Incomplete Full Length Resize Causing Chambering Difficulty

harbl_the_cat

harbl_the_cat

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I was loading .308 range brass the past few weeks and at the range I discovered that alot of the casings were VERY hard to chamber (in 2 instances, impossible) in my Marlin XL7. I could almost completely chamber the round, but locking the bolt was the very difficult part.

Some research and investigation and I discovered that my Lee Full Length Sizing die is the likely culprit - specifically, that I did not screw it in all the way (Lee recommends screwing it in until the die contacts the case plate, with the ram raised, than screwing it in 1/4 to 1/3 turn more).

I think I also FL resized several hundred .223 cases as well, where my die wasn't screwed in sufficiently.

Thing is, with the .223's - they're only being fired from my Nork AR's and SU-16. I haven't had any problems with my existing test fires, but I'd like some reassurance from anyone if they think I should have any problems with this brass (and if it merits another FL resize?).

Does anyone know if the SU-16 and Nork AR chambers have a pretty forgiving tolerance?
 
weldboss said:
Why full length size at all in a bolt action? Just neck size from now on you won't have this issue again and it's easier on your brass in the long run.
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OP reported that this was range brass. Not originally fired in his rifle. FL sizing just about mandatory.

Harbl - your .223s are likely a bit more generous in their chambers, which is why the incompletely FL sized cases are chambering. Might be OK. In some semis, you do not want a round to hang up just before lockup.
 
if you can't close the bolt, the problem is likely the need for bumping, not likely because the case is too "fat". The chambers these were fired from probably had sloppy headspace and they are too long for your chamber. Brass that is too wide sticks in a chamber and is sometimes brutal to try and remove. I think the problem is shoulder length.

To get your brass to work properly in a semi, you should probably FL size as they dont feed well if too tight.
 
I read over and over why not JUST neck size. So many people do not understand how to properly size brass for optimal performance and life.

Some of the best reads are the Bench Rest primer and Tony Boyers book. You do not need to shoot BR to learn valuable reloading.

The issue may not even be that the shoulder is not moved back enough. If you are getting the dreaded click when the bolt cams on opening the web area is not getting sized enough. This will cause stiff bolt closing as well.

Thump err has hit the nail on the head. There is no substitute for using measurements to see what is exactly happening when resizing brass
 
The way they describe it in the die instructions is the monkey way of setting up a die. It guarantees that you will be over-sizing the brass, which will lead to premature head separation.

thump_rrr said:
I set up all of my full length dies using a case gauge.
This allows you to see if you are pushing the shoulder back enough or too much.
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^^This is the right ways to do it.

Read this:
http://bulletin.accurateshooter.com/2012/10/tech-tip-how-to-set-your-dies-for-correct-shoulder-bump/
 
harbl_the_cat said:
I was loading .308 range brass the past few weeks and at the range I discovered that alot of the casings were VERY hard to chamber (in 2 instances, impossible) in my Marlin XL7. I could almost completely chamber the round, but locking the bolt was the very difficult part.

Some research and investigation and I discovered that my Lee Full Length Sizing die is the likely culprit - specifically, that I did not screw it in all the way (Lee recommends screwing it in until the die contacts the case plate, with the ram raised, than screwing it in 1/4 to 1/3 turn more).

I think I also FL resized several hundred .223 cases as well, where my die wasn't screwed in sufficiently.

Thing is, with the .223's - they're only being fired from my Nork AR's and SU-16. I haven't had any problems with my existing test fires, but I'd like some reassurance from anyone if they think I should have any problems with this brass (and if it merits another FL resize?).

Does anyone know if the SU-16 and Nork AR chambers have a pretty forgiving tolerance?
Click to expand...

Did you trim the cases to make sure they weren't over the max length? If it was range brass there's a pretty good chance that at least some of them were too long which can cause chambering problems.
 
My Israeli Mauser will not accept brass that has been fired in my M305 despite being full length resized. I need to keep them separate. As for neck sizing, not recommended for semi-auto and from my own experience it will jam.
 
Colin said:
My Israeli Mauser will not accept brass that has been fired in my M305 despite being full length resized. I need to keep them separate. As for neck sizing, not recommended for semi-auto and from my own experience it will jam.
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RCBS and Redding both make small base dies that should solve your problem.
 
I had a problem with the bolt not completely closing on my .223 semi even after full length resizing.Was talking to a rather experienced clerk/reloader about ordering a small base set.He said he had a trick i should try first before spending my money.He said to grind down the shell holder so it exposes more of the case then adjust the sizer down.i tried it and voila !
 
puterbrother said:
I had a problem with the bolt not completely closing on my .223 semi even after full length resizing.Was talking to a rather experienced clerk/reloader about ordering a small base set.He said he had a trick i should try first before spending my money.He said to grind down the shell holder so it exposes more of the case then adjust the sizer down.i tried it and voila !
Click to expand...

Be careful doing that. You might be creating an excess headspace situation.
Before going that route, it might be an idea to determine why the round won't chamber, and then addressing the specific cause.

As an example, my Mk. II** Ross target rifle has the expected tight chamber. It will not accept a full length sized case fired in any Lee Enfield. Getting the casing further into the sizing die would make no difference; the issue was the diameter of the case in front of the rim, not the length of the case to the shoulder. I simply made a die to reduce the diameter of the last half inch of the case to original factory dimensions, and the problem was solved.
 
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