Shoulder bump?

[BoulderE89]

Saw a YouTube video of a guy claiming that bumping the shoulder back in bolt action rifles was wrong. Far as I can tell it’s a widely common practice and not bumping the shoulder is the rare exception. He also ran his bolt stiff when camming it as a result, which doesn’t seem like a good idea. Anyone have any reason as to if one should or should not do this. I’ve always been under the impression bumping .002 back was the standard.

 

[John Glidewell]

 

[spife7980]

Saw a YouTube video of a guy claiming that bumping the shoulder back in bolt action rifles was wrong. Far as I can tell it’s a widely common practice and not bumping the shoulder is the rare exception. He also ran his bolt stiff when camming it as a result, which doesn’t seem like a good idea. Anyone have any reason as to if one should or should not do this. I’ve always been under the impression bumping .002 back was the standard.

Was it this video?


If so... the reasons he gives to not full length size are the exact reasons that we do. The person who made this video are retarded. Follow the wheeler video above.




Listen to this video that the retard above made his in response to

 

[ZiaHunter]

Agree with Spife. I have shot competitively with Eric Cortina and have long discussion with him in the pits. He is an excellent shooter and knows his business. In my experience tight bolt close is going to result in a flier at extended ranges. When I encounter one it goes back into the box and may use it for a sighter but not for record. Years ago I played around with neck sizing but FL size everything now. The only time I neck size if I have to size the neck more than .005 and finish with a FL sizing.

 

[BoulderE89]

So we can still universally agree FL sizing with setting the shoulder back .002 is the standard for case prep? And yes it was that video. His attitude in the video is annoying as hell but I thought it was worth asking just to be sure I wasn’t missing something

 

[Supersubes]

I’ve seen that vid, and like spife said, dude is a tard! Yes you can bump the shoulders. If you don’t like .002, try .001. Just have some clearance.

 

[Mainer]

Anyone else have problems holding shoulder bump to a tight tolerance?

My headspace dim varies by .003 with an occasional outlier of .006 or so. I am guessing that much of it is caused by springback?

 

[spife7980]

Anyone else have problems holding shoulder bump to a tight tolerance?

My headspace dim varies by .003 with an occasional outlier of .006 or so. I am guessing that much of it is caused by springback?

Youre gonna have to give way more info than that, actual details, for any sort of real answer. Im inclined to place blame on your measurement techniques or shit brass at this point.

 

[Supersubes]

Anyone else have problems holding shoulder bump to a tight tolerance?

My headspace dim varies by .003 with an occasional outlier of .006 or so. I am guessing that much of it is caused by springback?

Not spring back. Press rigidity perhaps, press technique(hold at the bottom of the stroke).
Redding comp shell holders are great, try them.

 

[Milo 2.5]

Saw a YouTube video of a guy claiming that bumping the shoulder back in bolt action rifles was wrong. Far as I can tell it’s a widely common practice and not bumping the shoulder is the rare exception. He also ran his bolt stiff when camming it as a result, which doesn’t seem like a good idea. Anyone have any reason as to if one should or should not do this. I’ve always been under the impression bumping .002 back was the standard.

Tight in, tighter out, not like fucking.
You may get by with a neck size after first firing, after that bump. You can also do a little measuring and make your cases grow some in length after first firing, but you want them all the same.
Some respected guy on lRH claims he can bump brass up to 8 thou with his bolt, don't be him, you'll be buying a new action.

 

[Tokay444]

So we can still universally agree FL sizing with setting the shoulder back .002 is the standard for case prep? And yes it was that video. His attitude in the video is annoying as hell but I thought it was worth asking just to be sure I wasn’t missing something

Yes, BUT, only once you're sure your brass has grown to full chamber size. I don't normally bump the shoulder until after my second firing. So far this has resulted in me never having to trim my brass, because it doesn't grow. It's not being worked enough.

 

[Milo 2.5]

So far this has resulted in me never having to trim my brass, because it doesn't grow. It's not being worked enough.

And how many rifles is this on? Not the norm.

 

[BoulderE89]

Yes, BUT, only once you're sure your brass has grown to full chamber size. I don't normally bump the shoulder until after my second firing. So far this has resulted in me never having to trim my brass, because it doesn't grow. It's not being worked enough.

So after first firing you just back of the sizing die to not mess with the shoulder?

 

[Tokay444]

And how many rifles is this on? Not the norm.

Two barrels now on the same rifle.

 

[Dthomas3523]

I’ve heard a lot of people say they let their brass grow a few firings before bumping.

In about 20-25 barrels I’ve checked, I’ve never had the brass not grow enough that it doesn’t need the shoulder bumped.

Not saying it doesn’t happen, just haven’t seen it yet.

I also prefer my bolt to fall freely as shown in the wheeler video above.

