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odette
04-26-2018, 08:03 PM
I am casting with a new mold, it is a beautiful N.O.E. .358 Sil RCBS design and the bullets look fantastic. My question is about the bullet weights, they run from 181.7 gr to 183, with the bulk 182.3 to 182.7. What is the acceptable weight deviation? They all look good, just wondering if they are all keepers or not. This is my 1st experience with a more than 2 cavity mold and my 1st experience with an aluminum mold. All my other molds are 1 or 2 cavity steel. My 1st try last night was all wrinkled bullets and all rejects. Tonight I heated the mold with a hotplate while waiting for the lead to melt and I kept pot between 650 and 700 degrees. Bullets will be loaded in .357 Max and fired from a TC Contender 14" bbl, but 1st I will size, gascheck and powder coat. Any answers about what weight deviation I should consider as keepers would be appreciated.

sharps4590
04-27-2018, 07:22 AM
I suppose weight deviation is what a fella is willing to accept. For rifle bullets I like mine within 1/2 grain of each other. That amounts to a 1 grain spread. Probably not necessary to be that anal. I blame it on my Teutonic Sense of Order. I'd consider your weight difference good casting!!

DocSavage
04-28-2018, 11:42 AM
My cast bullets come I at .5 to 1% depending on caliber.

earlmck
04-28-2018, 11:45 AM
Dang fine job of casting odette. Them's keepers.

redhawk0
04-28-2018, 12:15 PM
For me...all would be keepers. Lately (yesterday) I've been casting 250gr .429s and 330gr HP .458s. I keep mine in a 2gr window and melt the rest. My alloy generally throws right at the "listed" weight. So I keep 248-250gr and 328-330gr....outside this range I recast. When I get heavier like my 405gr for the 45-70 I'll keep 402-405gr giving it a 3gr window. I'm like DocSavage...I try to keep what's in a .5-1% window.

Everything you listed...even the light's and heavy's....I'd keep.

redhawk

17nut
04-28-2018, 12:26 PM
Anything @1% is fine, unless you push the limit no need to go for .5% or better.

Kraschenbirn
04-28-2018, 12:27 PM
Those ought to be good in your .357 Max T/C. Years back, I shot the RCBS version of that boolit from a 10" .357 Contender in 'Hunter Pistol' silhouette matches for several years and don't recall ever bothering to weigh anything more than a random sampling now and then. You don't specify what alloy you're using but you might try upping your pot temp just a little bit...like 710-720...and, I suspect, you might find that weight variance significantly reduced.

Bill

quilbilly
04-28-2018, 12:34 PM
Anything @1% is fine, unless you push the limit no need to go for .5% or better.
I agree.

odette
04-28-2018, 05:49 PM
I wish I knew what the lead formula is. I inherited a Lyman Mag 20 that is 3/4 full of lead that had been melted, no idea what grandpa had in it. His small Lee pot appears to be soft lead. I used what was in the Lyman. I found buckets of small ingots of lead, some have an l on them, some an O, the rest unmarked. I think the O's might be wheel weights, the l is either Linotype or lead. I have a cousin married to a machinist that can test for hardness where he works.
I was sizing the little gems and am having a problem. I have a Lee turret press and using N.O.E. through sizing die set. My problem is some of the bullets get stuck in the sizing bushing and I have to take the bushing out and hammer the bullet out of it, ruining the bullet. I tried sizing without the gascheck and did not have any stuck, but some were tuff going. After sizing once, I put on the gascheck and ran them through again with no problem except for the gaschecks are dished instead of flat. Is this going to hurt. Are the bullets to hard to size? I am sizing them to .359 and I was planning on powder coating after gascheck.
I am 117 lbs so I put an extension on the reloader handle but am afraid of breaking the press or the bench. Anyone got any ideas?

Shiloh
04-28-2018, 06:10 PM
I just weighed 20 bullets from two batches cast from the same post. 175 gr .323 Mauser boolits. 1 1/2 grains between the two lots. Less than 1%
At 200 yards on q 13" gong, they work just fine from open iron sights.

If they have a decent fill and a good base, they get loaded and fired.

Shiloh

Kraschenbirn
04-28-2018, 06:17 PM
I'd say you really DO need to get those ingots (and whatever's in the pot) check for hardness. "...Get stuck in the sizing bushing" sounds like you may be casting from pure lino...or something awfully close. What do your unsized boolits measure? Your NOE mold is spec'd to cast .360 from straight COWW but could easily be dropping a little bit oversize and, with a really hard alloy might be a real PITA to size. Also, the cupping of the GCs tends to suggest that your boolits might be a tad oversize; i.e. the GCs aren't seating all the way onto the gascheck shank. Might be a matter of just cleaning a bit of flash off the base or it might be the shank is too large for the check to seat completely.

Remember, too, if you're planning to PC, you're gonna need to size those again 'cause the coating will add .002-.003 back onto the diameter and, if the boolit is already super hard, they may not go back through that Lee sizer die without scraping off some of the powdercoat.

Bill

odette
04-29-2018, 03:25 PM
measured before sizing at .361. I think I will size them 1st them put the gas checks on and lube them with liquid alox on this batch. I found some 7mm bullets that he had cast and they ring when I dropped them on the floor. I did see a suggestion about a fingernail test, tried that and didn't leave a mark on the bullets I cast.
Would it be better to melt them down and add more pure lead? I am hoping for a BH of 16 - 18 for Silhouette. I will take some of the bullets to a machinist friend that can get a true BH test on them.
If these are too hard will they even work on steel targets or will they simply shatter on impact?
Thank you for your ideas

Walter Laich
04-30-2018, 10:28 AM
also depends on your targets

in cowboy shooting we can shoot just about anything that comes out of the mold. Targets are big and close.

for long range work I would keep them much closer in weight

vzerone
04-30-2018, 10:39 AM
Like I mentioned in another post what you guys are casting is all well and fine for the shooting that you are doing. Just like the fellow mentioned about cowboy action shooting, the shooting is close and the targets are big. Now for those that want to get into the high velocity with accuracy game you have to have better bullets. A recent casting of 30 Sils gave me a .1 variance between bullets. I know a few casters that can do that. I believe the only way to do it too is with a ladle. With a ladle you have much more control over the flow pressure and volume then a bottom pour. I have a bottom pour too and I don't get that .1 variance with it. There is much more to it the filling the cavity. I'm not mocking any of you, I have done the same as all of you. All of us have. The fellow that does .5, that's not bad. Eventually I believe you can get even lower.

fredj338
04-30-2018, 03:44 PM
Lots of things affect final weight, but certainly mutli cav molds will throw more variation than a single or double. Larger the bullet the greater the variation. I rarely weigh bullets but for curiosity reasons, but find them reasonably uniform, +/- 1/2gr with the same alloy. I do weigh hunting bullets & anything that goes more than +/-1gr from average in 44/270gr goes to the practice box.

odette
05-02-2018, 11:36 AM
I did a pencil test on the bullets last night. Near as I can tell it took an H to slightly shave some lead and a 2H to definitely shave lead. I am guessing it is somewhere between 1:1 linotype , WW and quenched WW, monotype. So somewhere between BHN of 20 to 28. So I am guessing it is too hard to size and gas check without getting stuck in the N.O.E. sizing bushing. think I will melt the bullets down and add pure lead. There is approximately 11 pounds of hard lead, around BHN 24 - 25, will 4 - 5 lbs of pure lead bring it down to around BHN 14 - 15?
I was hoping to get an accurate hardness from my machinist friend but their test does Rockwell instead of Brinnell and he does not have the programing to do lead, it is set up for steel.