Boolit Weight Differential - How Much Is Too Much?

[Foto Joe]

The mold is a Lyman 311041 casting COWW plus 2% tin. Pour temp (bottom pour) is approximately 725° to 750°. Here's my dilemma:

I'm shooting these out of a modern Henry H009B 30-30 at 100 yards using a Weaver 2.5 power scope in preparation for chasing Bambi this fall. I've got the load worked up currently at 20.0gr of 4198 and printing about a 6" group at the 100 yard range, good enough to hit dinner but I'm also a perfectionist. Keep in mind I'm not benching the gun but I am at rest so to speak, just not fully supported.

When I cast I'm getting boolit weights ranging from 173.0 to 174.6 grains. Anything below 173 gets recycled as there's usually a visible pin hole or a rounded base causing the light weight. Currently I'm separating the 173.0-173.9 into one pile and the 174.0+ into another and using them separately. My question is am I being overly anal about this? I understand that the light weight ones are a no-no because of possible voids etc. but is the +/-.8 grain (approx) THAT big of a deal or should I just cull out the light ones and have at it.

[IraqVet1982]

I did the math and 0.8gr over 173.8gr is less than a half percent. I bet your powder measure is throwing larger variances. At 100yds you won't see the difference.

[fastfire]

I separate my rifle boolits into 1/10th grain groups, that's proly a bit anal.
I do recycle the lighter ones.

[JSnover]

Is there a noticeable difference in group size between the lightweights and the heavies? I dont think that small variation is meaningful for 30-30 velocities @ 100 yards. Make sure everything on the rifle is tight and your dimensions are consistent.
Also pay attention to your dispersion. Horizontal or vertical stringing can tell you your position is not stable, breathing/cheek weld/support hand/firing grip is inconsistent...

[Foto Joe]

So far my groups are consistent in an approximate 4"-6" pattern, no vertical or horizontal stringing. My shooting position is sitting in a folding chair with the rifle rested over the bed of my Rhino. It's not the best but while hunting I doubt very much that I'll be able to get as good a rest as I'm using now. I tried to go out to the rifle range yesterday and use a real bench rest but our range didn't have any target stands and they want $10 a day for non members and I refuse to pay $10 and still have to bring my own target stand so I went to my normal area out on the other side of town.

[hickfu]

I was the same way with my boolits when I started casting.... My 430gr boolits were getting a 12 grain range out of a 5 cavity mold. I started separating them into 1gr increments and remelting ones that were too light or too heavy.... this was until I took them out and shot them at 100 yards with the same powder charge... I couldnt tell the difference, so I gave up separating them and only cull the ones that look bad.


Doc

[texassako]

I was the same way with my boolits when I started casting.... My 430gr boolits were getting a 12 grain range out of a 5 cavity mold. I started separating them into 1gr increments and remelting ones that were too light or too heavy.... this was until I took them out and shot them at 100 yards with the same powder charge... I couldnt tell the difference, so I gave up separating them and only cull the ones that look bad.


Doc

I did the same, but with some heavy .30 cals. I did not see a difference at 100 yards on the bench and just sort for visual defects now.

[JSnover]

Ask the folks in the Leverguns section. They've probably been through the same thing with your rifle/load.

[osteodoc08]

What does the gun slug at? Perhaps going up another thousandth in size will shrink your groups.

[Yodogsandman]

So far my groups are consistent in an approximate 4"-6" pattern, no vertical or horizontal stringing. My shooting position is sitting in a folding chair with the rifle rested over the bed of my Rhino.

Foto Joe, I used to use a folding chair and a folding ironing board with a couple of padded v-blocks of wood for a rest in a similar situation. Shooting off from old woods roads that I could find a good backstop. I got some great test groups using that's set up.

[Foto Joe]

Okay after reading the replies I think here's what's gonna happen. I'll continue to weigh for the light weight boolits, most that weigh out at below 173 have a visible pin hole somewhere or a rounded base. Other than that I'll dump all the +173's into the same box and gas check 'em.

As far as the groups are concerned I'm pretty happy with those considering how I'm shooting. I understand that lever guns are NOT bolt action match guns and at least for me with a 2.5 power scope I'd say that 6" at 100 yards is pretty good.

[pls1911]

I cast and load the 311041, Ranch Dog 311-165, SAECO #315 (160 GRAIN) and RCBS 165-SIL.
I sort into groups +/- .5 grains... yep, I'm anal about consistency.
However, +/- one grain should not be noticeable.
I don't adjust sights between any of the bullets listed above, and at the same velocity (1800-1900 fps) there's no practical difference in accuracy or point of aim at 100 yards.

The results are one hole/one inch at 30 yards and always minute of pig or less out to 100....I don't really know, but I don't normally miss either...I'm anal about shot placement too, and don't shoot unless I'm sure of a DRT.

[Foto Joe]

I cast and load the 311041

Just out of curiosity, what's your pet load for the 311041?

