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Chambering problems

Rico

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Joined
Mar 8, 2019
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43
I’m looking for some advice. I am working on my first ever handload. Its for a 338 win mag. I loaded up my first batch of test rounds and they chambered with no problems at home, a couple weeks ago. I went to the range this morning and none of them will chamber, they are all too tight. Factory rounds will chamber with no problem. I worked up some dummy rounds, increasing the seating depth by a large margin and bumping the shoulder all the way out to match the factory rounds - still won’t chamber. The only difference I could find between mine and the factory rounds was the diameter at the base just above the belt is running about 5 thousandths. Could that be it? If so, what can I do about it? I assume the Florida heat and humidity is the reason for the difference from when I loaded them until today, but surely a full length sizing die works in the summertime too, right?
 
That seems pretty extreme. Just throwing out a couple of theories-- OAL between your reloads and the factory loads match? What about case neck length between your reloads and the factory loads? Could there be a thin film of oil on the reloads or in the chamber?
 
That seems pretty extreme. Just throwing out a couple of theories-- OAL between your reloads and the factory loads match? What about case neck length between your reloads and the factory loads? Could there be a thin film of oil on the reloads or in the chamber?
He indicated that newly loaded handloads chambered with no problems. I would never do that except outside or at the range.
 
I’m looking for some advice. I am working on my first ever handload. Its for a 338 win mag. I loaded up my first batch of test rounds and they chambered with no problems at home, a couple weeks ago. I went to the range this morning and none of them will chamber, they are all too tight. Factory rounds will chamber with no problem. I worked up some dummy rounds, increasing the seating depth by a large margin and bumping the shoulder all the way out to match the factory rounds - still won’t chamber. The only difference I could find between mine and the factory rounds was the diameter at the base just above the belt is running about 5 thousandths. Could that be it? If so, what can I do about it? I assume the Florida heat and humidity is the reason for the difference from when I loaded them until today, but surely a full length sizing die works in the summertime too, right?
Sounds like you may need a small base die. Your brass may be "springing" back over the couple of weeks time. I've not seen it all so I can't say if there is such a thing as a small base die for a belted magnum.
 
Love the 338 Win
Simple just adjust your sizer die down 1/4 turn until brass loads great into your rifle . Doing this sets the shoulder back just a tad for easy loading .
 
Use a larry willis die to size ahead of the belt. If you full length and bump with a fl die, set it to correctly bump your shoulder and leave it there. Use the fl sizer after the willis die.
Measure the shoulder on 2x fired brass (2x minimum) and set your bump to be .002 under that; your brass will have minimal stretch
 
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Cover your handloaded rounds in sharpie pen ink or carbon black and run them in the chamber them again. You will see instantly where the choke point is.

Reamers wear out. A chamber cut with an end of life reamer may be tight, even if it takes the gages ok.

Another answer could be to get one of these. I use L.E. Wilson gages extensively. If your finished handload drops in the gage and is flush at the base, it is at SAAMI Spec.
You can adjust them to fit your once fired casings if you want. I leave mine at SAAMI Spec. Plus, you don't have the safety questions of chambering a round at the loading bench. This is a big plus if you are checking "bet your life" 5.56 or 7.62 handloads in your favorite semi-auto personal defense weapon


+1 on the full length or small base die comments. I am betting your observation about the bases of the handloads being fatter is very relevant to this.

I stopped using neck only sizers for hunting loads a while ago. Consistent, easy feeding is a higher priority than bench rest accuracy in a hunting round.
 
Use a larry willis die to size ahead of the belt. If you full length and bump with a fl die, set it to correctly bump your shoulder and leave it there. Use the fl sizer after the willis die.
Measure the shoulder on 2x fired brass (2x minimum) and set your bump to be .002 under that; your brass will have minimal stretch

^this was my first thought.

Not sure I fully understand the story about how it fed and then it didn’t and what happened between but that doesn’t seem like something that should happen based on sizing. Only other thing i can think of is it was a heavily compressed charge and the bullets pushed out to a longer coal to where they are jamming hard.
 
