Cast bullet accuracy

[Jim22]

Got my Lee Production pot up and running. Cast up some 158 gr and 200 gr 358 bullets. Some have flaws. I was wondering about how much weight deviation one could live with before accuracy went seriously south. Should they be sorted into groups according to weight? Should i only use the heaviest?

Anyone?

[M-Tecs]

That depends on application and usage. For applications like cowboy action I shoot a lot or reject bullets since they shoot well enough for that application. For 1,000 yard BPCR I weigh and inspect each bullet.

I don't have hard number or test results but if you are shooting at 50 feet you can get by with a lot of imperfections. The longer the distance imperfections become a much bigger issue.

[454PB]

The beauty of casting is that redoes of mistakes are easy. I reject any boolit that has a visible flaw.

[JonB_in_Glencoe]

I reject any boolit with flaws.
BUT, it may not matter. Years ago, I did a test with my Savage 340 222rem. I cast some NOE 22-55 (copy of the RCBS mold). I loaded the perfect looking boolits separate from a bunch of wrinkled boolits, all cast during the same casting session with the same alloy, they had GCs and TL'd with 45-45-10, and same load of powder, of course. Accuracy at 100 yds was the same.

[Jim22]

Here is what I have done: Got out my digital scale and weighed each boolit, then sorted them in rows of one grain weight increments. Tenths of grains were rounded up or down to nearest grain. I wound up, with the Lee 200 gr boolit, with a short row of 200's, Just a few 199's, a lot of both 198's and 197's. A few 196's. Separated them into labeled ziplok bags. That means all boolits in a bag are within one grain of each other. Anything less than 196 goes back in the pot. Sound about right?

[fredj338]

Here is what I have done: Got out my digital scale and weighed each boolit, then sorted them in rows of one grain weight increments. Tenths of grains were rounded up or down to nearest grain. I wound up, with the Lee 200 gr boolit, with a short row of 200's, Just a few 199's, a lot of both 198's and 197's. A few 196's. Separated them into labeled ziplok bags. That means all boolits in a bag are within one grain of each other. Anything less than 196 goes back in the pot. Sound about right?

Far too much work unless you are looking for best accuracy out ay 100y & beyond. For handguns, I just need a good base fill out. I dont weigh them. For rifles or hunting handguns going 100y & beyond I will weigh them to catch any potential internal voids. So +/- 2gr works for my 44mag & 45-70.

[Silvercreek Farmer]

Got any pics? If your mold/alloy is up to proper temperature you shouldn't get many (<1%) flawed boolits unless there is a venting problem with your mold or perhaps an ill fitting sprue plate.

[Jim22]

No pics yet. The 158 gr boolits are being used as-is. It's the 200 grainers I want to try in a Henry single shot rechambered to .357 MAX. The rifle will shoot MOA three shot groups with jacketed boolits but I want to see what it'll do with the 200 gr cast so I'm being exxtra picky. That's the gn I'd like to push the 200's to 2,000 fps if possible. My order of Carnauba Red arrived today so have lub/sized the 158's and am working my way through the 200's. This afternoon I intend to cast up a bunch more 200's.

[gwpercle]

If you are going to all the time and trouble to cast boolits ... then cast GOOD boolits .
Any visible flaw and any base that is not perfect ... toss it back into the pot .
Gary

[onelight]

If you are going to all the time and trouble to cast boolits ... then cast GOOD boolits .
Any visible flaw and any base that is not perfect ... toss it back into the pot .
Gary
I agree when I got free lead I cast for all my handgun shooting I have to buy it now if I am gonna shoot flawed bullets they will cheap commercial cast . My cast will be as good as I can make them and used for tasks other than my biweekly indoor range trips.

[wv109323]

I ran a test with a 1911 in a ransom rest. I cast a bunch of 200 SWC. I culled the obvious and then selected the worst looking I could find. These were bullets that I might reject after a closer inspection.
Loaded them up with the same recipe and used a commercial cast bullet for comparison. Both shot the same CTC distance at 50 yards, Both were 2 1/2" at 50 yards.
I think the bullet to bore fit and a flat bullet base are more critical for accuracy.

