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View Full Version : Craters in boolit bases, how dose it affect accuracy?



Tripplebeards
10-13-2017, 08:06 PM
I casted up 10lbs of Lee 255g for my 45 colt yesterday. I made sure the bases were all flat and completely filled out. Most have a little crater where the spru plate cut the lead. How much, if any will this affect my accuracy out to, let's say a 100 yards, If the boolits weigh within a grain of each other? These are the first non GC boolit I've casted. In the past I can cover the imperfections with a GC and have shot almost MOA with Lee 300fn. Just wondering how this will affect my accuracy?

205792

vzerone
10-13-2017, 08:13 PM
That's a void. Sometimes they are hidden and just right beneath where the sprue is cut. they are in the center so then don't affect the accuracy that much. If more off to the side, then they would. Try pouring a more generous sprue puddle.

Tripplebeards
10-13-2017, 09:10 PM
I noticed when casting 35 rem today I tried to try and cut the sprue when the lead puddle just stArts to harden...hpjust hard enough to make sure it dosent smeAr. I casted tons of smooth bases today using this method. To bad I'll be covering them up with GCs. I also noticed the faster my Lee dropped lead the better the bases looked.

vzerone
10-13-2017, 10:00 PM
You should wait a tad longer for the sprue to harden. That will guarantee you don't smear the blocks and sprue plate. It won't tell the sprue out as much either.

runfiverun
10-14-2017, 01:04 AM
the two methods avoid the base tears.
smear or wait for the cut then deal with a bump.
there is a point in between the tear and the bump that will give a smooth base also.
I generally get a little tear because I run right on that side of the edge.

DSRichert
10-14-2017, 01:24 AM
Send half of them to me I'll test them for you

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Lloyd Smale
10-14-2017, 06:03 AM
like runfiverun said its a balancing act between cutting your spruce to hot and to cold. Accuracy wise id doubt it will effect a thing. Especially at the range most handguns are shot and hunted with. I used to cull every bullet that wasn't perfect. Ive got a buddy whos forgot more about handgun shooting and casting then I know that came over one day and looked at a pile of rejects. Some with bases slightly round some with lines in them from the mold being to cold and asked why the pile? I told him they were rejects. He said hed gladly take them and shoot them. He said even a terrible looking bullet doesn't shoot all that much worse at 50 yards. He said hes got one inch 50 yard groups from bullets worse then I was rejecting. I still do it. Call me a bit anal but I do save all the culls now and give them to him. Ive actually fooled around a bit since then and about came to the same conclusion. It takes a pretty nasty looking bullet to get 25 percent bigger groups and its only really noticeable in guns that shoot very small groups. If you take the average 1911, glock, sig ect that shoots 2-3 inch 25 yard groups you wont notice a thing shooting culls and a little flaw like you have there probably wouldn't be noticeable in even a rifle at a 100 yards.

buckshotshoey
10-14-2017, 07:55 AM
Even from a Ransom Rest, you will never be able to see a difference in grouping. Even if you could see a group difference, it means nothing unless you are competing where a cut ring makes a difference in score. They will only group worse if you think about it while shooting. Mind over matter. If you don't mind, IT WON'T MATTER.

I do cull some that I load, but only the ones that don't fill out properly (mold temp), and ones that are way outside the average weight of the batch.

KVO
10-14-2017, 09:49 AM
I have some molds that are worse then others about plucking out a crater or divot in the base. Some of the offending sprue plates benefited from gently sharpening the parting line with a countersink- seems every once in while they don't get cut to full depth. Also seems somewhat alloy dependent. I get worse base craters with high antimony/ low tin alloy. I'm with the majority opinion, doesn't cause near as much harm to accuracy as one would think.

KVO
10-14-2017, 09:51 AM
It's a custom feature: mini hollow base. ;-)

Tripplebeards
10-14-2017, 11:07 AM
like runfiverun said its a balancing act between cutting your spruce to hot and to cold. Accuracy wise id doubt it will effect a thing. Especially at the range most handguns are shot and hunted with. I used to cull every bullet that wasn't perfect. Ive got a buddy whos forgot more about handgun shooting and casting then I know that came over one day and looked at a pile of rejects. Some with bases slightly round some with lines in them from the mold being to cold and asked why the pile? I told him they were rejects. He said hed gladly take them and shoot them. He said even a terrible looking bullet doesn't shoot all that much worse at 50 yards. He said hes got one inch 50 yard groups from bullets worse then I was rejecting. I still do it. Call me a bit anal but I do save all the culls now and give them to him. Ive actually fooled around a bit since then and about came to the same conclusion. It takes a pretty nasty looking bullet to get 25 percent bigger groups and its only really noticeable in guns that shoot very small groups. If you take the average 1911, glock, sig ect that shoots 2-3 inch 25 yard groups you wont notice a thing shooting culls and a little flaw like you have there probably wouldn't be noticeable in even a rifle at a 100 yards.

I didn't think it would affect things much. My very first casts ( this year) came from the Lee 300fn. I had a lot of rounded bases. When I weighed them and matched them up within one grain of each other I was amazed on how many were perfect bases vs rounded with voids... And all close to the same weight. Well, after I PC them( the PC filled in some of the imperfections), sized and GCs installed I shot 100 yard groups as small as 1.1" in my 450 bushmaster. I made sure the bases were completely fill out with these. It helped tremendously with using a Lee 420 vs my stove to get the lead hotter. My camp stove heats it up great as well.

HATCH
10-14-2017, 11:14 AM
It depends on if the crater is formed because you didn't have enough lead on the sprue or if it was caused when you cut the sprue.
For pistol boolits, it will not matter much as a grain or two difference will have no major effect at the range that most pistols are shot.

