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milprileb
10-07-2011, 08:08 AM
Not to start a food fight on the subject but I got to ask for some experience from you guys on the subject.

I was under the impression nose first was the preferred sizing operation and that is why the Star is so prized as a tool. The Lee system allows one to nose size and its fast for my purposes. The Lyman 450 base sizes cast bullets and I don't see this method improving my accuracy.

I seem to get better pistol accuracy with nose first sizing.

I understand rifle bullet sizing base first might produce better bases and for long range accuracy, this is a big plus.

However, for 50 yd pistol 9mm and 45acp shooting accuracy, should I be seeing base first sizing as less optimum than nose first sizing of cast bullets.??

cbrick
10-07-2011, 08:20 AM
A flat bullet base (your bases are flat right?) against a flat punch will push the bullet through the die more concentrically. I proved this for myself several years a ago by comparing 7mm rifle bullets sized in Star, SAECO and RCBS sizers and examining them with a comparator. The difference was quite shocking.

It would make no difference being rifle or pistol bullets.

I did this test at a friends machine shop because some of the bullets sized on the SAECO were so far off center (not concentric) that looking from the nose down the side of the bullet with good light you could see a wide shoulder on the front driving band on one side and very narrow on the other side. It's been nose first sizing for me ever since.

Rick

Dave C.
10-07-2011, 08:33 AM
milprileb:

For handgun bullets at 50 yds you get the best accuracy from base first
sizing even with a Star sizer. I believe that when a bullet is sized the over sized
portion is swaged by the die. This material is pushed away from the end of the
bullet that entered the size die first. If you size nose first you may get small fins
forming on the edges of the bullet base. So size base first.

Distinguished, Master,2600 club, President 100 badge holder.

cbrick
10-07-2011, 08:51 AM
If you size nose first you may get small fins forming on the edges of the bullet base. So size base first.

Dang, how much are you sizing? Fins?

I've sized down far enough to reduce the size of the lube groove and don't get any fins on the base and I cast fairly soft by a lot of peoples standards. I do use a punch that fits to within a few thousands of the die diameter whenever possible.

A flat bullet base against a flat punch will size more concentrically than a poor fitting nose punch pushing the bullet into the die at an angle. Even a slight angle and the bullet is not concentric to it's center axis.

Rick

Dave C.
10-07-2011, 09:17 AM
cbrick:

Anything that improves the base of the bullet will make a difference
at 50yds. How much error is ok for you?

Dave C.

Distinguished, Master,2600 club, President 100 badge holder.

cbrick
10-07-2011, 09:30 AM
Error?

I'm pretty anal about my bullets and the base even more so, PB or GC.

50 yards is where I start shooting handgun and go out to 200.

Error? Fins? I just haven't experienced the problem you described.

BTW, how much off center, non-concentric is ok for you? If base first sizing makes you happy more power to you but there are other things to consider that the readers of this thread should be aware of.

Rick

williamwaco
10-07-2011, 10:12 AM
Don't know about comparators All I have is a good mike and microscope.
I use both Lee and Lyman 4500 dies.
I have fired at least 100 5 shot groups at 50 yards over the past year with my Thompson contender with 8x glass. I can see no difference in accuracy.
Some loads do better, some worse. Some bullets do better, some worse. I can see no difference in bullets Lee-ized vs bullets Lyman-ized.
I also cannot see any visible off centerdness in the Lyman-ized bullets.

As to swaging. I am running a test right now on bullet expansion after casting. The test includes 24, 158 grain .38 caliber SWCs. Some sized, some not. The sizing operation which was done nose first with the Lee die, as I expected, did increase the length of the bullet. The average increase for 12 bullets was 0.0033" this amounts to .47% in length.

GLynn41
10-07-2011, 10:55 AM
-Interesting thoughts -- I have tried nose first in Lyman 450 -- one thing I ran into and that stopped me from doing that was the top punch made a ring on the PB and thin Lyman .41 cal gc-- I am not trying to swage just nough pressure as needed--I cast mostly penta points and Keith HP from a mold Buckshot fixed up - they run around 11 BNH--not too soft but not real hard- I only have one cal. 41 so i do not change things ever-I did do as Veral suggested to help center the the TP -- I will look at nose first again

Larry Gibson
10-07-2011, 11:14 AM
A bullets base must be square to exit the muzzle evenly for best accuracy. If not gas exits unevenly causing wobble/yaw to the bullet. The less wobble/yaw the more accurate the bullet will be all other things being equal.

