Shoulder set back questions

[AWLEAPHART]

Shoulder bump questions.
1: All rifle shoulders should be bumped back 0.02" for hunting?
2: What does it mean when some case shoulders bump back more or less than the rest of your cases. Example 0.03" or 0.01" do you trash them or still use them.
3: How do you know what is a GOOD inside diameter to use for measuring your shoulder set back? Example I think inside diameter used for my .284 Win. Is .411
4: If you have a tight bolt close feeling coming from shoulder needing to be set back- in what way does it affect accuracy?
5: when setting shoulder back does it set the whole peace back between neck and body or just at the body and shoulder meeting spot?
Anthony

 

[bglenn]

1: All rifle shoulders should be bumped back 0.02" for hunting?
shoulders should be bumped back .002 for hunting

2: What does it mean when some case shoulders bump back more or less than the rest of your cases. Example 0.03" or 0.01" do you trash them or still use them.
It could be that the shoulder and neck need annealed.

3: How do you know what is a GOOD inside diameter to use for measuring your shoulder set back? Example I think inside diameter used for my .284 Win. Is .411
You measure the outside of the tapered part of the shoulder - a length from the head to the tapered shoulder.

4: If you have a tight bolt close feeling coming from shoulder needing to be set back- in what way does it affect accuracy?
It can cause the bolt lugs to Gould not good for the rifle. I can't tell it matters on accuracy. If you have a spring loaded ejector it can fool you for feel.

5: when setting shoulder back does it set the whole peace back between neck and body or just at the body and shoulder meeting spot?
All of the taper.

Glenn

 

[Larryh128]

+1 on Glenn, #2 does need to be annealed. #3 , I made or have someone turn you a piece of 1/2-3/4" round stock about 1/2" long. Square both ends.
Bore the piece to the datum line diameter for the round 1/4" deep (half way down the shoulder diameter) & the rest a couple thousands larger than the fired OD of the neck. When this is placed on the fired case & measured with calipers, you will have a reading & all that is necessary is to adjust the dies until you're reading .002 less than the 1st reading. Note that before you start bumping the shoulder back, you will actually stretch it longer from the expander ball being drawn thru several times. Keep checking & you will get it perfect. #4 won't change accuracy but it's a pain.

 

[Catfish]

What Glen said is true, but I think your makeing it all to complicated. If your haveing no trouble closeing the bolt there is no need to set the shoulder back more. If your shooting hot loads you will need to set the shoulder back alot more often. If you shooting liter loads you may never have to set back the shoulders.

 

[flatlander]

Belted or not, the best way to determine the need for shoulder bump is still a headspace gauge like Stoney Point (now Hornady) attached to a dial or digital caliper.

It's also common for a FL die to move the shoulder forward when you've got it set several thousandths from even touching the shoulder - most common when you've got a fairly tight-bodied die in combination with a somewhat loose-bodied chamber.

 

[PREMOD70]

I'll throw a word in for RCBS precision micrometers, a very good instrument for setting up a sizing die as well as other reloading measurements.

 

[Innovative]

I'll throw in a word for the Digital Headspace Gauge, because unlike the RCBS Precision Mic - it works on ALL calibers. It's very simple to use, and it also measures bullet jump to the rifling without needing special attachments or bushings.

Setting the shoulder back - .001" to - .002" will eliminate the chance of case head separations. It also reduces case run-out.

 

[bozo699]

I'll throw in a word for the Digital Headspace Gauge, because unlike the RCBS Precision Mic - it works on ALL calibers. It's very simple to use, and it also measures bullet jump to the rifling without needing special attachments or bushings.

Setting the shoulder back - .001" to - .002" will eliminate the chance of case head separations. It also reduces case run-out.

A big + 1 for me also I wouldn't want to go back to the stoney point or Hornaday or any other head space tools after I used Larry Willis's Headspace gauge I wouldn't be with out it now. I don't use the tool for bullet jump but I have used it for sorting bullets by putting a seating stem in the mouth of the tool, works great! Best $90 I have spent on reloading equipment.
Wayne.

http://larrywillis.com/

 

[jr600yd]

+1 for Bozo699. One of the best investments you can make in reloading tools.

 

[dreever]

Been using the Innovative Digital headspace Guage for a couple of years now. I give it a two thumbs up!

Danny

 

[Zia Hunter]

After reading your comments on the Innovative Designs tool, I went ahead and ordered one. Thanks.

 

[bozo699]

I guarantee you won't be disappointed the tool is very self explanitory but if you have any problems, ask away and if you don't get what your looking for on here Larry is great about explaining things, I have communicated to him by email and telephone and is a down to earth guy.
Wayne.