Problem with chambering

Twycross · March 13, 2012, 04:32 PM

I reload 7mm WSM, and the last batch had an issue I cannot figure out. All the rounds I did that day were stiff to chamber, difficult to extract, and several showed signs of overpressure.

I've never had this issue with factory ammunition, or with anything else I've reloaded. I've checked the unfired loads from this batch, and they are dimensionally identical to the round I reloaded just now (which chambers fine), and well within specs. Anybody know what might have caused this?

Wyoredman · March 13, 2012, 04:39 PM

Were the reloads you were using the once fired Winchester Nickle brass? Had this problem in my .270 WSM. The Winchester nickle brass was not resizing in my dies. I had to adjust them down nearly another 1/2 turn to get them to size the nickle.

PA-Joe · March 13, 2012, 04:56 PM

What were the signs of over pressure? When was the last time you calibrated your scale? What scale are you using and did you spot check every 5th round? Also when was the last time you gave your chamber a good cleaning?Type of dies and cases might also help.

Twycross · March 13, 2012, 05:07 PM

Quote:

Were the reloads you were using the once fired Winchester Nickle brass?

Yes, that is the brass I was using. But it seems to be sized correctly, and I haven't had this issue when using the same once-fired type in other batches.

Quote:

When was the last time you calibrated your scale? What scale are you using and did you spot check every 5th round? Also when was the last time you gave your chamber a good cleaning? Type of dies and cases might also help.

I use RCBS dies, and I check every round (I load in small quantity). The chamber is clean, but even if not, it shouldn't matter. I can chamber a round from the batch in question, and then a factory round or a round I just loaded, and feel the difference.

As to the signs of overpressure, two primers were completely ejected from the primer pocket.

Wyoredman · March 13, 2012, 05:18 PM

It is the brass. Adjust your dies down and, resize again, then try the re-resized brass in the gun again. I promise, it will work.

The nickel brass from Winchester (for my WSM, anyway) does NOT size the same as regular brass! My die settings for regular brass and Winchester nickel are differant.

This will not help your overpressure problem, just your initial chambering problem. If the primers came out, is your bolt face burnt?

mrawesome22 · March 13, 2012, 05:37 PM

Screw die in farther. Use less powder.

mehavey · March 13, 2012, 06:23 PM

nickel-plated cases stiffen up quickly -- both in handguns and in rifles. In handguns they begin to spit at the neck, in high-pressure rifles they become more resistant to sizing. It's a well-documented metallurgical "feature,"

Brass is a handloader's friend.
Nickel plating is not

math teacher · March 13, 2012, 06:45 PM

Can you slip a bullet into a fired nickel case? I have had new nickel cases with necks that are too thick making them difficult or impossible to chamber. That will definately cause excess pressure as the neck has no room to expand. The entire case is probably thicker than unplated brass, but the neck is the critical part. If you can't easily slip a bullet into a fired case neck, you need to ream the necks.

xtratoy · March 13, 2012, 07:34 PM

Adjusting the dies won't fix the primer pocket situation.

mehavey · March 14, 2012, 07:54 AM

Quote:

Originally Posted by OP

As to the signs of overpressure, two primers were completely ejected from the primer pocket.

I just went back to read that. You are waaaaaay overpressure ... 80,000psi range.

It may be any number of things, from internal case volume differences to case neck interference
in the throat, to bullet seating depth, ...but back off at least 1½ to 2 full grains with that
bullet/case/powder combination.

Verify that the cases are trimmed to min-length spec (<2.1" ?)
...and see if you can scounge up a chronograph

PA-Joe · March 14, 2012, 11:57 AM

You didn't say what your load was.

That may help.

tango1niner · March 14, 2012, 12:08 PM

This does not address the over pressure issue as that has been mentioned already but... read someones post about screwing the sizer die down more. The shell holder should be set to contact the sizing die when sizing.

Twycross · March 14, 2012, 01:35 PM

The load was 68 gr Magpro w/ 160 gr Accubond. That's straight from the Nosler manual, and it's not a maximum charge.

What I don't get is that everything I did on that day exhibited the same chambering problems, and I cannot recreate it. I'm holding a bad round, a round I just reloaded using the same brass/bullet, and a factory round, and only the bad one is tight to chamber. I've gone over them with a micrometer, and all three are dimensionally identical to within 0.002".

Quote:

Can you slip a bullet into a fired nickel case?

Yes, that can be done easily.

Quote:

Verify that the cases are trimmed to min-length spec

They are in spec, at 2.093".

