Have any of you seen this before?

[Shootist43]

I purchased a Winchester Mod. 70 African Express in 375 H&H off Gunbroker a little over a year ago. It sat in the safe till recently. A couple of weeks ago I loaded up 10 rounds using new Norma brass and 300 Gr. Hornady DGX bullets (for cheap practice only). I bore sighted the gun at 25 yds. The scope is a 1.5-5 Leupold VX-3. To put it mildly, the groups were terrible. At first I thought it was me or something I was doing wrong, you know, the don't blame your tool sort of thing. I started to reload the once fired cases when I noticed something peculiar. On every piece of brass there was an indentation about 1/8th inch down from the mouth that is about 1/8" wide. Take a look at the attached photos. My question is what could have caused this and can it be corrected?

 

[Ridgewalker]

Do you have a bore scope?
Was there any insertion issues or extraction issues?
It might be a ring of brass left in the chamber neck from a worn out brass, ie reloaded to many times. If so, try using a short pistol or chamber rod with a bronze 375 brush. Use Soak the chamber first with a good penetrating lubricant. Insert it just into the neck. Rotate it and pull it back out. Hopefully, if it is a brass ring, it will come out.

I had a 22-250 in Rem 700 which something similar happened from not annealing or work hardening a case too much, but I couldn’t insert a new cartridge.
Best of luck finding the problem!

 

[Shootist43]

A buddy of mine had a couple of cheap Chinese cameras on a wire that we inserted. We could see something but the image wasn't very clear. I don't have access to a Hawkeye borescope. I like your idea though. I didn't have any trouble or adverse indications while inserting live rounds or extracting empty shells. The photos shown are of the cases after they were resized. My bad for not seeing the issue sooner.

 

[tarbe]

It would be interesting to see a profile of the diameters of that neck from shoulder to mouth - as they come out of the rifle, post firing.

 

[Hogpatrol]

Did the brass look like that before firing? If not, I would find a local gunsmiths who can take a look at it with a quality borescope, e.g. a Hawkeye.

 

[Shootist43]

My gunsmith's shop is about 100 miles from where I live. Fortunately it is on the way to my cabin. I've already spoken with him and he is going to be taking a look at it this coming Saturday. He said that he has a Hawkeye borescope. After a short conversation he indicated that a polishing reamer might take care of the issue but that would be decided after the look-see. The more I think about it, the more plausible Ridgewalker's thought / idea becomes. IMHO there is no possible way for this to happen during normal machining / manufacturing operations. One thing for sure, I will be looking closely at a fired case before I accept the rifle back from my gunsmith. Tarbe, I should have done a profile of the neck before resizing the brass shame on me. I recently cleaned the bore thoroughly including complete copper removal using BoreTech CU +2 and don't want to foul it before the gunsmith does his thing.

 

[Ridgewalker]

I’m looking forward to what your gunsmith finds. Strange problem.

 

[tarbe]

I’m looking forward to what your gunsmith finds. Strange problem.

Me too!

 

[Opposite Pole]

Me too!

Dido

 

[GA Hunter]

The picture is not crystal clear but it resembles a case that has been partially neck sized. If that is the case then it would not be a rifle problem. It would be something to do with the reloading process. The die, shell holder, or maybe the way it was fed into the die. ‍

 

[Von S.]

I sent a pm two days ago...did you get it?

 

[fourfive8]

The picture is not crystal clear but it resembles a case that has been partially neck sized. If that is the case then it would not be a rifle problem. It would be something to do with the reloading process. The die, shell holder, or maybe the way it was fed into the die. ‍

That's exactly what it looks like. The sizing die is adjusted about half a neck length too far out. But won't know for certain until a look into the chamber.

If the chamber looks OK, then check the sizing die adjustment.

Until someone with a bore scope can look in there you can get a pretty good view into the chamber by putting the rifle in a cradle, shining a strong light down the muzzle and holding a skinny mirror near the breach to look into the chamber. Surprising how well it works for clear view of 3-4 inches into the chamber and at the throat area, etc.

 

[Pheroze]

Ok this may be daft, but what trim length are those cases? It looks to me like it was fire formed in a part narrower than the chamber?

 

[Inline6]

If that's what the cases looked like after firing you will need a new barrel.

I'm not going to sugar coat it, the neck is F'ed and cutting it out is probably not an option.

If you have a good gunsmith it is possible not probable that you can set it back. I would not bet money.

THAT IS MY HUMBLE OPINION

 

[Shootist43]

Von S., I did get your PM. I thought I canvas the membership to see if anyone else had ever seen this issue. Like you stated, this profile could not have been cut with a tool of any type. Ridgewalker offered what I think is the most viable probability. That is that there is a piece of old brass stuck in the neck, most likely broken off a work-hardened case sometime in the past. I'm hoping that it can be removed with a polishing reamer. The gunsmith that I use actually has 6 or 7 guys that have been in the trade 35 to 40 years working for him. I'll be taking the rifle to them on Saturday for their evaluation. After talking to the owner of the shop and explaining things, he didn't think it was going to be too big a deal. I'm keeping my fingers crossed that he is correct.

 

[Inline6]

I have had a rolled chip mess up more than one chamber.

Hope it is an easy fix.

I just worried if it was a broken neck you would never have been able to chamber a round.

 

[sestoppelman]

Something is amiss with the chamber itself I suspect, a ring of brass stuck is wishful thinking.

 

[nztimb]

Hoping there is a simple remedy for this as it does show there is something in the chamber that is impacting on the case neck

 

[Hogpatrol]

The best one can hope for is a carbon ring. Unlikely but one never knows.

 

[Shootist43]

Guys, thanks for all of your thoughts. Yea, I totally agree that there is something wrong with the chamber in the area of the cases neck like Von Gruff said. Since there is no way this could be done by a "cutting" tool, it has to be something to do with the rifle being fired. This is the first time I've ever had the need to use a good borescope, (read Hawkeye) if there is ever a second, it will probably be added to my "wish list."