Thread: Can The Lee FL Die Do A Shoulder Bump?

@Rn-85 if you send me a pm we can do a video call and I can help you out with your reloading if you want.

Your Lee F/L die will be just fine for what you're wanting to do. Which is full length resize to the shoulder being 0.002" shorter than your chamber to avoid chambering issues.

Originally Posted by Rn-85

I think I'll go to that method after all I really like using my lee loader.

Is the correct process to trim before fl resize?

Sorry for the newbie questions.

Its a good question and Dicko is correct. Folk do seem to confuse it tho. Just remember the case is length stretched in two actions. First is when you fire the round and the case expands to the form of the chamber which is always larger and longer to allow the round to be chambered. Second is when the case is sized forcing it back to original dimensions. Both instances cause the case to lengthen. The brass walls thin a tad under firing pressure and sizing. The brass has to go somewhere and it flows into extra length. You can test this by trimming to length say 50 cases before FL sizing. Then gauge again. A few will require retrimming. It won't be consistent because cases still vary in wall thickness in the body. And it will be a very marginal amount. Nevertheless it is enough to affect accuracy to some degree. In very tight chambers it may cause difficulty closing the bolt. In a tolerant chamber it probably makes little difference for hunting.

Originally Posted by Rn-85

So do most of you shoulder bump or fl resize? And can it be done with a standard lee die?

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FL sizing and bumping the shoulder is the same thing, bumping the shoulder the method of trying to work the brass as little as possible, rather than sizing it back to Sammi specs which would be unnecessary if using the brass in only one rifle.

What brass are you using?
How many firings?
What cartridge?
Depending on all the above would help diagnose the issue.

Personally if you have slowly adjusted the die so that you have minimal bump and they all chamber, and the brass has only be used a few times, I'd just load them up and see what happens. Slight variations in brass wil make next to no difference for most shooters anyway.
So long as they reliably chamber that's all the really matters.

look up partial length resizing...thats what you are doing now.....using full length die but not pushing things right back..just enough to chamber properly. as to if shoulder has moved??? in theory,just a little bit,same with squeazing side walls... when doing this on the tiny 7.62x39mm we can see a double shoulder EG can see the die doesnt go all the way down the neck as it would if die was wound right down.

I've only had tough chambering when I was neck sizing only with the lee loader.

308
Starline brass.

I'm doing it in batches so I've got 20 cases where I've reloaded them about 3-5 times so need to resize and reset them. Those ones I was trying to bump.

I've started a new batch of 20 which are new unfired brass.

I'm not running a super hot load only 42 grain of 2206h behind a 165sst.

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If I were you I'd leave the 3-5 fired cases for now, they probably need annealing so may be giving you measurement issues.

Shoot the 20 new pieces of brass and measure them all after on firing with the Hornady tool.
If they are all measuring the same then set the FL dies up so that it's just setting them back .002" off the fired size.
This should give you the most accurate measurements using what you have at hand.

The idea behind bumping the shoulder is that you do that after ever firing. The older method was to neck size only for 2-4 firings and then FL size before they start get difficult to chamber. But you really want to be avoiding them ever being difficult to chamber, so FL sizing them the bare minimum is the beat way to ensure consistency while not over working the brass.

The 3-5 fired cases probably need trimming, which may be contributing to your difficulty in chambering.
You should trim the cases after resizing.

Originally Posted by Rn-85

I've only had tough chambering when I was neck sizing only with the lee loader.

308
Starline brass.

I'm doing it in batches so I've got 20 cases where I've reloaded them about 3-5 times so need to resize and reset them. Those ones I was trying to bump.

I've started a new batch of 20 which are new unfired brass.

I'm not running a super hot load only 42 grain of 2206h behind a 165sst.

Sent from my SM-G780G using Tapatalk

aha got you now...neck sizing using lee whackamole set??...... so do the full length resize back to spec...it will grow back on next fireing and then will be whackamolable for the next 5-6 times again LOL. so in effect youve only done the large growth once....not a big deal.

Originally Posted by Beetroot

If I were you I'd leave the 3-5 fired cases for now, they probably need annealing so may be giving you measurement issues.

Shoot the 20 new pieces of brass and measure them all after on firing with the Hornady tool.
If they are all measuring the same then set the FL dies up so that it's just setting them back .002" off the fired size.
This should give you the most accurate measurements using what you have at hand.

The idea behind bumping the shoulder is that you do that after ever firing. The older method was to neck size only for 2-4 firings and then FL size before they start get difficult to chamber. But you really want to be avoiding them ever being difficult to chamber, so FL sizing them the bare minimum is the beat way to ensure consistency while not over working the brass.

The 3-5 fired cases probably need trimming, which may be contributing to your difficulty in chambering.
You should trim the cases after resizing.

You can also achieve great consistency by annealing every time and you avoid being a gorilla when sizing.