Quote:

The shell holder should be set to contact the sizing die when sizing.

I'm doing that.

PA-Joe · March 15, 2012, 05:20 AM

There may be some dirt under your shellholder. The WSMs tend to have very tight chambers. I know that if you use a different brand of shellholder than your die company they are not machined to the same standards and people have had to sand off .001 from the top of the shellholder to kick the shoulders back enought.

March 13, 2012, 04:32 PM	#1
Twycross Senior Member Join Date: January 26, 2005 Location: Montana Posts: 1,187	Problem with chambering I reload 7mm WSM, and the last batch had an issue I cannot figure out. All the rounds I did that day were stiff to chamber, difficult to extract, and several showed signs of overpressure. I've never had this issue with factory ammunition, or with anything else I've reloaded. I've checked the unfired loads from this batch, and they are dimensionally identical to the round I reloaded just now (which chambers fine), and well within specs. Anybody know what might have caused this? __________________ The test of character is not 'hanging in' when you expect light at the end of the tunnel, but performance of duty, and persistence of example when you know no light is coming. - Vice Admiral James Stockdale, USN (ret.)

March 13, 2012, 04:39 PM	#2
Wyoredman Senior Member Join Date: September 6, 2011 Location: Wyoming Posts: 1,350	Were the reloads you were using the once fired Winchester Nickle brass? Had this problem in my .270 WSM. The Winchester nickle brass was not resizing in my dies. I had to adjust them down nearly another 1/2 turn to get them to size the nickle. __________________ Go Pokes! Go Rams!

March 13, 2012, 05:18 PM	#5
Wyoredman Senior Member Join Date: September 6, 2011 Location: Wyoming Posts: 1,350	It is the brass. Adjust your dies down and, resize again, then try the re-resized brass in the gun again. I promise, it will work. The nickel brass from Winchester (for my WSM, anyway) does NOT size the same as regular brass! My die settings for regular brass and Winchester nickel are differant. This will not help your overpressure problem, just your initial chambering problem. If the primers came out, is your bolt face burnt? __________________ Go Pokes! Go Rams!

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March 13, 2012, 04:56 PM	#3
PA-Joe Senior Member Join Date: June 9, 2010 Location: NEPA Posts: 909	What were the signs of over pressure? When was the last time you calibrated your scale? What scale are you using and did you spot check every 5th round? Also when was the last time you gave your chamber a good cleaning?Type of dies and cases might also help.

March 13, 2012, 05:37 PM	#6
mrawesome22 Senior Member Join Date: November 9, 2005 Location: Ohio, Appalachia's foothills. Posts: 3,779	Screw die in farther. Use less powder.

March 13, 2012, 06:23 PM	#7
mehavey Senior Member Join Date: June 17, 2010 Location: Virginia Posts: 6,883	nickel-plated cases stiffen up quickly -- both in handguns and in rifles. In handguns they begin to spit at the neck, in high-pressure rifles they become more resistant to sizing. It's a well-documented metallurgical "feature," Brass is a handloader's friend. Nickel plating is not

March 13, 2012, 06:45 PM	#8
math teacher Senior Member Join Date: February 5, 2012 Location: Southwest WA Coast Posts: 558	Can you slip a bullet into a fired nickel case? I have had new nickel cases with necks that are too thick making them difficult or impossible to chamber. That will definately cause excess pressure as the neck has no room to expand. The entire case is probably thicker than unplated brass, but the neck is the critical part. If you can't easily slip a bullet into a fired case neck, you need to ream the necks.

March 13, 2012, 07:34 PM	#9
xtratoy Junior Member Join Date: March 12, 2007 Location: Vancouver WA Posts: 5	Adjusting the dies won't fix the primer pocket situation.

March 14, 2012, 11:57 AM	#11
PA-Joe Senior Member Join Date: June 9, 2010 Location: NEPA Posts: 909	You didn't say what your load was. That may help.

March 14, 2012, 12:08 PM	#12
tango1niner Senior Member Join Date: March 5, 2009 Location: NY Posts: 317	This does not address the over pressure issue as that has been mentioned already but... read someones post about screwing the sizer die down more. The shell holder should be set to contact the sizing die when sizing.

March 15, 2012, 05:20 AM	#14
PA-Joe Senior Member Join Date: June 9, 2010 Location: NEPA Posts: 909	There may be some dirt under your shellholder. The WSMs tend to have very tight chambers. I know that if you use a different brand of shellholder than your die company they are not machined to the same standards and people have had to sand off .001 from the top of the shellholder to kick the shoulders back enought.