[M-Tecs]

If you are going to all the time and trouble to cast boolits ... then cast GOOD boolits .
Any visible flaw and any base that is not perfect ... toss it back into the pot .
Gary

And that is the real question. What is a good bullet? To me it is one that meets my performance expectations. Nothing more nothing less.

Some years I've cast as many as 40,000 bullets. If I used the same rejection criteria for all my cast as I do for my 1,000 yard competition bullets there aren't enough hours in a year to do that particularly when in some speed events like the local SASS matches the most challenging accuracy requirements is a 1/2 sized buffalo at 50 yards. Honestly if I could load rocks for SASS I would.

[DHDeal]

When a known good mold and alloy is at temperature and I have good base fill out, I'll have good bullets. I can weigh if I want but as long as the previous sentence is happening they'll be close enough for me, and I'm real picky. When I cut the sprue I'll look at all of the bases and if one isn't as perfect as the others, I'll push it into the sprue pan. Don't accept bad bases as it's too easy to just pour another mold full.

My opinion and what I do only.

[Wheelguns 1961]

Also, if you mix your alloy in your casting pot, it is important to thoroughly mix and flux before starting. I have found that this helps with consistent weights. For instance, I will put in half coww ingots, and half pure ingots, and mix good. When it gets up to temp, I will add my tin and flux, and mix real good. Then I am ready to start.

[dtknowles]

visible flaws might be a problem if you want less than 2 moa. Weight sorting is probably a waste of time at ranges less than 500 yards. I have weight sorted and also grade my bullets as #1's and#2's and shoot #2's for plinking. Can't tell that the #2's are any less accurate unless I am shooting bench rest groups at at least 100 yards. People talking about perfect bases are probably talking about plain base bullets. A slightly less than perfect base on a gas checked bullet will not be noticed.

Some people here would throw perfectly good bullets back into the pot and cast ingots from them. I would rather shoot them.

Tim

[charlie b]

I cast for my .308 mostly. I don't hunt, shoot paper for fun. Ranges are 100 to 600yd, mostly 200 and 300yd. I expect 1 1/2MOA as a minimum, with under MOA a goal for each of the bullets.

So, yes, I do find differences by weight. I sort to 1/2 grain and keep only those within 2gn of the heaviest. For example I have 210gn bullets in four boxes, 209.0-209.4, 209.5-209.9, 210.0-210.4 and 210.5-210.9

I have sorted to within 0.1gn before and have found no difference in accuracy. FWIW, I checked some commercial bullets. Sierra Match Kings 168gn were within 0.3gn. Hornady 168gn AMax were within 0.6gn (which is why I sort to 0.5gn batches now days). I only see a POI change at the longer ranges, >200yd.

I an not shooting that many bullets at a time (50-100) so I am a bit picky about fill out. I look for good fillout of the bands and base and no 'divots' in the noses. I count on the weight sorting to keep out bullets with obvious voids. If a plain base bullet the base needs to be perfect. It doesn't bother me to toss a bullet back in the pot.

OTOH, for pistols, I don't weigh them at all and will accept just about anything except a bad base. When I powder coat them they all look good :)

[Larry Gibson]

Jim22

It depends on the "accuracy" you are requiring or expecting.

Defects and/or weight variation does, in fact affect precision [inherent ability of the bullets to follow the same external flight path to the target]. The defect and/or weight variation induce imbalance in the bullet. How much that imbalance adversely affects the bullets flight depends on many variables; size of the imbalance, location within the bullet, RPM of the bullet and distance to the target. There are others but those are the major variables. The greater the imbalance in the bullet the larger the "group" [or effect the imbalance has on the bullets flight] will get in a non-linear rate of group expansion as the range increases. Fact is, the better balanced the bullet is on launch the more precise it will be at following the same flight path to the target as with other like bullets [same weight/no defects] forming a small "group".

How much defects and/or weight variations affect accuracy [ability to hit the intended target] depend not only on the above but what the group size is in relation to the target size at the range shot at but also the shooters ability to shoot "accurately". If shooting a load that groups 2 1/2" at 50 yards [that's 5 moa] from a rest that same load, discounting the non-linear expansion, would group about 1 1/4" at 25 yards and 5" groups at 100 yards. lets say, for S&Gs, that we take any shooter errors out of the equation. then hitting a standing beer/soda can at 25 yards is well within the imbalanced bullets capability. At 50 yards it is possible that one or two shots out of 10 shots might miss. At 100 yards given random dispersion of shots within a group it would be probable to miss the can 50+% of the time.

