Full Length resizing question

BLS700 · August 31, 2009, 11:32 AM

I had an issue w/ primers not firing before that I brought to the forum. I don't know that this has anything to do with it but I noticed that the cases I had fired in my TC Prohunter had the shoulders moved forward noticeably from the cases I had full length resized and were still unfired? So for the next batch instead of tightening the die a quarter turn farther down I backed it a quarter turn up. I know I've seen posts where guys don't go the whole way down on their FL resizing but I thought I'd check with some more experienced loaders to make sure this isn't going to pose any safety issues provided the cases don't need to be shoved into the chamber. Again I doubt this had anything to do with the primers not firing but if any of you had seen or can see a connection please feel free to let me know becaue it's driving me NUTS!!

LHB1 · August 31, 2009, 03:01 PM

Forget the quarter turn up/down business. Measure Base to Shoulder and Base to Neck lengths of new unfired brass, brass fired in your chamber, and your fired brass after resizing. Then adjust full length sizing die until the shoulder is just barely (.002"?) moved back enough to let the fired case chamber easily. Do NOT push shoulder back further than new factory brass. Then lock your die and it is properly adjusted for your gun.

dmazur · August 31, 2009, 10:57 PM

A Wilson-type cartridge headspace gauge is recommended for setting up resizing dies. From the instructions Dillon includes with their dies -

Quote:

We strongly suggest that a headspace case gage be used to correctly adjust the size die.

There are at least two different ways to use this gauge:

1. Adjust resizing die until brass shows "between" lower and upper step on the gauge. Verify that this length will chamber easily in all rifles you intend to fire it in. This is a method to set headspace to SAAMI spec.

2. Drop a fired case in the gauge, measure depth from gauge bottom with calipers, then adjust resizing die until that case measures 0.002" shorter. This is correct cartridge headspace for that rifle.

There are some things to note when adjusting headspace. Typically the difference between SAAMI minimum and maximum is only 0.006" or so. This isn't much, and is very hard to set using "1/4 turn on lock ring" methods.

While manufacturers try to set die dimensions so that the user can't easily adjust a die for excessive headspace (because it is dangerous), that doesn't mean it can't be done. One symptom of excessive headspace is that the firing pin can't reach the primer...

If you get a gauge, you can set the resizing die correctly and eliminate that as a possible source of ignition problems.

Jim243 · September 1, 2009, 12:26 AM

It will not help your problem if using new brass but might if using once fired brass from THAT gun. It sounds like your brass is streaching becasue of head space problems with the gun. How is the recoil? Extra heavy or normal?

I would try to fix the problem not the symtoms. If I get a headach every time it hit my head on the wall, taking asprin will not cure the problem.

Good luck
Jim

BLS700 · September 1, 2009, 09:33 AM

Agreed. I'm attempting to fix the problem. I'm going to get a headspace gauge before I do any more sizing. This is a new gun and the first time I've had issues of this sort so I'm still learning really. To be honest I probably wouldn't have noticed the headspace issue had I not been inspecting the cases so much after the primers didn't fire.

August 31, 2009, 11:32 AM	#1
BLS700 Senior Member Join Date: June 18, 2008 Location: Pennsylvania Posts: 229	Full Length resizing question I had an issue w/ primers not firing before that I brought to the forum. I don't know that this has anything to do with it but I noticed that the cases I had fired in my TC Prohunter had the shoulders moved forward noticeably from the cases I had full length resized and were still unfired? So for the next batch instead of tightening the die a quarter turn farther down I backed it a quarter turn up. I know I've seen posts where guys don't go the whole way down on their FL resizing but I thought I'd check with some more experienced loaders to make sure this isn't going to pose any safety issues provided the cases don't need to be shoved into the chamber. Again I doubt this had anything to do with the primers not firing but if any of you had seen or can see a connection please feel free to let me know becaue it's driving me NUTS!!

August 31, 2009, 03:01 PM	#2
LHB1 Senior Member Join Date: March 25, 2005 Location: Houston, TX Posts: 1,545	Forget the quarter turn up/down business. Measure Base to Shoulder and Base to Neck lengths of new unfired brass, brass fired in your chamber, and your fired brass after resizing. Then adjust full length sizing die until the shoulder is just barely (.002"?) moved back enough to let the fired case chamber easily. Do NOT push shoulder back further than new factory brass. Then lock your die and it is properly adjusted for your gun. __________________ Good shooting and be safe. LB

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September 1, 2009, 12:26 AM	#4
Jim243 Senior Member Join Date: January 5, 2009 Location: Just off Route 66 Posts: 5,067	It will not help your problem if using new brass but might if using once fired brass from THAT gun. It sounds like your brass is streaching becasue of head space problems with the gun. How is the recoil? Extra heavy or normal? I would try to fix the problem not the symtoms. If I get a headach every time it hit my head on the wall, taking asprin will not cure the problem. Good luck Jim

September 1, 2009, 09:33 AM	#5
BLS700 Senior Member Join Date: June 18, 2008 Location: Pennsylvania Posts: 229	Agreed. I'm attempting to fix the problem. I'm going to get a headspace gauge before I do any more sizing. This is a new gun and the first time I've had issues of this sort so I'm still learning really. To be honest I probably wouldn't have noticed the headspace issue had I not been inspecting the cases so much after the primers didn't fire.