Home Forums Reloading Bullet Casting Bell Curves

Few days ago I cast some 311041 for the Sneezer and since I have in recent months been enslaved with the finer details, I decided to weigh them. Actual count was 199, so I came up short of the intended 200. Oh well, I can be short to on occasion.

Not to say I haven't paid attention to other bullet weights in the pastime, but I've mostly done this with bigger bore stuff loaded with Lord Black. About 5 years back I had an online discussion about weight variation for my .45-70 bullets and found I had insulted one of the members of that fraternity. I had a 3% spread in weight for 530 gr bullets and he opined that sucked. Said that .3 grains was an acceptable spread. None of the other disciples argued with him so I figured that was the Holy Grail.

So, today I weighed the 311041 lot. 199 bullets with an extreme spread of 2.7 grains. Now I had identified 5 bullets with minor inclusions and marked them for use as fouler rounds. I wound up with one lot of 50 bullets with a .2 grain spread. Another lot of 58 with no spread and a third lot of 57 with a .2 grain spread. 165 bullets total. in that group. Extremes of the curve were a 1.8 grain spread for 21 bullets on the low end and .2 grain spread for 13 bullets on the high end.

Now it is with anticipation that await finding out if this will make and difference. Started working with a change in primers a short time back that reduced velocity spreads over 50% for 5 round lots of ammo. Added a small charge increase and bumped up the velocity as well. A few days ago I shot a one hole group with the 311041 bullets at 50 yards that had not been weighed. Bit earlier I had fired a couple of groups like that with the old working load.



Any of you fellas fiddle with this stuff and if so, what have you discovered?

Or and I the King of all Loonies?

I started down your rabbit hole with a .38-55 heavy barrel single shot, and since I have the attention span of a third grader, I soon quit weighing and went back to bullet base inspection. I couldn't justify the labor and high rejection rate onto any big improvement on the target. But one mistake I made (of many probably) was shooting at 100 yds...should have reduced it to 50 to cut down on environmental factors. Another thing I haven't figured out...with the rifle nestled rock solid in a rest or bags, rear aperture centered, front aperture centered....just waiting and watching the sight picture, bingo...mirage...without the rifle moving the bull drifts out of alignment with the sights. In 600 yd high power competition we used to focus the spotting scope at 300 or so and glance in it when time permitted to "read" the mirage. On cold sunny days it could lose you a match. I never thought it could be a significant factor at 100 yds, but I suspect it is...at least enough to foul up bullet weight evaluation. So many questions. So many variables. I have pretty well satisfied myself though, that powder weight variations are low on the list of trouble makers. I'm all about measuring, now.

DD, I am curious about your primer change that cut velocity spread by 50%. Were you weighing powder to determine the primers were the cause, or using a powder measure? 5.2 grains of Blue Dot...seems any powder weight variance could cause the velocity spread, but then again, along with powder, bullet weight could cause it. But if you're sure of the primers, I would like to know which primer was better.

I shoot 100 and 200 yards, 200 grain in a 30BR. In testing powders using a chrony, when I shot and saw a low velocity in a string, the hit was always low. Don't take much.

Flintlocke is right too, base condition is huge at longer ranges.

Whole lot of variables in shooting cast.