Reloading for a semi

Smokinyotes

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When I first started loading for my semi 223 my loads shot great. Now that the new brass has all been fired, I was always under the impression that you need to full length resize for a semi so that is what I did. Now about a 1/3 of the rounds I’m getting light primer strikes and ftf. I never used a comparator when I resized these but after checking I have pushed the shoulder back about -003 too much.

New brass is 1.453”to the shoulder. My fired brass is 1.459”. The ones I pushed the shoulder back too far on are 1.450”.

Just wondering how far you guys push the shoulder back for reliable feeding in a semi?
 
do worry about the math
you set your die up and take a hand full of cases and keep turning the die down on a fired case when the bolt closes on the case you are done
if you need the specs then you could measure the case
 
When I first started loading for my semi 223 my loads shot great. Now that the new brass has all been fired, I was always under the impression that you need to full length resize for a semi so that is what I did. Now about a 1/3 of the rounds I’m getting light primer strikes and ftf. I never used a comparator when I resized these but after checking I have pushed the shoulder back about -003 too much.

New brass is 1.453”to the shoulder. My fired brass is 1.459”. The ones I pushed the shoulder back too far on are 1.450”.

Just wondering how far you guys push the shoulder back for reliable feeding in a semi?
You are correct, you do need to full length resize for a semi (or a bolt IMO) but your numbers may be excessive.

I have a Sheridan case gauge with cut away which has min / max recesses on the bottom, makes stuff like this easy. Keep lowering the die until it is in that range and you are good to go.
 
Set the die so the cases are sized to suit the rifle. The shell holder doesn't necessarily need to bump the die.
This ^^^^^ is accurate.

My precision bolt guns get 0.002" bump but you are trying to find the minimum that will feed reliably in a semi so it may be more than 0.002".
 
Any chance its simply a problem with the firing pin and bolt carrier? Maybe the firing pin isn't protruding like it use to owing to some dirt or debris?
 
Keeping track of brass for each rifle gets hard when you have 10, 20, 30 etc. guns shooting the same cartridge. Considering how much loading I have done with just a small base die screwed all the way down I am not sure it's the process at fault here.
 
This is on a Raven. Firing pin looks good. When I was pushing the shoulder back too far I had the die screwed down tight against the shell holder. When I mic the diameter of the case after resizing the diameter at the shoulder is the same as new brass, I’m thinking if I back the die off so my resized brass is only a couple thou longer than new brass at the shoulder this should probably work. I would be pushing the shoulder back .004 from the fired length of 1.459”
 
.002" shoulder bump should be good. Unless you want your gun to function in an extremely dirty situation. Do up a sample batch to check performance and loading/cycling. I'm just regurgitating what I have learned from ultimate reloader and others. Do the primers look deep seated?
 
I tend to agree with B #10 post and think your on the right track. Although I think .004" is still a little loose, but you will find out in the first couple rounds. I still recommend being tighter than loose for accuracy reasons and starting tight then bumping more if needed. If it cures the primer light strikes let us know. I'm curious. Cheers
 
Just a thought here but when you said your primers are seated flush it has me wondering if they aren’t seated deep enough and firing pin is pushing them forward without setting them off. I always seat mine just below flush. You can feel them with your finger.
 
This is on a Raven. Firing pin looks good. When I was pushing the shoulder back too far I had the die screwed down tight against the shell holder. When I mic the diameter of the case after resizing the diameter at the shoulder is the same as new brass, I’m thinking if I back the die off so my resized brass is only a couple thou longer than new brass at the shoulder this should probably work. I would be pushing the shoulder back .004 from the fired length of 1.459”
Hmmm, I know this is on a 223 Raven (which I am much less familiar with) but the 9mm Raven is infamous for breaking firing pins (I have lost count of the amount of people I have seen with that issue).

I had a similar issue on a Kriss Vector once and it was hard to pinpoint but it was firing pin related. From memory the pin broke but one part was still bumping the other part but it was marginally shorter due to the break which was causing light strikes. Food for thought.
 
To eliminate the gun being the issue it might be worth putting a few rounds of factory down the pipe.

If it runs fine on that then it is your reloads, if not the it is the gun.
 
I’m all to familiar with the Raven 9 breaking firing pins. I’m currently waiting for 1 now. My 223 worked without a hiccup with factory Hornady ammo and my Handloads using new Lapua brass. At first I tried the Hornady brass reloaded and had some light strikes and ftf. At first I thought maybe the Hornady brass had deeper primer pockets causing the issue but then it is doing the same thing with the resized Lapua brass. When I never had a issue when the brass was new lt made me wonder if it was a head space issue.
 
New brass is 1.453”to the shoulder. My fired brass is 1.459”. The ones I pushed the shoulder back too far on are 1.450”.

Just wondering how far you guys push the shoulder back for reliable feeding in a semi?
.001 - .002" is enough.

You are pushing the shoulder back by .009" which is way too much. Do this a few times and you will cause case head separations.

SAAMI headspace range is .004"
 
I realize I pushed the shoulder back too far that’s why I asked how far to push it back to reliably feed in a semi.
I went and took the firing pin out and inspected it again, other than probably being too wet with oil everything looks fine.
 
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