters rubbing their case necks with steel wool or fine sandpaper. Chances re they are not just cleaning necks. They are also taking off a smidggin of their case necks because with a tight neck say .2624 chamber neck and a .2622 seated bullet neck the smart old guy benchrest shooter knows he needs to recut but he's in the middle of an agg and the fine sandpaper will give him the tolerance to shoot a safe functoning BR load. But eventually the sandpaper trick won't keep working and a re-cut becomes necessary to get back to his starting .2622 seated bullet dia.
I don't recommend a tight fitted neck for those that don't understand the concept and will not maintain the tolerances when needed.
Done.
Stephen Perry
Angeles BR
Last edited:
Any amount of clearance is enough if maintained. Cut enough clearance that you don't have to watch it constantly nor concern yourself over a re-turn. This is not a critical dimension in the accuracy equation.....Alinwa may disagree....
Cerrosafe is a great method.
Case life is dependent on the powder drop setting and how far you are willing to push 'em. I know folks that will start new cases at the first sign of a loose primer where as I'll use them until there's no place left to put a primer. I've no proof, but I believe I'm goofin' up by doing that.
Cerrosafe is a great method.
Case life is dependent on the powder drop setting and how far you are willing to push 'em. I know folks that will start new cases at the first sign of a loose primer where as I'll use them until there's no place left to put a primer. I've no proof, but I believe I'm goofin' up by doing that.
Vern
Morethan1waytoskinacat
Thanks
I turn the original case to have about .002 clearance but I just wanted to make sure after repeated firings whether it would be necessary to maintain run out or clearence.
Didnt know if it would be necessary to return them just for accuracy sake but it sounds like as long as I have clearance that I am good.
I suppose I can check the run out on my gauge.
I turn the original case to have about .002 clearance but I just wanted to make sure after repeated firings whether it would be necessary to maintain run out or clearence.
Didnt know if it would be necessary to return them just for accuracy sake but it sounds like as long as I have clearance that I am good.
I suppose I can check the run out on my gauge.
On those days when things are not going your way (aka - groups too big), you can run a quick "neck check" with calipers and use that runout guage. Thing is, those measurements will be the same as on the good days. The reason to do that is to give you something to occupy your mind until it's over.
Nothing makes a good rifle go bad faster than necks that are too long. Keep a regular check on that dimension.
Nothing makes a good rifle go bad faster than necks that are too long. Keep a regular check on that dimension.
C
Cheechako
Guest
Just to satisfy my own curiosity I shot a 6PPC barrel for one entire season with the same set of cases. I started with 25 cases and ended with 19. Total shot count was right about 1500 so you can figure for yourself how many times each case was fired. I never once annealed, inside reamed, or re-turned the necks. I started out checking case length after each match but I even stopped doing that after a couple of months. I won my usual share (not many) of fake wood trophies.
Of course, I necked size only and used moderate loads (3200 fps). The only reason I discarded them was because I told Skip Otto what I had done and he wouldn't leave me alone until I tossed them.
Ray
Of course, I necked size only and used moderate loads (3200 fps). The only reason I discarded them was because I told Skip Otto what I had done and he wouldn't leave me alone until I tossed them.
Ray