Now on rifle boolits, it can make a difference.
When you reload you will get variances.
The boolits weigh slightly different. The powder may not all be the exact same weight, and even the case volume (thickness of case wall) will effect overall accuracy.
Some people are very anal about it and will weigh and measure everything by hand.
They will sort the cases by headstamp and year (if LC brass).
They will make sure the powder charge is the exact same charge as well as make sure all the powder is from the same jug/LOT.
This is the same for primers too. Same manufacturer lot.

John Boy
10-14-2017, 12:07 PM
Most have a little crater where the spru plate cut the lead.
Effect on accuracy at 100 yds = None
To resolve having 'creaters' in the bases:
* A 5 second ladle pour
* A good sprue puddle
* Wait for the sprue puddle to frost ... otherwise you a tearing the lead on the base that has not hardened
* Press down on the sprue plate when cutting the bullet

Wayne Smith
10-15-2017, 07:56 AM
Read "The Bullet's Flight" by Dr. Mann if you still think it will make any difference. He did the experiments back at the turn of the last century - and they have been repeated since by those who never read him!

25ring
10-15-2017, 08:03 AM
Effect on accuracy at 100 yds = None
To resolve having 'creaters' in the bases:
* A 5 second ladle pour
* A good sprue puddle
* Wait for the sprue puddle to frost ... otherwise you a tearing the lead on the base that has not hardened
* Press down on the sprue plate when cutting the bullet

Another option is to use a damp sponge on the sprue plate after it frosts over.It also speeds up your casting rate and less weight variance between bullets.

JBinMN
10-15-2017, 08:17 AM
"The Bullet's Flight" by Dr. Mann in PDF. form to read online/download if ya like.:

http://castpics.net/subsite2/ClassicWorks/The_bullet_s_flight_from_powder_to_targe.pdf

or

https://duienforcers.wildapricot.org/Resources/Documents/BulletsFlightPowderTarget_Mann_MunnCo_1909.pdf

--------------------------

Although fairly new to casting "boolits", I have usually been considering the "crater" a fault/imperfection if/when I get real deep ones & it goes in the reject pile.

This topic subject got me to thinking last night about something... I have on occasion, left something on the back bumper of my pickup trucks. Coffee mugs, partly filled beer/soda cans, hammers, etc. Many times, depending on time of travel & any bumps, I arrive at my destination with them still on the bumper. So, I started thinking about that & the craters in the bullets.

Seems to me that the airflow around the butt end of a bullet is like the back end of the truck. Flat, & the airflow meets further back behind & doesn't create enough effect on what is directly behind. Even a boat tail has a bit of a flat. Which reminds me of the wake of a boat which V-s out from the stern & has a "leeward" area behind the transom. Another example of how things directly behind something in motion that has a flat spot in the rear would not have much effect on the direction of the object.

Now, I am only going on observation & have not read that book yet.

But, just observation of other things I have seen makes me want to think that a slight crater in the base of a fired bullet should not have too much effect on the bullets path. ( I am thinking that,if anything, it is the difference in grains of weight between cratered & non cratered that may have an influence on accuracy.) Dunno... yet...
:???:

Now, I gotta go read some of that book.
;)

swheeler
10-16-2017, 11:17 PM
I like the Bruce B method, cast like crazy and when you start getting tears touch the sprue plate to a damp sponge, cut and move on. I cast about 900 45 230 grain after a half days work today, haven't sorted yet but bet less than 5 % will reject, if that. Don't worry about warpage, never experienced any aluminum or steel, think it's a myth. Tonight at about the 600 mark the left handle of my Lee six cavity handles slipped off over the quench bucket, reached in and grabbed the mold ASAP, pounded the handles back on, closed the mold and checked for light between halves, notta, cast 300 more. The wood handles are glued on with liquid nails projects adhesive now drying until tomorrows session. No need for tears.

beagle
10-18-2017, 12:10 AM
Those look like tears when the sprue was cut. Sometimes a void is right below it and visible. Leave a larger sprue and wait until it frosts before cutting and voids will be minimized at this point. ALL cast bullets have voids in them all over. I didn't believe this until Petey and I impact moly coated some .30s he cast with jewelers steel tumbling media. He was a careful caster and I'd say 80% of the bullets had voids. Nose, base, corners and bands. Some were really large and I'm surprised that cast bullets shoot as well as they do. The only way to completely eliminate voids is swaging a cast bullet with grease in grooves. This collapses all voids and gives you a consistent bullet...but, it takes a Swage-O-matic or other sizer and is a pain to do. Bullets processed in this manner are very consistent and accurate./beagle

Victor N TN
10-21-2017, 10:32 AM
My copy of Dr. Mann's book is stamped in the front, "Property of US Army Signal Corp." Before you say anything. I bought it through an online USED book seller. I taped the receipt and shipping paper inside the front cover.

Texas by God
10-23-2017, 11:28 AM
Void or not, those bullets look like candy to me. Very pretty.

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wv109323
10-23-2017, 09:38 PM
I am casting 200g. SWC to start loading for the winter. I shoot Bullseye pistol through the summer and then in the winter load what I will need for the next summer. I am currently casting my boolits.
I picked out 10 of the worst bullets I could find from my last casting session. I culled the obvious wrinkled boolits when the mold was getting up to temp. and the ones where the cavity was unfilled. The rounded bases and cratered bases were selected.
I loaded them and Ransom Rested them compared to a commercially cast 200 g SWC. The groups ended up the same size. The groups were 3" x 1 3/4" at fifty yards. One group was 3" Tall and the other was 3" wide. I could not tell any difference.

Tripplebeards
10-24-2017, 10:21 AM
Void or not, those bullets look like candy to me. Very pretty.

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They are for my dad. He wanted purple, so he got purple. The man is excited and wants some loaded for show and tell.