GCing, Sizing, and Neck Tension

[sundog]

I've been pondering this for quite awhile. If a boolit is the size you want, then checking and lubing in a die .001 (or more) larger will leave the check larger than the boolit and the boolit vitually untouched but nicely lubed. On loading the check will stretch the neck larger than the boolit. Most of my rifle rounds are not crimped as the tension seems to be tight enough to hold them (levers excluded). So, is there enough spring in the brass to create the necessary tension? What can this do to runout? Just thinking out load.... sundog

[felix]

Sundog, that's a good one. As much as anything else, I guess the only answer would be to let the gun decide. Faster powders tend to do better than slower powders in hiding these kinds of things from the accuracy equation. ... felix

[1Shirt]

Sundog, Good thoughts, and am inclined to think that Felix pretty much has it right. I shot my 77-44 yesterday with 250 Kieth PB sized 430, and was lucky to keep them in 6" at 50 yds. (Ya, crimped over the front band-lousy looking load). When I switch to 310GC Lee at .432, groups dropped to well under 3". In that case, both boolit and gc were well over what most consider to be appropriate dia. for 44Mag.
1shirt

[sundog]

Yea, and I'm also thinking that seating into the lands, standard for many cast loads in bolt guns, would also offset any detrimental effects, as long as run out is not a problem. sundog

[Shuz]

Corky, Funny you should mention this situation...yesterday I was trying some .311 diam 311291's in a .300 Sav case for my Rem 722. Never have tried this diam before in this gun. I discovered that the large boolit expanded the neck to the point that there was absolutely no neck tension left. Going to .309 boolits solved the problem. If I had a .310 boolit, I'da tried some of those, but I didn't have any ready.--Ray

[Bass Ackward]

I've been pondering this for quite awhile. If a boolit is the size you want, then checking and lubing in a die .001 (or more) larger will leave the check larger than the boolit and the boolit vitually untouched but nicely lubed. On loading the check will stretch the neck larger than the boolit. Most of my rifle rounds are not crimped as the tension seems to be tight enough to hold them (levers excluded). So, is there enough spring in the brass to create the necessary tension? What can this do to runout? Just thinking out load.... sundog


Corky,

You have just described my process 100%. Bullets are lubed and checked in one process and then sized nose first to prevent distortion and straighten the base. Runout is dependent on dies (seater cup) and brass more than sizing. And neck tension is imaterial if the bullet reaches the lands. That is because it let's go even before the bullet really starts to move in a lot of cases. Especially with faster powders. Sometimes this isn't the best for accuracy. But it works for me. :grin:

[imashooter2]

I experienced this problem in .30/30 for the first time using the new GB 311440 bullet. Sized in a .311 die, checks are .0015-.002 larger than bullet diameter. When seated, there is very little or no neck tension and even crimped bullets will push back into the case with moderate pressure against the edge of my bench. Bullets sized in a .309 die do not have this problem.

Guess I'm in the market for a .310 die...

[Bass Ackward]

I experienced this problem in .30/30 for the first time using the new GB 311440 bullet. Sized in a .311 die, checks are .0015-.002 larger than bullet diameter. When seated, there is very little or no neck tension and even crimped bullets will push back into the case with moderate pressure against the edge of my bench. Bullets sized in a .309 die do not have this problem.

Guess I'm in the market for a .310 die...


This is why I also use nose through sizers. Bullets come out one diameter if even gas check hardness is a slight problem. Much better than a librisizer sizing operation. And with lubrisizers you can have out of adjustment and bullet bending. (Key word there is "can".) Nose through eliminates all that as well as croocked gas checks.

[imashooter2]

This is why I also use nose through sizers. Bullets come out one diameter if even gas check hardness is a slight problem. Much better than a librisizer sizing operation. And with lubrisizers you can have out of adjustment and bullet bending. (Key word there is "can".) Nose through eliminates all that as well as croocked gas checks.


How does sizing nose first change the bullet to check size issue? I would think that pushing .310 diameter bullets and .3XX diameter checks through a .311 hole would result in .310 bullets and .311 or larger (springback) checks whether they went through nose or base first.