 

[Trek]

Is .004 “too much” bump? New to reloading, but I have once fired Lapua 308, Amp annealed, Redding S FL die (no expander ball/nor pin), screws to the stop on a Forster Coax. I’ve been chasing “up” the die by unscrewing and using a lock ring to hold, but would like (wish) to have the die screwed down for consistency... would .004 overwork the brass, even if it was annealed every firing? (AIAX, factory barrel)... thanks for the input.

 

[Supersubes]

Is .004 “too much” bump? New to reloading, but I have once fired Lapua 308, Amp annealed, Redding S FL die (no expander ball/nor pin), screws to the stop on a Forster Coax. I’ve been chasing “up” the die by unscrewing and using a lock ring to hold, but would like (wish) to have the die screwed down for consistency... would .004 overwork the brass, even if it was annealed every firing? (AIAX, factory barrel)... thanks for the input.

Brass that has been oversized doesn’t fail in the area which you anneal, it fails in the web area. I think .004 is too much personally. No reason you shouldn’t be able to hold .001-.002.

 

[Dthomas3523]

People bump back .004+ all the time for gas guns. It won’t hurt, but won’t be ideal.

Most of my chambers fall in the .0025 or so area for the bolt to fall free.

 

[Ryridesmotox]

Is .004 “too much” bump? New to reloading, but I have once fired Lapua 308, Amp annealed, Redding S FL die (no expander ball/nor pin), screws to the stop on a Forster Coax. I’ve been chasing “up” the die by unscrewing and using a lock ring to hold, but would like (wish) to have the die screwed down for consistency... would .004 overwork the brass, even if it was annealed every firing? (AIAX, factory barrel)... thanks for the input.

Send it. Then readjust the die next time. Bump comes up quick on the die... meaning, a small adjustment on the die can have a big change. Back it out a half turn and see what happens next time. Lock rings are pretty cheap, grab one with the little screw that clamps it down. Like the Lee ones. I use them a ton. The standard friction type are almost useless to me and my ham-fisted self. You can get one for each die you use a lot.

I bump .004 for my ARs. .002 for my bolt guns. But I've forgot to reset my die between and run .004 bumped cases in bolt guns. Never had anything bd happen.

To put it into perspective, we are talking less than the thickness of a dollar bill here. Can you see the difference on paper? Maybe... but the real question is, can you hold the difference? I'm pretty sure I can't

 

[BLKWLFK9]

On my dasher and with alpha dasher brass, .002 bump still has a tightish bolt close. .003-.004 closes much better and close to virgin brass feel.

 

[Tokay444]

On my dasher and with alpha dasher brass, .002 bump still has a tightish bolt close. .003-.004 closes much better and close to virgin brass feel.

With a .002 bump, are you sizing all the way down the side of the case past the extractor groove?
Not that a couple though is likely to make that difference I guess.
My Hornady full length die didn't size enough of the case to use brass shot in one chamber, on a different chamber. I had to switch to a Redding full length die to get the whole body sized. Different situation, completely, I know.

 

[Dthomas3523]

With a .002 bump, are you sizing all the way down the side of the case past the extractor groove?

Why/how would you size past the extractor groove?

 

[spife7980]

Why/how would you size past the extractor groove?

I think what he meant was "is the case getting sized at the base?" As in: are you sure that its the shoulder thats the hang up?

If not and he is asking about the rim then beats me too lol

 

[Ryridesmotox]

With a .002 bump, are you sizing all the way down the side of the case past the extractor groove?
Not that a couple though is likely to make that difference I guess.
My Hornady full length die didn't size enough of the case to use brass shot in one chamber, on a different chamber. I had to switch to a Redding full length die to get the whole body sized. Different situation, completely, I know.

You cant size that far and still get the case back out. The shell holder has to grip there.

 

[Tokay444]

Thank you Spife.
Sorry guys.

 

[Ryridesmotox]

Thank you Spife.
Sorry guys.

As someone who has stuck their fair share of cases. I can say, with authority, dont try it haha.

 

[Tokay444]

I can get there, and my Redding die does.

 

[Dthomas3523]

My first get down to the .20 line without issue on my co-ax.

 

[Punkur67]

Any thoughts on the Forster bushing neck bump die vs a FL die?

 

[Dthomas3523]

Any thoughts on the Forster bushing neck bump die vs a FL die?

As in neck sizing only??

 

[Punkur67]

As in neck sizing only??

This is the die info

 

[Dthomas3523]

This is the die info
View attachment 7275078

Looks like a FL bushing die. Most people use these over just a regular FL die, unless they get a die honed for their specific brass/bullet.

 

[pucker]

This is the die info

Looks like a FL bushing die. Most people use these over just a regular FL die, unless they get a die honed for their specific brass/bullet.

It bumps the shoulder and sizes the neck (bushing)...but does not size the body.

 

[spife7980]

And that’s what I don’t understand: how it does that without body support.

Unless it’s just touching tangentially along the sides and not actually pressing at all? But that’s a super fine line to ride and I don’t see how it could actually work properly in all but a few coincidental situations.

