Author Topic: Crooked Bullets? (Read 468 times)

Propdoc03 · « **on:** January 04, 2004, 02:26:03 PM »

Well at the range today I had one out of four guns shoot. The one that did shoot was my .260 High Power rifle with open sights which always seems to shoot extremely well. One of the ones that let me down after a good day at the range last week was my model 7 .260. It has always seemed to be finicky and I thought I found the magic load last time at the range. I thought I had taken a bad measurement and was jamming them into the rifling and when I got home I re-checked myself and things measured fine. I decided to go ahead and seat them deeper anyway and today on about my third group the bolt was hard to close again. When I ejected the live round one side of the bullet was scuffed up. I rolled it across my bench and it had a very noticeable wobble, very noticeable! These were once fired cases and neck sized with an RCBS neck sizing die and seated with a standard RCBS die. I just got back from the range and got my guns cleaned and put up, but I was just curious as to if any of you have any thoughts on this? It did not look like the neck was the culprit? I almost ordered be a bullet spinner a couple of months ago and now wish I had of! For what its worth, my high power 260 was seated with the same die but was full length sized with the 107grn Sierra MK's. The Model Seven was loaded with the Hornady 129SST's and was seated half way then turned 180 degrees and then fully seated. When I get time I will do some experimenting with my dies, just thought I would run this past you for now.

Thanks PD

Propdoc03 · « **Reply #1 on:** January 04, 2004, 05:04:37 PM »

So I took my fired brass and neck sized it again. Seated three of the 129grn SST's. Once had a slightly noticeable wobble when rolling it across my loading bench and the other two were quite noticeable. I dont have an accurate way of measuring it but would guess several thousandths just above the ogdive and close to the nose. So I then took two 140grain Spire Points, one with a very slight wobble and the second had a quite noticeable wobble. I then took brand new brass didnt size it and seated two of the SST's both have a noticeable wobble. I honestly can not tell if the brass is banana shaped with the actual neck wobbling, though I dont see any gaps of light in the middle of the case when rolling it. I believe I can see the wobble starting just above the cannalure and that it where it was leaving a very obvious scuff\scrape on the bullet when it was chambered. I am now wondering if this is why my 260,s have been very finicky other than my High Power rifle. Even with this my little model Seven still was shooting at 1.25". Is there anything other than the die that can be causing this problem? I know I will be contacting RCBS and may ask for a return with an upgrade to Benchrest dies?

Thanks again,
PD

Propdoc03 · « **Reply #2 on:** January 05, 2004, 03:10:36 PM »

So I just got home from work and took my high tech
C-Clamps a piece of wood and a ruler and made myself a bullet spinner or whatever you want to call it. According to my dial indicator when set at the midpoint of the neck on a loaded round, I am just a hair short of .004 run out, might as well call it .005 as its so close. I didnt even bother to check the bullet as it is obviously going to be even worse. So is there anything other than the die that can cause this or is it a case of banana brass?

Thanks PD

jgalar · « **Reply #3 on:** January 05, 2004, 03:54:56 PM »

Do you have some crud in your seating die causing the bullets to cant while seating? Remove the seating stem and see if there are bullet boogers in it. Its hard to tell from your description if the brass appears out of round or just the bullet.

jgalar · « **Reply #4 on:** January 05, 2004, 03:58:31 PM »

Also check a fired case for runout before running it through the die - maybe your chamber is casing the runout.

Propdoc03 · « **Reply #5 on:** January 05, 2004, 04:52:41 PM »

So, I took five cases and did some measuring and this is the average of that I came up with.

Fired_____________________________.0013 runout.
Neck Sized-no expander_____________.0026
Neck Sized with expander____________.0027
Bullet Seated______________________.0035
Bullet Runout .035 above case mouth__.0046

I do not yet have the setup that I want and need for doing this but feel I am within +- .0005

PD