[StarMetal]

Horse hockey, funny how you fellows get sold on an idea altogether. First if you anneal your gaschecks they don't have a spring back, or not as much as unannealed. Horse hockey too on the luber/sizers are no good. Come on down to my house and get ready to lose your money. If you have a GOOD luber/sizer they work great. Mine happens to be a good one. I don't like the Lee nose first sizers because in alot of instances they screw up the gascheck so I end up sending them through base first. Mostly...I don't use them. Only one I have is for my 8x56R M95 Steyr because nobody else makes the proper size die.

I discovered checks being larger the the rest of the sized bullets when I was 5 yrs old. No, not really, but it was along time ago fellows. I even mentioned it on here along time ago.

Bottom line I'm really tired of hearing this crap that nose first dies are better then base first. You fellows go right on ahead and we'll see who shoots circles around whom.

Joe

[Bass Ackward]

How does sizing nose first change the bullet to check size issue? I would think that pushing .310 diameter bullets and .3XX diameter checks through a .311 hole would result in .310 bullets and .311 or larger (springback) checks whether they went through nose or base first.


Well now you have to make me think stop and think about how to answer that. And in truth, I can't explain it.

I never nose through size that I DON"T intend to size the entire bullet length. Maybe it's more because of the guidance of the rest of the bullet that I get a better fit? Or maybe it's just because of the second sizing step as opposed to the method? But it results in better diameters for me. Error rates are measured in .0001, not .001. To be fair though, I would have to reverse the process and see if results are comparable. Never thought about WHY before. But I have ran bullets up and down two or three times to fill all the grooves with lube and they still had larger bases unless I sized nose first.

Another thing I didn't mention is how the nose through sizer compresses lube more evenly into the grooves filling air space and removing the excess. This results in more evenly weighted bullets and cleaner seating dies.

You will read that many people weight their bullets before they lube. Well, this is a wasted step because they really need to be weighed AFTER they are lubed if you want to see accurate bullet variation. Bullets that carry more lube (wider grooves and larger calibers) exagurate the spread even more. I have seen better than a grain difference because of lube on a 45 caliber.

Most people never realize it. The check, the lube, it all contributes to bullet weight if that means anything. I have shot 35s with 5 grains different weight variation do to deformation into less than 3/4" on several occasions and have sence changed my "acceptance" standards for cast in some calibers if that is all I want.

[cbrick]

Very interesting thread.

Nose first is all I do with a Star sizer. Several years ago I took several bullets to a friends machine shop and checked them for concentricity. Half of the bullets were sized on a SAECO sizer and the rest on the Star. Looking at these bullets blown up to 50X was shocking. Differences on the Star bullets were measured in thenths and the SAECO bullets were measured in thousands. A few of the SAECO bullets were sized so far off center that there was almost no driving band left on one side.

Sizing and gas checking in one step and lubing in another is something that I have been doing for years and many thousands of rounds. Not in bottle neck cases though. I heat treat my revovler bullets for long range silhouette and this FA 357 shoots 192 gr bullets at 1550 fps into 2 1/2 inch groups at 150 meters (scoped from bench). Sizing 18 BHN bullets isn't much fun so I size, heat treat and then lube. Concentricity of loaded rounds isn't affected by this method but I use the Redding Competition Seating die and Redding Profile Crimp die.

[cbrick]

Going back to the Star / SAECO sizers, I bought my Star machine from John Adams when he retired after selling SAECO to Redding. hhmmm . . . why was the owner of SAECO using a Star machine ???

Rick

[MGySgt]

Bass - I have to dissagree on this one:

You will read that many people weight their bullets before they lube. Well, this is a wasted step because they really need to be weighed AFTER they are lubed if you want to see accurate bullet variation.

If the bullet is out of spec by weight before lubeing, after lubeing can mask that problem. So if you really want to get picky they should be weighed before and after!

Drew

[SharpsShooter]

Bass - I have to dissagree on this one:

You will read that many people weight their bullets before they lube. Well, this is a wasted step because they really need to be weighed AFTER they are lubed if you want to see accurate bullet variation.

If the bullet is out of spec by weight before lubeing, after lubeing can mask that problem. So if you really want to get picky they should be weighed before and after!

Drew


I weigh before lube. I don't see large numbers of boolits recovered that still have lube in the grooves. If it is still in the boolit, the lube is too hard for the application IMHO.

[sundog]

Yup, I weigh before lube, too. I'm lookin' for cullin' the light weights. Adding two more variables, a check and lube, only complicates that. sundog