[Le Loup Solitaire]

A variance of 2 grains in the 311291 or the 311041 at 100 yards or so will not make much of a difference in the grouping for hunting purposes, but you still need to go through the bullets and screen out those that are either lighter or heavier than the 173-175 range. Of more concern is your mention of pin-holes in the bases which is usually a sign of voids/hidden holes below the base surface....those voids can be, and usually are.....off center and cause a weight imbalance in the slug that will start its bad act when the bullet leaves the muzzle, and you will get wild shooting from it. Suggest that you pour a generous sprue puddle to allow the alloy to get pulled into the cast as it shrinks; that should help if not cure the problem. I too use an old ironing board as a shooting bench...with a bit of padding it does very well....certainly better than crazy range fees, etc. Good shooting and hunting. LLS

[Foto Joe]

Interestingly enough, the pinholes are rarely if ever in the base. About half the time on a light boolit I'll find a pin hole in one of the lube grooves for some reason, very small and almost undetectable, this is the reason I started weighing in the first place. I figure that if there's a pin hole in a lube groove then I definitely have an out of balance boolit.

BTW, if I brought home an ironing board I'm afraid my wife would beat me to death with it.

[725]

Just a thought: You've mentioned round bases a couple of times. Happens to all of us from time to time. Just a bad example. Have you thought about increasing the pot temp/mould temp? I ladle pour and let the silver stream overflow and run back into the pot off my sprue plate. This ensures a hot sprue plate and gives me nice square - flat bases. The closer to a perfect base I can get, the better. I rarely get those partial fill-outs or pin holes.

[Foto Joe]

Any rounded bases are a matter of an operator error I'm afraid, such as a spill over into the second hole before I actually moved over to it (bottom pour 725°-750°). Rounded bases are few and far between.

The light weight boolits aren't really a problem as they represent probably around 5% of those cast, I can live with that. My main concern was that the +/- 1 grain would throw off groups. After reading the above posts I don't think I'm going to worry about it and just weigh out to eliminate the light ones.

[GhostHawk]

My last batch I went through each bullet with a new digital scale. The new scale made it dead easy, set a bullet on, wait half a second for it to get a reading, pull the bullet off put it one of 5 piles, grab the next.

Out of 100, there were 2 that were more than 1 grain from average.

It really sorted itself out into 3 main groups. .3 grains up or down from center. This is the biggest group, 60% The next biggest group would be those .4 to .7 heavier than average. The last group being the light ones and as I mentioned only 2 significantly out of range.

So I proceeded to size, gas check, then lubed and sized again. I'm back weighing after the last sizing and I'm going ***!

The light bullets got heavier with gas checks and lube, and some of the heavy bullets were now in the light group.

Turned off scale, screw this @#$% it isn't worth the bother! They're close enough!

Sure they may weigh near 195 instead of 185 but they still shoot brother. So quit driving yourself crazy!

Your mileage of course may vary.

I do have to say that if I was hand loading for a competition, I would weigh and group boolits.

[GhostHawk]

My last batch I went through each bullet with a new digital scale. The new scale made it dead easy, set a bullet on, wait half a second for it to get a reading, pull the bullet off put it one of 5 piles, grab the next.

Out of 100, there were 2 that were more than 1 grain from average.

It really sorted itself out into 3 main groups. .3 grains up or down from center. This is the biggest group, 60% The next biggest group would be those .4 to .7 heavier than average. The last group being the light ones and as I mentioned only 2 significantly out of range.

So I proceeded to size, gas check, then lubed and sized again. I'm back weighing after the last sizing and I'm going ***!

The light bullets got heavier with gas checks and lube, and some of the heavy bullets were now in the light group.

Turned off scale, screw this @#$% it isn't worth the bother! They're close enough!

Sure they may weigh near 186 instead of 185 but they still shoot brother. So quit driving yourself crazy!

Your mileage of course may vary.

I do have to say that if I was hand loading for a competition, I would weigh and group boolits.

[MostlyLeverGuns]

Unlike bolt-guns, leverguns are VERY SENSITIVE to how they are rested and/or held. Many two piece stocked rifles are. Where you rest the forearm, how tight you hold, the hardness of your front and rear supports can all make a difference. For load development you should strive to narrow variables so that differences in powder, charge weights , and other loading variables can be recognized. Shooting six inch groups offhand is excellent for hunting. Most 'modern' leverguns in decent shape, 94's, 336's, 99's and similar will stay inside 3" at 100 yards WITH cast bullets 'off the bench'. Most will do better with a little care, but holding technique is important. I found a couple of sandbags on a blanket on the hood of a pickup, leaning against the fender worked very well if a benchrest is not available. A folded towel over my shoulder keeps the recoil from bothering me. Spending time getting comfortable behind a rifle can shrink groups remarkably.

[BruceB]

^^^^^^ This post from Ghosthawk describes my findings as well.

In actual, repeated test weighings of large batches of bullets, more were rejected for VISUAL flaws than weight variations..... that is, some bullets that passed the weight sorting were NOT acceptable due to obvious "eyeball" faults. The opposite was not true.... no bullets that had a perfect appearance failed the weight test.

I no longer bother to weigh batches of bullets..... if they LOOK good, they ARE good. If competition could be involved, I too would probably check-weigh the bullets "just in case".... but experience with bullet batches and the electronic scales tells me it's not really necessary.