If target shooting for group size then eliminating all defects and weight variation as much as possible is tantamount to shooting small groups.

If target shooting for score then the same applies as a load that may barely hold 10 ring under the best of conditions will not be competitive. These days a load not X ring capable is not really competitive. Shooting cast bullets in such will require as perfect a bullet as you can cast.

In "fast" shooting competitions such as IPSC, IDPA, SASS, Steel Challenge etc. the targets are large, ranges short so the quality of the bullets isn't a deciding factor most often. In those games speed and accuracy in hitting a large target at relatively close range (not precision) are the most important. However, you can bet the farm that the consistent winners use good bullets without visible defects in them.

In your 1st post you say you are casting 358 bullets of 158 and 200 grain weights. Are you going to shoot them in rifle or pistol or both? What level of accuracy [group size or size of the targets and at what range] are you expecting or would like?

We see a lot of "accuracy" claims with such as "it hits a gong at 100 (200 or whatever range) most of the time"...... Sounds "accurate" right? Perhaps not though because I have 4", 10", 12' and 24" gongs and have seen a variety of other sizes at ranges ....so I wonder what size gong they are talking about? I also wonder when reading such just what "most of the time" actually means...... the point is "accuracy" has a lot of different meanings to a lot of different folks.

I have "blasted" a lot of non weighed cast bullets, some with minor defects [mostly just small wrinkles other than on the base] down range out of rifles and ore handguns that do not require a lot of precision over the years.....just for fun......and will continue to do so. However, with any serious cast bullet for informal target shooting, including handgun loads, or hunting I inspect each bullet during the sizing/lubing process and eliminate any with any visible defect. For serious target shooting or high velocity cast bullet rifle shooting I am pretty anal about inspecting and weight sorting to eliminate any defect or imbalance that I can. Doing so has proven, time and again, to be necessary for the absolute best precision and accuracy.

[marek313]

I would only separate by weight if I was shooting rifle over 100y and even then I'm not sure how much effect that would have. I know we have some people here that did test this. For pistol weight and small wrinkles dont mean much in terms of accuracy. Correct size, solid base and good barrel with generous throat and are all more important. I feel its a 50-50 and it takes both to get decent accuracy. 50% is bullet / powder / reloading procedures and the other 50% is barrel and throat. You wont shoot the most expensive ammo accurately out of bad quality barrel and the other way around. The most expensive barrels wont shoot well unless bullet has proper fit, shape, COL and are not swaged. Apparently it takes two to tango :D

[Goofy]

Some years ago I began fiddling with a modest cast bullet wildcat and as a result there was much learning along the way. One of the points went to bullet alloy, another to bullet design. Yet a third had to do with the topic of this thread.

The cartridge shoots a 180 grain lead bullet with target velocity of ~1,000 - 1,050 fps. I started out with 30:1 alloy and found as the loads were increased accuracy went south. No surprise there. I toughened up the ally a bit and things began to click. It started shooting 50 yard groups reminiscent of 20 yard targets.

On point of the discussion, I went out to do a bit of shooting awhile back and the target below shows how it went in clear terms. Top center target has a fouler shot that printed by itself. The next nine shots made a single hole. I was amazed, in part because I was shooting "culls", or bullets that had been set aside for purpose of loading foulers or for friends/family to shoot when they stopped by. My version of a fouler is one with any visible flaw, regardless of significance. When trying to work up a load I am as anal as anyone can be. The target on the left was shot with quality bullets and I suppose one could argue something like, "Hey, the group is less than half the size!" Well, yes, but is that because of fewer shots our the flaws in my culls? I dunno. One thing I know for a fact, I don't shoot pigs beyond 30-40 yards, usually a lot closer, and they would not know the difference.

https://i.imgur.com/0LR49yA.jpg

One another point, as mentioned above, distance of the shot is a player with such things.

Was fiddling around with some loads one day and shot the target below. 1 or two shots per target. Same loads at 100 yards print around 2.5" for 5 shots.

https://i.imgur.com/0euWqrn.jpg