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I just cast my first bullets in over 20 years. Some of the ugliest bullets I've ever cast. Just couldn't seem to get my temps regulated.... Recycled a lot. But, of the ones I kept, I weighed about 20 or so. Of a cast bullet at around 420 grains, what is an acceptable variance in grains, to give decent 100 yard accuracy in a 45-70 Marlin Guide Gun. I had an extreme of 3.0 grains, but most feel inside of about 1.5 to 1.8 grains. Thanks, memtb
3 grains out of 420 is less than 1%. If your Guide Gun isn't shooting well enough, look elsewhere for the problem.
Even +/- 5 grains would probably shot "decent" @100.
Targets or meat?
JSnover, Thanks, embarrassed to admit, but have had GG over a year and haven't fired a shot through it. Just started, today, casting for it and my 460 S&W. As I mentioned, bullets look like h&%l but, weights are fairly consistent. Years ago when I was casting, I didn't weigh anything. And they shot OK in rifles and handguns. Now, I'm trying to be more serious about quality control.... And they look like something from a bad "blind date"![smilie=b:. memtb
the mold might just need some time to get broke in.
quite often 4-5 heat cycles and a little patina in the cavity's smooth's things out.
you also just need to get a good rhythm going, the first few will be a different weight and if you let the pot come down to about 1/3 full or so you'll see another weight change.
the trick is to get in a smooth consistent rhythm and then just ride that out without letting the mold get too hot or go to the cold side.
then pick out the smooth shiny ones [from the start] and you are just looking for flaws after that.
"weight variance" --------------
Depends on what I'm doing/shooting.
For typical banger bullets in handguns, any reasonable bullet is going to do OK at living room distances. Looks OK, shoot it!
For increased distances, well it depends. At my handgun skill level for the most part there would be little to be gained!
For my 45/70, 465gr hunting bullets, I weigh them and most fall into one or the other of two, +/- .5 grain groups, but there are always that FEW that are for some reason surprisingly heavy or light.. so you could say that most of the bullets are within a 2 grain spread.
It is really fast with a digital scale to do this sort and while the bullets that fall within that 2 grain total spread are not likely to blow a group, the FEW that fall well out side that number Might!
So, I believe that weighing the bullets for this hunting rifle is worth the effort considering the small amount of time needed and my goal of using these bullets on deer and elk.
But, as indicated, the bulk of my casting is just sorted for defects and shot.
Now, I am in the process of developing cast bullet loads for a RUGER 77/44 with the goal of having a useable 100yd deer rifle. Hard to leave the 45/70 at home as it is AWESOME on deer and elk, but I'd like to take a critter with the .44. Therefore, I'll likely sort by weighing some of the 275gr cast bullets from the .444 mold that I'm also using in the .44. Won't take long and I'd hate to see a few minutes saved mean a missed or wounded deer.
But for the big picture I have had thousands of un-weighed cast bullet go down the tube and hope to cast and shoot a bunch more with the same result.
Crusty Deary Ol'Coot
I'm semi-retired and reload for rifle only. 7mm-08, 338 Federal the Lyman Sabot slug for my Remington 870. Just because I can I shoot for +/- .5 gr. for the rifles. Just because I can. The bullets for the 08 and the 338 will vary +/- 3 grains. I weigh and sort them out by the above criteria. I end up with batches of 4-5 weights for each rifle.
Overkill? Sure. But I have the time and I like controlling the variables. I take similar care in my powder loads.
Just my opinion but anything within + or - 2 1/2 grains of target weight for a bullet that size at 100 will shoot as good as you can hold or that the rifle can group with proper loading. A Marlin 45-70 with open sights is not a sniper round.
I do alot of competitive shooting. If I am shooting for score I typically weigh each bullet. I sort them from lightest to heaviest in sequential order. I will save them all but the ones that weigh the exact same that I have the most of will be used for the match. I then go back and load them in order of weight. This way, each shot never varies more than a tenth of a grain and usually a 10 shot screen will only have one or 2 tenths variance. Accuracy is all about consistency.
While some will say it's overkill, shooting is also psychological. The more confidence you have in your equipment/loads then that's one less thing you have to concern yourself with (i.e. excuses!)
Assuming a lack of visually apparent flaws, weigh them, sort them to +\- .3 grains lots, fire for effect. This standard works for ballpark 150-180 grain bullets Massage it for large or smaller bullets, just keep in mind the objective is consistency. You get to define your wants and needs.
First the disclaimer...
I cast with a ladle only... I do not own a bottom-pour pot, I've never used a bottom-pour pot. What I'm about to say is my assumption only, based on what I read in these sorts of threads about weight variances casting with a bottom-pour pot.
I believe you'll have significantly more consistent boolit weight casting with a ladle verses a bottom-pour pot. I never see any more than a ½ variance from average with 200-260 grain boolits casting with a ladle, with 95% or more of them coming within +/- .3 grains. My 150-200 boolits easily come within +/- .2 grains. I just recently cast some of the biggest boolit I've ever cast, Lyman 457122 330 grain hollow points... something around 100 of them. They came in a 335 grains, and the difference between the heaviest and lightest boolit of the batch was a mere .8 grains.
http://castboolits.gunloads.com/atta...1&d=1493837152
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Most, if not all, commercial cast 45-70 bullets CANNOT boast a 1 percent variation! Load em. Shoot em.
I shoot 45- 70 325gr cast. If they are within 3 or 4 grains, I will never notice the difference. And neither will the deer!