Base first through Lee dies does keep the bases of flat PB'd bullets squarer than sizing nose first. If the bullet has a meplat to sit on the flat ram it also keeps the bullet concentric to the sizing. Sizing nose first often results in small uneven rounded (sort of slightly "cupped") edges on the base of FB'd bullets. Perhaps not "fins" in the classic context but enough to many times adversely affect accuracy. This is particularly the case if sizing the bullet more than .001 - .002" or if the bullet is as cast out of round.

If seating/crimping GCs with a Lee sizer where minimal or no real sizing is done to the bullet pushing the bullets through base/GC first will seat the GCs better. The resistance of the GC to sizing causes the shank base to be seated to the bottom of the GC before crimping. Sometines this doesn't happen as well if the bullet is pushed nose first.

If the GC shank is over size to the inside GC dimension then seating the GC in a seperate operation will result in squarer bases.

Larry Gibson

Sonnypie
10-07-2011, 11:31 AM
Well now dang.
All my boolits have round bases.
How do you get a square based boolit down a round bore? :veryconfu

(Hey, you left the door open for that one.) :?

As you were. Carry on.

runfiverun
10-07-2011, 11:57 AM
seems as though the whole thing is about being off center and sizing too much.
airc rcbs and lyman both mentioned sizing, and how anything over .001 would deterioriate accuracy.
i'm still gonna size nose first.

Sonnypie
10-07-2011, 12:17 PM
seems as though the whole thing is about being off center and sizing too much.
airc rcbs and lyman both mentioned sizing, and how anything over .001 would deterioriate accuracy.
i'm still gonna size nose first.

(Whispering: I cast .309 and size to .308 for my 30 cal boolits. And size 452 for my 45 cal. and both nose first, Lee dies. But don't tell anybody, OK?) :-P

Larry Gibson
10-07-2011, 02:02 PM
Well now dang.
All my boolits have round bases.
How do you get a square based boolit down a round bore? :veryconfu

(Hey, you left the door open for that one.) :?

As you were. Carry on.

At ease, I'll be in the area for a while........

Just to not confuse those who might not understand your humor; the base of the bullet needs to be square to the axis of the bullet. If not, inaccuracy results from the uneven exit from the muzzle crown which should then be parallel to the square base of the bullet. So a "square" bullet into a round hole is indeed the most accurate......

Try sizing down .003 - .005 or more with a FB'd bullet pushed through nose first and then carefully inspect the base of the bullet. Use a magnifying glass and see if the bullet's edges aren't slightly and unevenly rounded over. It doesn't take much of that rolled over bullet base to cause wobble/yaw in the bullet on exit. Sizing nose first or base first isn't an "always" thing. Sometimes one is better than the other and sometimes it doesn't matter which way is used. I size lots of bullets nose first through Lee sizers, especially those that have a semblence of a BB and the sizing is less that .003". Like a lot of things we do with/to cast bullets there are a lot of "depends". Whether nose first or base first "depends"; I suggest the first "depends" is that many if not most shooters can't tell the difference in their shooting, especially with handguns even at 50 yards or less.

I suspect that Dave C is one of the rare few with handgun shooting ability to tell the difference.

I'd like to say that I am too but my time with a handgun shooting with such accuracy is past. My recent experience with which method is better comes from extensive testing of such sized bullets in scoped rifles. I can still shoot those with excellent accuracy. As an example take something simple like a Lee TL314-90-SWC loaded over 3.2 gr Bullseye in a .308W bolt action rifle. The bullets drop at .315- .316" from the 6 cavity mould. I do no "selection" other than toss one if wrinkled or the base is not filled out. I lube them with LLA and then size to .314 and then to .311 in Lee sizers to shoot in .30 cals. If I size them base first the bases stay nice and square and I can put 10, 20 or a 100 of them into 1.5" at 50 yards all day long with a sporter .308W rifle. However, if I size those same bullets nose first from .316 to .311 in the 2 sizings the bases are not square and they group into 2 -3" at 50 yards.

