bumping the shoulder .001?

[LHSmith]

For the average reloader who is not into competition, I suggest 0.002" bump for bolt actions will suffice their needs. As mentioned cases that are from with-in the same lot, sorted, shot the same number of times with the same loads in the same chamber, and sized with the same lube MAY not always yield the same dimension after sizing......just be aware of this trait for brass to vary in springback so as to not get discouraged with your measuring ability.

 

[MrMajestic]

I use Larry Williams digital Headspace gage.
http://larrywillis.com/
Also proper annealing every cycle will help with consistency.

 

[Marksman63]

I use a RCBS precision micrometer. Easy and accurate

 

[918v]

First of all, you can't bump the shoulders efficiently and reliably in .001" increments. There is too much variance in press springing and brass hardness.

To eliminate the variance induced by the press, use Redding competition shell holders which have different deck heights in .002" increments. You can cam over these and remove any linkage slop and press frame springing variance. Then you will only have brass hardness to deal with.

 

[LHSmith]

^^^^^^ Poppycock-with the proper tools you can bump to 0.0005". Again, this degree of precision is not necessary for 95% of reloaders......but it IS possible.

 

[JRS]

First of all, you can't bump the shoulders efficiently and reliably in .001" increments. There is too much variance in press springing and brass hardness.

To eliminate the variance induced by the press, use Redding competition shell holders which have different deck heights in .002" increments. You can cam over these and remove any linkage slop and press frame springing variance. Then you will only have brass hardness to deal with.

Actually - you can. The JLC insert is adjustable in increments of .00075. If one is using an O type press, there is no worry about "springing" the press, unless it is made from something other than cast iron, or, is a C type press.

 

[rayjay]

^^^^^^ Poppycock-with the proper tools you can bump to 0.0005". Again, this degree of precision is not necessary for 95% of reloaders......but it IS possible.

Exactly... That pic with the RCBS caliper and the Harrells bush is my pic. That's one of my 30BR cases. They measure X.071 after firing and x.0695 after sizing. Annealed every 3 firings. People that say they can't bump shoulders this precisely need to anneal their brass. They probably also struggle with stiff seating.

 

[918v]

^^^^^^ Poppycock-with the proper tools you can bump to 0.0005". Again, this degree of precision is not necessary for 95% of reloaders......but it IS possible.

I never said it was impossible. I said it was inefficient and a waste of time.

 

[Bob L.]

I use Larry Williams digital Headspace gage.
http://larrywillis.com/
Also proper annealing every cycle will help with consistency.
[/quote

Both these have helped me considerably. Also holding the case in the die for a 5 count.

 

[ridgeway]

First of all, you can't bump the shoulders efficiently and reliably in .001" increments. There is too much variance in press springing and brass hardness.

Really? I've been bumping shoulders and holding .0005" and better for years, LOL

 

[tenring]

I love my Redding Instant Indictor for measuring bump.

 

[chkunz]

First of all, you can't bump the shoulders efficiently and reliably in .001" increments. There is too much variance in press springing and brass hardness.

To eliminate the variance induced by the press, use Redding competition shell holders which have different deck heights in .002" increments. You can cam over these and remove any linkage slop and press frame springing variance. Then you will only have brass hardness to deal with.

My experience also.

 

[918v]

First of all, you can't bump the shoulders efficiently and reliably in .001" increments. There is too much variance in press springing and brass hardness.

Really? I've been bumping shoulders and holding .0005" and better for years, LOL

What's laughable is people dwelling on .0005" shoulder bump when using RCBS or Redding standard FL dies that grossly overwork the neck. Talk about stiff seating.

 

[LHSmith]

What's laughable is people dwelling on .0005" shoulder bump when using RCBS or Redding standard FL dies that grossly overwork the neck. Talk about stiff seating.

We are talking about those who NEED (usually for competitive reasons) to produce ammo to close tolerances, most of which are driving custom actions and reload with custom dies - or- have a chamber cut to closely match an off-the-shelf die. No one inferred maintaining half a thou bump would benefit everyone. Since this is ACCURATE Shooter.com many ask what factors in reloading affect accuracy........well shoulder bump is one of them......and it's been proven in the competitive arena.

 

[ridgeway]

First of all, you can't bump the shoulders efficiently and reliably in .001" increments. There is too much variance in press springing and brass hardness.

Really? I've been bumping shoulders and holding .0005" and better for years, LOL

What's laughable is people dwelling on .0005" shoulder bump when using RCBS or Redding standard FL dies that grossly overwork the neck. Talk about stiff seating.

That .0005" can be the difference between a smooth effortless bolt close to one that has a bit of resistance that upsets the bags.

 

[savagedasher]

My dies and my set up would me do .00005 but my brass doesn't agree. Larry

 

[Macropod]

There are various ways of measuring cartridge base to shoulder length but the worst part is the die set up.

I made this gadget from a left over section of barrel partially chambered using the same reamer as my comp rifle. Excellent for shoulder bump and also serves as datum for bullet jam, throat wear etc.

 

[boltfluter]

My dies and my set up would me do .00005 but my brass doesn't agree. Larry

What?

Paul

www.boltfluting.com

 

[fourpower]

get the tool from larry willis and never look back. it works for everything and all calibers.

 

[Warren Dean]

I love my Redding Instant Indictor for measuring bump.

+1 The easiest tool to use. I use mine all the time.