What is causing this? [Archive] - Glock Talk

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vafish
09-23-2011, 12:56
http://i109.photobucket.com/albums/n75/vafish/utf-8BSU1BRzA0NTkuanBn.jpg

Can't figure this one out.

Two rounds from my .25-223 wild cat. Loaded about 120 rounds up today, all but one look like the bottom one. The top one has that weird ring in the shoulder. I've had them occasionally do that (this is probably the third or fourth one in about 400 rounds) and they sure jam up the gun tight when the bolt tries to close. Thankfully it stops far enough out of battery that it won't fire.

I could tell that this one felt different as I was seating the bullet, just a little extra resistance in one spot when I pulled the lever.

Bullet is a Hornady 87 gr. spire point.

Here is the rifle:

http://i109.photobucket.com/albums/n75/vafish/utf-8BSU1BRzA0MjUuanBn.jpg

Made it for my 12 year old daughter to deer hunt with.

GioaJack
09-23-2011, 13:18
It's kind of hard to tell from the photo but it appears that you've had a partial neck collapse. This can be caused by several things, (debris clinging to the inside neck, old bullet sealant still in the neck, oversized bullet, fired powder residue, etc.)

Use a neck brush to clean prior to bullet seating, also the use of a lube, (a dry mica is the easiest since you don't have to remove it) prior to running the expanding button through it will also uniform your bullet seating.

It's also possible that you're getting occasional excessive bullet run-out while seating and the off-center seating is collapsing the neck.

Then again, your photo may not be showing what I think I'm seeing. :fred:


Jack

vafish
09-23-2011, 13:33
Makes sense, I use a spray lube when resizing the cases and clean it off with rubbing alcohol before I prime and finish loading them.

I thought I had tossed all my bad ones into my "to be pulled" bucket but I could only find this one and one other case. Both of them the head stamp says EB 223 556 and it looks like the primer was crimped in 3 places. So the possibility of some old primer sealant or something else catching on the flat base of the Hornady Spire point is pretty good.

Am I correct in thinking that there is no way to recover the case once the neck has started to collapse?

fredj338
09-23-2011, 13:37
Could also be the "donut", brass from inside the neck pushes out at the base of the neck. Happens when I form 260AI from 2433 cases. I have a 7TCU in a TC, good round. I always thought the AR platform would be better w/ a 24/223 or 25/223, maybe even 6.5x223. Nice, what vel are you getting?

vafish
09-23-2011, 13:45
With a 16" barrel I'm getting just shy of 2,600 fps. Usually around 2580 with the 87 or 90 gr bullets.

If you go up to a 20" or 24" barrel you supposedly can get 3,000 fps out of a 75 gr bullet equaling the original 250 savage load.

I built it because .223 is not legal for deer hunting here in VA. Went with the shorter barrel for my youngest to use.

fredj338
09-23-2011, 17:06
Very nice, should be quite effective @ that vel.

noylj
09-23-2011, 18:19
Did you ream the inside of the neck?
It is possible for a square-base bullet to occasionally catch the case wall and you end up shoving that side down.
You may need to chamfer the case mouth a bit more or you may find that a boat-tail bullet will load smoother.

PCJim
09-23-2011, 18:22
Another thought. The cases appear to be about same length as they lay side by side, maybe the top case is a hair longer? Any chance the top case had not been trimmed and that excessive length caused the shoulder to collapse during the bullet seating?

Can you provide the length of the two cases, not COL, but actual case length?

vafish
09-23-2011, 19:22
Cases were all trimmed before the first loading, this was the 2nd time they were loaded. I'll see if I get a chance to pull the bullets this weekend.

Case necks were not inside neck reamed.

I don't recall having this problem when I loaded the Sierra 90 gr Game King which is a boat tail bullet. I switched to the Hornaday because it was $4 a box cheaper and because Hornady technical folks replied back quickly when I asked them if this bullet would expand on deer at the velocities I am shooting them. Never heard back from Sierra when I e-mailed them the same question.