Conversely, in my 7.62x54R M39 and my 7.65 Argie (both with groove depths of .312" I can simply size the TL314-90-SWCs at .314 nose first or base first, load them over the same 3.2 gr Bullseye and they shoot just as well either way. That is but one example and I've seen the results with other bullets too many times to not pay attention to it. You, of course, are free to "carry on". :bigsmyl2:

Larry Gibson

Sonnypie
10-07-2011, 02:15 PM
Just funnin with you guys. :kidding:
I'm at that time in my life where going to the range makes me giddy. If I clang the steels, good for me.
If I miss I try another round, and/or adjust.
And right now I have to go load the truck. My shootin buddy will be here around 12:30, then we're off to the range for the rest of the day. He spots for me on the High Power range line, I help him reload the 22's on the steels range.
(He's 10)

Oh, and what about when a gas check goes on? Kinda changes things up there on the base, don't it?

(Ducks, runs...) :smile:

:lovebooli

plainsman456
10-07-2011, 03:05 PM
I have a star and a RCBS lube/sizer and the star seems to be faster after set up.
I do pistol and rifle in the RCBS and have been having some good targets show up more time than not.

Crawdaddy
10-07-2011, 03:54 PM
Just funnin with you guys. :kidding:
I'm at that time in my life where going to the range makes me giddy. If I clang the steels, good for me.
If I miss I try another round, and/or adjust.
And right now I have to go load the truck. My shootin buddy will be here around 12:30, then we're off to the range for the rest of the day. He spots for me on the High Power range line, I help him reload the 22's on the steels range.
(He's 10)

Oh, and what about when a gas check goes on? Kinda changes things up there on the base, don't it?

(Ducks, runs...) :smile:

:lovebooli


I enjoyed it! I was trying to count the yays vs nays and your post came along... Scratched my head for a minute. Keep it up.

Baron von Trollwhack
10-07-2011, 04:14 PM
You have to be open to sizing results when using ram & die type sizers. Sometimes with certain bullets, base first is best . I find that to be true with the minie' where the nose has a fairly large flat, the alloy is nearely pure lead and the sizing effort is more than moderate.

BvT

Bret4207
10-07-2011, 06:17 PM
I don't know that either method is usperior to the other given equal care and attention to detail. But I do know nose first seems to be easier for noobies to pick up and use sucessfully. I think the base first requires more care and fiddling to get exactly right.

williamwaco
10-07-2011, 06:31 PM
Try sizing down .003 - .005 or more with a FB'd bullet pushed through nose first and then carefully inspect the base of the bullet. Use a magnifying glass and see if the bullet's edges aren't slightly and unevenly rounded over.

. If I size them base first the bases stay nice and square and I can put 10, 20 or a 100 of them into 1.5" at 50 yards all day long with a sporter .308W rifle. However, if I size those same bullets nose first from .316 to .311 in the 2 sizings the bases are not square and they group into 2 -3" at 50 yards.


Larry Gibson



Larry,

You sound like you know whereof you speak.

Challenge accepted.

Can I see this effect with handgun bullets? Or do I need to use longer rifle bullets?

Using Lee push through dies, correct?

Char-Gar
10-07-2011, 06:37 PM
The answer to the original post is different, depending on the bullet.

Long rifle bullets can have their noses bent from the pressure on them, when they are sized base first. Hence, nose first is the way to go.

Hanned (before they went belly up) used to promote "coaxial" nose first sizing in a regular Lyman/Rcbs machine. This required a special taper on the inside of the sizing die, an ejector pin shaped to fit the nose of the bullet and a flat face base punch to push the bullet into the die.

But then, a nose first Lee type sizer works just as well and is quicker and cheaper.

Now when it comes to thick/fat handgun bullets, I don't think it makes a difference which way you do it.

Larry Gibson
10-07-2011, 07:46 PM
Larry,

You sound like you know whereof you speak.

Challenge accepted.

Can I see this effect with handgun bullets? Or do I need to use longer rifle bullets?

Using Lee push through dies, correct?

Yes you can see this effect with either handgun or rifle bullet as long as they are true flat PB'd bullets. The Lee push through are the easiest to use/test with. If you can try sizing in .001 - .002" increments upwards of .005 - .006" you will note the increasing base distortion, particularly around the edges. With BB'd bullets how much is discernable depends on the angle of the bevel.