 

[Dthomas3523]

And that’s what I don’t understand: how it does that without body support.

Unless it’s just touching tangentially along the sides and not actually pressing at all? But that’s a super fine line to ride and I don’t see how it could actually work properly in all but a few coincidental situations.

I’d think this is intended for brass only to be fired out of the exact same chamber every time.

Theory would be less energy expanding case web = more energy pushing bullet.

I’d have to experiment with one to see if any extraction issues arise after a few firings.

 

[Dthomas3523]

Any thoughts on the Forster bushing neck bump die vs a FL die?

So, I have a basic understanding now.

Brass being sized this way will likely only function in the chamber it was fireformed in.

You’ll likely need to F/L size if using in another chamber.

 

[Dthomas3523]

I’d expect extraction issues over time though.

 

[Ryridesmotox]

With all the talk about how these champion long range F class guys use FL dies, I wonder why people still push neck only sizing or whatever other means. I've tried neck only with my lee collet, meh, it give go ok results for a bit then you have a hard time extracting or chambering after 5 firings and you start over, and your group isn't the same.

the Fclass shooter have to stack rounds at a pretty long range. If they FL size, I'll stick with that. Guarantee they've tried every widget out there for every part of brass prep, and they've come back to FL bushing dies or custom honed FL dies.

Hell, I get half-3/4 MOA out of my factory howa 308 using a cheap Lee FL die. It's not rocket surgery.

 

[Dthomas3523]

With all the talk about how these champion long range F class guys use FL dies, I wonder why people still push neck only sizing or whatever other means. I've tried neck only with my lee collet, meh, it give go ok results for a bit then you have a hard time extracting or chambering after 5 firings and you start over, and your group isn't the same.

the Fclass shooter have to stack rounds at a pretty long range. If they FL size, I'll stick with that. Guarantee they've tried every widget out there for every part of brass prep, and they've come back to FL bushing dies or custom honed FL dies.

Hell, I get half-3/4 MOA out of my factory howa 308 using a cheap Lee FL die. It's not rocket surgery.

Yep. Only time I see neck collet dies being using successfully long term is when they combine it with FL die without the bushing. Basically they are doing FL sizing and just using two steps instead of one. And they get very good results.

Neck sizing only will always produce issues after a while.

I’d expect issues over time with a neck/bump die as well.

 

[Ryridesmotox]

Yep. Only time I see neck collet dies being using successfully long term is when they combine it with FL die without the bushing. Basically they are doing FL sizing and just using two steps instead of one. And they get very good results.

Neck sizing only will always produce issues after a while.

I’d expect issues over time with a neck/bump die as well.

I've been considering a 2 step process, but I'm getting half-ish moa out of a factory howa with a normal, non bushing, not honed FL Lee die. I'm disinclined to give a crap about a level of consistency that I can't hold the difference of anyways. I think my next step will be to get a Forster die. But just a standard one. I already use the Forster Micro-seater. Not sure how much it really helped, but I do like its adjustment.

 

[Tokay444]

I use a Redding Comp bushing neck die, a Redding body die, and a 21st Century mandrel expander. I measure +/-.012mm runout at most.

 

[Steel head]

On my dasher and with alpha dasher brass, .002 bump still has a tightish bolt close. .003-.004 closes much better and close to virgin brass feel.

My 7 saum is similar.
It likes 2-3 more than 1-2 that my 260 easily deals with.

I’d expect extraction issues over time though.

I would as well.
I neck size a lot and I find when the cases get tight it’s as much or more the body than the shoulder causing it.

 

[_Raining]

I’d think this is intended for brass only to be fired out of the exact same chamber every time.

Theory would be less energy expanding case web = more energy pushing bullet.

I’d have to experiment with one to see if any extraction issues arise after a few firings.

I feel like for this to work properly, you would need the die to be cut specifically to match your chamber. Otherwise, the die could size the brass if the die is too small or if the die is too large it might allow the case to bulge out under the pressure of resizing the neck and shoulder. But I have 0 knowledge about material science so idk what the likelyhood is of the brass bulging out when unsupported in the die.

 

[Dthomas3523]

I feel like for this to work properly, you would need the die to be cut specifically to match your chamber. Otherwise, the die could size the brass if the die is too small or if the die is too large it might allow the case to bulge out under the pressure of resizing the neck and shoulder. But I have 0 knowledge about material science so idk what the likelyhood is of the brass bulging out when unsupported in the die.

I see no benefit to not F/L sizing. So I’d never mess with it.

 

[Steel head]

I see no benefit to not F/L sizing. So I’d never mess with it.

As I see it the only reasons to neck size or neck/bump size is to satisfy the lazy reloaders like me.

 

[Dthomas3523]

As I see it the only reasons to neck size or neck/bump size is to satisfy the lazy reloaders like me.

Yea, that’s the only valid reason. Time saving if you are ok with one day having tight bolt and such.

The better accuracy and what not is bullshit.