That seems pretty extreme. Just throwing out a couple of theories-- OAL between your reloads and the factory loads match? What about case neck length between your reloads and the factory loads? Could there be a thin film of oil on the reloads or in the chamber?
COAL is about 20 thousandths longer. Factory loads are 200 grain federal premium trophy bonded tip. I’m using 205 hammers for the reloads.
I also found that the diameter at the neck seems to be running slightly bigger than the factory loads by a few thousands also.
 
^this was my first thought.

Not sure I fully understand the story about how it fed and then it didn’t and what happened between but that doesn’t seem like something that should happen based on sizing. Only other thing i can think of is it was a heavily compressed charge and the bullets pushed out to a longer coal to where they are jamming hard.
The load isn’t compressed. When you shake it, you can hear the powder moving around. This got me thinking though. The rounds I chambered a couple weeks ago at the bench were dummy rounds, sized and with bullets seated, but no powder. I wouldn’t have thought adding powder in a non-compressed load would have caused a difference in the final size. I was using them to find my seating depth. I found the jam point, then backed up 30 thousandths, then loaded up my test rounds at 30, 35, 40, 45, etc from jam. At the range, none of them would chamber. I came back home, loaded up a dummy round, and it wouldn’t chamber. Then I bumped its shoulder way back - no go. Then I re-seated the bullet way way deep, still no go. They are hanging up in the chamber way before the bullet could be jamming. Its got to be something with the case
 
Have you tried chambering a case right after sizing it? Do that and see what happens. If it chamber's fine then check the length from bolt face to lands, I use a cleaning rod. If it chambers hard or not at all, it's the seating depth and you'll see scratch marks around the bullet by the lands. You said your new to this and this is your first time. Yet your already working on bumping the shoulder rather than running the case all the way into the die to FL size it? Sounds to me like its a bit soon to start experimenting. Learn to make good ammo first.
 
The Willis die is a good thing to have regardless. I’d give that a try.

to get this straight, this is with brass that has never been fired?
 
Mark the casing with a sharpie like was suggested above.

I had a .243 die that would not set the shoulder back far enough to chamber. I’m guessing it was a compatibility issue with my shell holder.
 
Update: I reset the resizing die (a brand new Lyman full length resizing die) all the way down to contact the shell holder then backed it off about a quarter turn. An empty case sized this way chambers with no issue. Then I loaded up some live rounds, using the minimum charge and setting the bullet at the same depth as the factory rounds. These live rounds will not chamber. The cases must be expanding when loaded with powder, even though they aren’t compressed (I an still hear powder moving around when shaken).
 
Mark the casing with a sharpie like was suggested above.

I had a .243 die that would not set the shoulder back far enough to chamber. I’m guessing it was a compatibility issue with my shell holder.
Will definitely try marking the case next.

Thanks everyone for your help with this. Its super frustrating. I appreciate your input very much
 
Update: I reset the resizing die (a brand new Lyman full length resizing die) all the way down to contact the shell holder then backed it off about a quarter turn. An empty case sized this way chambers with no issue. Then I loaded up some live rounds, using the minimum charge and setting the bullet at the same depth as the factory rounds. These live rounds will not chamber. The cases must be expanding when loaded with powder, even though they aren’t compressed (I an still hear powder moving around when shaken).
Readjust your seating die. It might be putting pressure on the case, causing a slight bulge in the shoulder somewhere. If the bullet isn’t making contact with the lands, your seating die is messing you up.
 
Readjust your seating die. It might be putting pressure on the case, causing a slight bulge in the shoulder somewhere. If the bullet isn’t making contact with the lands, your seating die is messing you up.
Also does the die have a small vent (hole) near the top? It may be plugged. My 7 mag dies have a port and if it's plugged it will dent cases and some won't load. Been a long time since it happened. I always wipe lube off brass after sizing.
 
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