My guess is that this same "nose first' sizing is why shooting cast bullets over .003" groove diameter is usually detrimental to accuracy. This is the case in .45 Colts where bullets are used in .455+ throats with barrel groove dimeter of .451. Also why cast bullets of .430 sizing shoot better in my Hawes .44 with a .429 groove diameter barrel and .435 cylinder throats. Bullets of .434/.435 shoot terribly but the .430 will shoot into 1.5 - 2" at 25 yards all day long. I know that disagrees with "fit is king" but that's the way it is.

Larry Gibson

rintinglen
10-08-2011, 12:59 AM
I ride with Larry on this one. I have an older Cramer 3 Cavity 148 WC mold that saw a lot of service in the late 70's while I was in my PPC stage. It casts pretty large. I had an old Lyman 45 modified to allow nose first sizing after pan lubing and was disappointed in the accuracy I was getting from my Python using them. An older competitor advised me size them base first and my groups got smaller and more consistent. A careful examination of the base showed exactly what has previously been described--a slightly uneven ring around the base of the boolit as the lead was squeezed and pushed back in the sizer die. Reversing the process made for better bases, and better scores.

MikeS
10-08-2011, 11:59 AM
Most of the talk about base first distorting the boolits is making 2 assumptions. First that a 'proper' nose punch was being used, and second that the sizer is misaligned. If sizing flap point boolits, and using a flat top punch (truly flat, not flat with sides) will eliminate any problem with misalignment. Most all the boolits I cast have a flat point, and I use a flat bolt (one of the ones Lee supplies with their bench plate mounting system) as a top punch, and so the boolits are always aligned with the sizing die. I also sometimes use Lee sizing dies, and have yet to see any distortion of the bases with them. I also have an old Lyman push thru sizer (designed for the 310 hand tool), and I was sizing some 38 caliber boolits nose first thru it, and the bases got distorted pretty badly. The distortion did seem to be pretty even around the base, so I'm not sure if it would make a difference. No matter how boolits are sized, my shooting won't be able to see the difference at this point in my life, as I have enough trouble with my hands that I can't shoot well enough to see a difference.

captaint
10-08-2011, 03:54 PM
Well hell, the reason I got a Star in the first place was because the boolits go in nose first. Just made sense to me. Who want to play with nose punches anyhow?? Just kiddin. Have it your way!! enjoy Mike

Echo
10-08-2011, 04:17 PM
milprileb:

For handgun bullets at 50 yds you get the best accuracy from base first
sizing even with a Star sizer. I believe that when a bullet is sized the over sized
portion is swaged by the die. This material is pushed away from the end of the
bullet that entered the size die first. If you size nose first you may get small fins
forming on the edges of the bullet base. So size base first.

Distinguished, Master,2600 club, President 100 badge holder.

+1, including the last line of the quote

turbo1889
10-08-2011, 09:11 PM
I use both Lee type push through press mounted sizers (not all are Lee but they all work that way) using primarily nose first but occasionally base first sizing and I have a heavily modified 450 that is capable of both nose first push through sizing, base first push through sizing, and base first return ejection sizing.

Long story short IME and IMH(BC)O the primary issue is not nose first or base first but rather centering and the reason many base first sizing operations get a bad reputation is not because base first is in and of itself inferior but rather that the nose punch is off center from the die and forcing the boolit into the die off kilter and off center. The best advise I can give you if you have a Lyman or RCBS unmodified, off the shelf lubra-sizer and are using it in the standard base first return ejection sizing mode is to get a length of 1/4Ē diameter rod and cut yourself an inch or so long length and use that as a universal flat faced nose punch and let the tip of the boolit ride up against that so it can self center and the nose isnít captured by the nose punch which is a situation where if the die and the nose punch arenít perfectly aligned it will force the boolit into the die off kilter and off center. Obviously, this works best with boolits that have a flat meplat to bear against the flat punch face but it doesnít work that bad on round nose boolits either and just leaves a small flat pressed into the nose which I like anyway. Unfortunately, pointy boolits are a no go, but it works great for everything else.

And if you need to size down a boolit anything more then about 0.002" then don't do that in the lubra-sizer die. Instead use a lubra-sizer die that is the same size as the boolit or just a thousandth of an inch or so smaller and just use the lubra-sizer to lube the boolit and then use a press mounted Lee type push through sizer die to size the boolit down with lube already in its grooves and size in several stages if you are sizing them down significantly.

BAGTIC
10-10-2011, 11:00 PM
I size all my bullets nose first. If I seat them in the cartridge case base forward they won't feed.