Confession, I'm an idiot!

[Boz330]

I got a Shiloh in 40-50 a week before deer season last fall. I did manage to get a deer, apparently out of shear luck.
Since then I have been tearing my hair out trying to get this gun to shoot, and there isn't much to spare anymore. I started with cut down 30-40 Krag cases which when you stuff a .409 bullet in them they are too big for the chamber and really rough to get in the gun. No problem I got a .410 neck reamer and reamed the cases so the bullets would go in and started working on a mid-range/silhouette load. At first this looked promising but soon went south quick and I was lucky to keep the rounds on a 4' by 4' target cardboard at 300yd let alone on the paper. I tried different boolits and no luck. This was quickly getting frustrating to say the least. I like to see at least a 2MOA or better group at that distance to make up for my 4MOA eyes.
I clean my cases using stainless steel pins and like them to look like new which with black powder takes longer than the 2 hours they recommend for smokeless. Anyway I ran across a thread here where a guy talked about the pins peening his case mouths and I got to thinking, usually a bad thing, but in this case an epiphany. My cases were peened to the inside and out. I was belling the case mouths to get the boolit to go in and then taper crimping the case so it would fit in the gun. This was actually digging the case mouth into the boolit and tearing lead off of the boolit, which is why some of the holes were indicating an unstable boolit and others not. Some of the cases were worse than others and I would have some sort of group but then all of these flyers that didn't make any sense, (10 shot groups).
Over the weekend I de-burred all of these cases and some of them had an internal burr big enough that I could hold the case vertical and the internal chamfering tool would hang on it with no support.
Yesterday I went out and shot at 125yd with some loads I put together after cleaning the cases up. I used the shorter distance to verify instead of having to run back and forth at the longer distance. None of the groups were completely terrible but one was 1 3/4" tall, which was absolutely the best I have gotten from this gun. Unfortunately by the time I got the cases cleaned up they were .015 to .025 shorter than optimal. I don't find this to be too much of a problem with GG boolits but it looks like some new cases in the future and all of the hassle to form them and ream them to spec.
This experiment has sure been an education and slow one at that. I thought that I had done a pretty good job at searching out the pit falls but apparently not. My old man always said that I had to go to the school of hard knocks for my education although I thought that I had outgrown that. On the other hand the fruit didn't fall far from the tree.
Hopefully this might help someone else out.

Bob

[Lead pot]

Bob I rate case prep 70% to get accuracy. Your lesson is well learned. As long as you found the error your not an idiot.

A case to long for the chamber with a tight hold on the bullet will pull the case up into the throat and do the same thing as not chamfering off the case mouth burrs. Inconsistent neck tension will give you a bunch of grief.

[Char-Gar]

Details of reloading aside, you most certainly ARE NOT an idiot! Idiots don't know they are idiots. You are just a guy on a learning curve. Nothing idiotic about that at all.

[Nueces]

Boz, your post adds to the considerable scholarship on this board. Thanks much for taking the time and thought.

I would like to address your having found online comments to the effect that SS pin tumbling peens or work hardens parts of the brass case. To those who arrive at such conclusions, I point out that the pins fall through a maximum distance of a few inches and through a water solution. Impact velocities are pitifully low. Consider that case to case impacts have to be much heavier than those with the little pins. No peening or work hardening is observed in any other tumbling process, all of which involve case to case impacts.

This idea of pins acting in any other way than gentle scrubbing is rubbish.

[Lead pot]

I think the peening starts from having them in a jug of water and shaking the geeewizzz out of them. Also chamfering the case mouth to sharp especially on a soft annealed case mouth.

I use pins as well as ceramic. A mix of the two in a very fast spimming Frankford Arsenal tumbler and a Tumblers Tumbler and a lot of times I have a hundred or more in the barrel and I have to say that I don't see peening or rolled in case mouth edges. But I don't anneal my brass but once when I get a new batch to get a proper fit to the chamber and from there on no more annealing or sizing.

I think most of the problems I see about peening starts from what I mentioned above. Rolled in case mouths starts with cases to long for the chamber. You need at least five thousands short of the chamber end to allow for movement to keep it from working up on the chamber end transition, the 45 degree most chambers have ahead of the throat.

[Boz330]

Boz, your post adds to the considerable scholarship on this board. Thanks much for taking the time and thought.

I would like to address your having found online comments to the effect that SS pin tumbling peens or work hardens parts of the brass case. To those who arrive at such conclusions, I point out that the pins fall through a maximum distance of a few inches and through a water solution. Impact velocities are pitifully low. Consider that case to case impacts have to be much heavier than those with the little pins. No peening or work hardening is observed in any other tumbling process, all of which involve case to case impacts.

This idea of pins acting in any other way than gentle scrubbing is rubbish.

You might have something there, since I've been tumbling mine for 24hrs in a Thumbler's HS tumbler. I sure never had the problem in a vibratory tumbler. Checked some of my other cases and they definitely have a lip as well.
These cases were formed from 30-40 Krag brass and cut short of 1.875 the case length. The cases were annealed prior to fire forming so they were soft. I normally anneal my cases once a year. These cases have multiple firings since I have been working on load development since last Dec. At least now I feel like I'm headed in the right direction. When you pay the price of a Shiloh and aren't getting anywhere close to expectation it is sure frustrating. I do this for fun but missing gets old pretty quick.

Bob

[Gunlaker]

I have two tumblers. The first I bought is a Lyman tumbler with a high RPM. It also has a really large diameter drum which causes the cases to fall further than other tumblers. It peens cases every single time.

I have Thumblers which is far better. It pretty much eliminated peening. I still check each case mouth at multiple locations with a sharp pick, but its rare that I find a peened case now.

I agree with the assessment that the peening is from cases impacting one another rather than from the pins themselves.

Chris.

[Chill Wills]

Details of reloading aside, you most certainly ARE NOT an idiot! Idiots don't know they are idiots. You are just a guy on a learning curve. Nothing idiotic about that at all.

Well said.
Bob, you are a good man and thanks for sharing your experience. We all are helped with the hard won knowledge of those who post.

[Dusty Ed]

I have thumblers tumbler an A few years ago they were yammering about only using half the ceramic an cutting back on the solution well I tried it an boy diid ever get peening, went back to full tub an stopped it